explain xkcd - User contributions [en]

3049: Incoming Asteroid

2025-02-11T12:01:33Z

Sabik: /* List of sizes and consequences */ add injuries for Chelyabinsk meteor

{{comic
| number = 3049
| date = February 10, 2025
| title = Incoming Asteroid
| image = incoming_asteroid_2x.png
| imagesize = 454x570px
| noexpand = true
| titletext = The bottom ones are also potentially bad news for any other planets in our solar system that have been counting on Earth having a stable orbit.
}}

==Explanation==
{{incomplete|Created by an incoming bearer of bad news - More accurate readings of the log scale, and provide detailed explanations of each point on the chart (should probably be a table, as well). Do NOT delete this tag too soon.}}

This comic may be inspired by the recent discovery of asteroid {{w|2024 YR4|2024 YR4}}, which is estimated to have about a 2% chance of striking Earth on December 22, 2032. Its size is estimated to be 40-90 meters.

This comic provides a log scale correlating the size of any incoming asteroid to whether its arrival is good or bad news. While asteroids on the smaller end of the scale are good news for sky watchers, as the upcoming objects get bigger, the potential for catastrophe grows. Many astronomy enthusiasts would be happy to see bigger meteors, as bigger generally means more exciting pictures. Of course, once the meteors grow past a certain size even the most enthusiast astronomer might grow concerned about their imminent extinction.{{cn}}

===List of sizes and consequences===
Sizes are approximate.

* '''1 cm''': Good news! Meteors are pretty!
** Nothing more than a streak in the sky.

* '''30 cm''': Great news! You might see a fireball!
** Might descend far enough for the flames of its entry to be visible with the naked eye.

* '''3 m''': Okay news, unless you have expensive windows or are very unlucky.
** Can descend far enough for the shockwave of its passing to shatter windows. The comic mockingly claims this is only a problem if your windows are expensive or happen to get directly hit by it. The {{w|Chelyabinsk meteorite}}, sitting near the upper bound of this category with approximately 18 m in size, damaged more than 7,000 buildings with shockwaves, injuring almost 1500 people.

* '''100 m''': Bad news, especially if you live near the city it's aimed at.
** The {{w|Tunguska event|Tunguska meteor}}, which flattened over 2,000 km2 of Siberian forest in 1908, was 50-60 m across.

* '''1 km''': Bad news, especially if you live on the continent it's aimed at.
** Can easily cause localized extinction, and can be expected to have effects on the rest of the world as well.

* '''6 km''': Bad news for your species.
** The {{w|Chicxulub crater|Chicxulub asteroid}} that wiped out non-avian dinosaurs was about 10 km in diameter.

* '''50 km''': Bad news for your phylum.
**{{w|Chordate|Our phylum}} is primarily all the vertebrate animals.

* '''200 km''': Bad news for your biosphere.
** A global extinction event is pretty much guaranteed.

* '''3,000 km''': Good news for any life that might some day evolve on Earth's new moon.
** Earth's moon is believed to have been formed when Earth, in its infancy, was hit by an object of roughly this size. The comic assumes that another moon would form from another such impact, hypothesizes that life might evolve on that moon, {{tvtropes|BadNewsInAGoodWay|and pretends that it's good news}}.

* '''30,000 km''': Bad news for whatever planet is about to get hit by Earth.
** At this size, the "asteroid" is over twice as large as Earth itself (whose diameter is about 12,700 km) and would likely be classified as a planet. (Unofficially, at least. ''Officially,'' there would be quibbling about whether it had "cleared its orbit." Briefly. {{Citation needed}}) At that point, the comic points out, it would be more accurate to describe the Earth crashing into the "asteroid"/planet, not the other way around.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Header:]
:An asteroid is headed straight for Earth! That's...

:[A log scale of lengths is shown, labelled "Asteroid size", with markings of 1 cm, 10 cm, 1 meter, 10 meters, 100 meters, 1 km, 10 km, 100 km, 1,000 km, and 10,000 km. The remaining lines of text are at various points down the scale.]
:...Good news! Meteors are pretty!

:...Great news! You might see a fireball!

:...Ok news, unless you have expensive windows or are very unlucky.

:...Bad news, especially if you live near the city it's aimed at.

:...Bad news, especially if you live on the continent it's aimed at.

:...Bad news for your species.

:...Bad news for your phylum.

:...Bad news for your biosphere.

:...Good news for any life that might someday evolve on Earth's new moon.

:...Bad news for whatever planet is about to get hit by Earth.

{{comic discussion}}

[[Category:Charts]]
[[Category:Astronomy]]
[[Category:Space]]

Talk:2922: Pub Trivia

2024-04-22T04:29:33Z

Sabik: Who played the drums? Keith Moon

I expect that the BTS question is a reference to the traditional Korean system of counting a person's age in units of Sal which started at 1 and incremented on the first day of the year. Since this system was abandoned on official documents in 2023, but is still in use in some contexts, the question of whether every member of BTS had a "birthday" on the first day of the year is ambiguous. [[User:Philhower|Philhower]] ([[User talk:Philhower|talk]]) 14:13, 19 April 2024 (UTC)

question 5, planets exist outside the solar system, adding to the ambiguity. [[User:Philhower|Philhower]] ([[User talk:Philhower|talk]]) 14:15, 19 April 2024 (UTC)
:One of the requirements in the definition of a planet is that it orbits the Sun, so no there are no planets outside the Solar system. [[User:Tharkon|Tharkon]] ([[User talk:Tharkon|talk]]) 17:50, 19 April 2024 (UTC)

::{{w|NASA}} disagrees. [https://exoplanetarchive.ipac.caltech.edu/ Exoplanet Archive] shows 5612 confirmed planets. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 20:55, 19 April 2024 (UTC)
::: The IAU is the body that defines such things - and they do say that planets have to orbit the Sun...things that orbit other stars are properly called "exo-planets". But still - do we include dwarf planets? Rogue planets? It's definitely a crazy-vague question. [[Special:Contributions/172.70.211.219|172.70.211.219]] 21:05, 19 April 2024 (UTC)
:::: the IAU is one body that claims the authority to define such things, but their authority is not recognized by any of the things they are claiming the right to name. (Except for a very small part of earth, mostly made of humans) [[Special:Contributions/172.69.58.203|172.69.58.203]] 00:10, 20 April 2024 (UTC)
::::That seems ridiculous, "If it isn't one of ours it don't count"? That'd be like saying "They're only 'cars' if they use North American roads, in other countries using THEIR roads you have to call them exo-cars!". LOL! And every future/space-based fiction calls them planets, just makes more sense not to be so arbitrarily exclusionary. Ours isn't the only sun, we shouldn't pretend it has some aspect that makes it count more than others - outside of that it's the one with us. [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 06:09, 20 April 2024 (UTC)
::::: Correction, the IAU definition explicitly states that it is only about planets within the solar system and has no comment about exoplanets one way or the other. Presumably, to leave some flexibility on all the weird edge cases that are bound to come up with exoplanets. https://www.iau.org/static/resolutions/Resolution_GA26-5-6.pdf [[Special:Contributions/172.68.195.213|172.68.195.213]] 07:55, 21 April 2024 (UTC)

: I think the correct answer is 0: before the solar system formed there were no planets. So, originally, there would have been none. If exo-planets count, going back to the beginning of time gives the same answer: when the universe came into existence during the big bang there were no stars, let alone planets orbiting them. Even religion agrees: in the beginning God created the earth and the heavens, but the sun came later, so technically earth was not a planet since it didn't orbit anything.--[[Special:Contributions/162.158.62.49|162.158.62.49]] 22:23, 19 April 2024 (UTC)

As for question 9, please see the note about the history of Austrailia's capitals at: [[https://en.wikipedia.org/wiki/List_of_former_national_capitals#Oceania]]. and the page regarding countries with multiple capitals [[https://en.wikipedia.org/wiki/List_of_countries_with_multiple_capitals]] [[User:Philhower|Philhower]] ([[User talk:Philhower|talk]]) 14:24, 19 April 2024 (UTC)
: See Also [https://en.wikipedia.org/wiki/List_of_Australian_capital_cities List of Australian capital cities] - As an Australian, I believe many would also consider the major city in their state/territory to be a capital city, although not the capital of Australia.

About the alt text, London is certainly in Europe. The question itself is malformed because "Europe (or 'the EU')" is not self-consistent: there is a lot of European countries that are not part of the EU. [[User:RedGolpe|RedGolpe]] ([[User talk:RedGolpe|talk]]) 14:32, 19 April 2024 (UTC)
:The "Greater London" answer is also tricksy, as the "ceremonial county" of GL {{w|London boroughs|may not include}} the additional area of the City Of London (though it does include the City Of Westminster, which is sometimes the trick answer to certain trick questions that a quizmaster might attempt to pull). The ''administrative'' Greater London is the ceremonial one ''plus'' CoL, however... [[Special:Contributions/172.70.162.19|172.70.162.19]] 15:04, 19 April 2024 (UTC)
::I would argue London is not in Europe because there is no clear definition for Europe as a geographic area, it really doesn't have an eastern border that is not arbitrary, so the only clearly defined thing Europe can refer to is the EU. [[User:Tharkon|Tharkon]] ([[User talk:Tharkon|talk]]) 17:50, 19 April 2024 (UTC)
:::London, France is both in Europe and the EU https://en.wikipedia.org/wiki/London,_France [[Special:Contributions/172.70.163.49|172.70.163.49]] 18:00, 19 April 2024 (UTC)
:::While the eastern border of Europe is not clearly defined I am not aware that there is any definition of (geographic) Europe that excludes the islands (and subsequently London) --[[Special:Contributions/162.158.202.135|162.158.202.135]] 21:24, 19 April 2024 (UTC)
::::There's "mainland Europe", excluding islands. Or at least any of several possibly island archipeligos and/or island nationstates. e.g. Mont-Saint-Michel might not be (exluded, that is, due to being French and having a (tide-dependant) ground access), Jersey would be (British Crown Territory island), Malta probably (island state), Sicily would depend on your thinking (it being Italian, and much larger than the strait that makes it an island offshoot). Most of Scandinavia might be interestingly included (with Denmark) or excluded (with Iceland), according to context. Even Gibraltar might or might not be, depending upon upon the thinking (or lack of it) behind the use of the term. (But, fiddling around the edges aside, (the English) London is not in "mainland Europe" and hasn't been for maybe a full 10kY before it became "London" in any useful sense.) [[Special:Contributions/172.70.163.49|172.70.163.49]] 23:44, 19 April 2024 (UTC)

::::: The phrase "continental Europe" is also used, and might be implied by a British person saying "I travelled around Europe last year". [[Special:Contributions/172.69.195.54|172.69.195.54]] 15:01, 21 April 2024 (UTC)

::::: The (semi-)apocryphal headline "Fog In Channel, Continent Cut Off" is perhaps indicative of the {{w|Continental Europe#Great Britain and Ireland}} British collective mindset (of which I must therefore be a component, albeit not at that end of the spectrum). [[Special:Contributions/172.71.242.71|172.71.242.71]] 15:39, 21 April 2024 (UTC)

The [https://en.wikipedia.org/wiki/Benxi Benxi Lake] is actually considered to be the smallest lake in the world. [[Special:Contributions/172.70.135.205|172.70.135.205]]
:{{cn}}[[Special:Contributions/172.70.86.176|172.70.86.176]] 14:40, 19 April 2024 (UTC)

I never realized how challenging it is to edit pages when they've just been posted. Makes me long for something like Google docs.[[Special:Contributions/172.68.3.43|172.68.3.43]] 14:39, 19 April 2024 (UTC)

People, who are born on 29th February don't have a birthday in years which are not leap years. However, 2024, when this comic was published is a leap year. --[[Special:Contributions/162.158.95.9|162.158.95.9]] 14:40, 19 April 2024 (UTC)

"5. How many planets were there originally?" This could also refer even back to the start of the universe, when there were (likely) just 0 planets. --[[Special:Contributions/162.158.86.101|162.158.86.101]] 14:43, 19 April 2024 (UTC)

I anticiated a lot of Edit Conflicts, but not actually quite so many as to not to be able to resolve my edits with everyone else's. This is the bare-bones that I was putting in (until finding multiple attempts tried to be added consecutively...
{{cot}}
{| class="wikitable"
|-
! Question !! Problem !! Possible answer(s)
|-
| Which member of BTS has a birthday this year?
| Every living person has a birthday this year (being a leap-year, this includes those born on 29/Feb).
|
|-
| How many sides does a platonic solid have?
| There are five (or [[2781: The Six Platonic Solids|six]]) platonic solids, each with a different number of sides.
| 4, 6, 8, 12 or 20
|-
| What is the smallest lake in the world?
| The distinction between a small lake and a pond, pool or puddle (for example) is difficult to define.
|
|-
| Which Steven Spielberg movie features more shark attacks? Jaws (1875) or Lincoln (2012)
| Not a problem, as Lincoln has very few shark attacks.{{Citation needed}} The problem is that barely anyone will ''not'' be able to correctly answer this.
|
|-
| How many planets were there originally?
| Contextually vague. At what time and within what volume of space, and what is the scope of 'planet' defined here?
|
|-
| What NFL player has scored the most points outside of a game?
| Outside of (NFL) games, individuals may accumulate points in any number of ways (e.g. Scrabble)
|
|-
| The Wright brothers built the first airplane. Who built the last one?
| Until no further planes are built, individuals/teams/companies continue to build (to completion) ever more examples, changing the answer possibly moment to moment.
|
|-
| Is every even number greater than 2 the sum of two primes?
| This is a {{w|Goldbach's conjecture|currently unanswered question}}.
|
|-
| Not counting Canberra, what city is the capital of Australia?
| Canberra is ''the'' capital of Australia, a fairly well known 'obscure' fact. Each Australian territory also has their own state capital, so there is not one other ''single'' example.
|
|-
| Who played the drums?
| Lack of context. With which group? For which song? For which (re-)recording? At which event?
|
|-
| Where is London located? (a) The British Isles (b) Great Britain and Northern Ireland (c) The UK (d) Europe (or 'the EU') (e) Greater London
| Almost all of these are correct (though London is geographically in Europe but no longer in the EU).
|}

This is apparently deliberate (at least on behalf of the organisers), perhaps to upset or otherwise impede groups of overconfident quizzers who would otherwise dominate any genuinely good quiz.
{{cob}}
...make use of it however you wish, anybody who has the time not to keep chasing all the simultaneous edits. (The above is a bit behind 'perfection', and lacks many of the integrations, wikilinks and adjustments I had made. I backspaced out of the edit I had finally reached, before remembering to take a full copy into my paste-buffer!) [[Special:Contributions/172.70.90.115|172.70.90.115]] 14:53, 19 April 2024 (UTC)

I thought the answer to #2 could be 1, because as 3D solids they only have one surface. I would guess the player with the most points outside of a game is the one who's played idlers (like Cookie Clicker) the longest — though I suppose those could be considered "inside of a game" as well. Also, I played the drums. [[Special:Contributions/172.70.254.143|172.70.254.143]] 15:33, 19 April 2024 (UTC)
:The answer to #2 is '2 - the in-side and the out-side'.[[Special:Contributions/172.69.43.242|172.69.43.242]] 15:46, 19 April 2024 (UTC)

Considering the platonic solids explanation lists all the correct answers, could someone include a list of all the members of BTS and their respective birthdays? Bing copilot suggests the following:

1. **Jin (Kim Seok-jin)**:
- Birthday: **December 4, 1992**

2. **Suga (Min Yoon-gi)**:
- Birthday: **March 9, 1993**

3. **J-Hope (Jung Hoseok)**:
- Birthday: **February 18, 1994**

4. **RM (Kim Nam-joon)**:
- Birthday: **September 12, 1994**

5. **Jimin (Park Ji-min)**:
- Birthday: **October 13, 1995**

6. **V (Kim Tae-Hyung)**:
- V's birthday is **December 30**, but the year is not mentioned in the provided information.

7. **Jungkook (Jeon Jungkook)**:
- Jungkook's birthday is **September 1**, but the year is not mentioned in the provided information.
[[Special:Contributions/172.70.162.19|172.70.162.19]] 15:48, 19 April 2024 (UTC)

: I'm not opposed to adding BTS birthdays, but I think it should be done by someone more knowledgeable about the band than me. Birthdays can be a surprisingly nuanced subject.[[User:Comatoran|Comatoran]] ([[User talk:Comatoran|talk]]) 15:59, 19 April 2024 (UTC)
:Wikipedia says {{w|V_(singer)|'95}} and {{w|Jungkook|'97}} respectively[[Special:Contributions/172.70.162.37|172.70.162.37]] 16:04, 19 April 2024 (UTC)

London is both a City (London) and a City within a City (The City of London) and an Area (Greater London)
There are also many more places named London than the one that is the Capital of the UK .. Serbia, France, Canada (Which is larger and the one in the UK), 10 in the USA, and one on Kiribati 17:56, 19 April 2024 (UTC)
:Are you saying London, Ontario, Canada is BIGGER than the more famous London, England??? That's a country capital! Is that seriously true? I'm Canadian, I don't know London, ON as being THAT big... [[User:NiceGuy1|NiceGuy1]] ([[7User talk:NiceGuy1|talk]]) 05:52, 20 April 2024 (UTC)
::It's very unlikely to be larger in population terms than the (common!) wider definition of the main UK London, as that would make it larger than any other city in Canada by a large margin. In terms of area, London ON is very likely to be larger than the City of London (which is surprisingly small). More widely, the definition of what actually is a "city" is more complex than it appears to be at first glance; administrative areas (what official statistics are collected for) are often quite different from where the bulk of people are. --[[Special:Contributions/162.158.74.25|162.158.74.25]] 07:20, 20 April 2024 (UTC)
:::Some wikipedia figures, for reference:
:::*{{w|London, Ontario}} = 168.76 sq mi, Population 422,324
:::*{{w|City of London}}, subset of Capital of UK = 1.12 sq mi, Population 8,618
:::*{{w|London}}, administrative/etc capital of UK = 606.96 sq mi, Population 8,799,800
:::*{{w|London, Belgrade}} = a 'neighbourhood' (<1 sq mi?), Population unknown
:::*{{w|London, France}} = 'a small agricultural village'
:::*...
:::*{{w|List of minor planets: 8001–9000#837|8837 London}} = 1.5 mi diameter (~28s q mi, ~14 cu mi?), Population... some of the {{w|Clangers}}?
:::I skipped a few of the others (e.g. the various US ones: cities, townships, communities)... [[Special:Contributions/162.158.230.46|162.158.230.46]] 18:10, 20 April 2024 (UTC)

I'm surprised there were no phishing-type questions (i.e. "what are the last four digits of your social security number", "what are the three numbers on the back of your debit card", etc).22:33, 19 April 2024 (UTC)

The only correct answer(s) to "who played the drums" would be "the drummer", or "twelve drummers", but I would accept Phil Collins, Alex Van Halen, or Ringo Starr for half a point each [[Special:Contributions/108.162.241.100|108.162.241.100]] 02:40, 20 April 2024 (UTC)
: "Who played the drums" is Keith Moon; in this cryptic clue, "Who" is the name of the band, and "played the drums" indicates the drummer; hence the answer is Keith Moon, the drummer of The Who. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 04:29, 22 April 2024 (UTC)

I asked my Mom these questions & she said the answer to #7 so flatly: ''Boeing ''
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 02:44, 20 April 2024 (UTC)

On the Capital of Australia: Melbourne hosted parliament before Canberra was built, and Jervis Bay was part of the ACT: https://en.wikipedia.org/wiki/Jervis_Bay_Territory

Are there people outside of the USA that are surprised to learn that Washington D.C. is the capital of the USA, rather than New York, Los Angeles, Chicago etc. due to its relatively small population? ("only" ~670000 in 2024) [[User:These Are Not The Comments You Are Looking For|These Are Not The Comments You Are Looking For]] ([[User talk:These Are Not The Comments You Are Looking For|talk]]) 06:50, 21 April 2024 (UTC)

I came here all prepared to say that the Title Text should have Ontario, Canada as a (likewise correct) answer, but I see somebody already put that into the table, LOL! I feel like the "More Reasonable" version of the planet question should NOT mention Pluto, it should be the question IMPLIED in the comic whose answer is 9 (such as "How many planets were originally in our Solar System", but without the ambiguity of "originally". Basically a question whose answer is 9, pushing people to include Pluto, while allowing people the mistake of saying the current answer of 8, but mentioning Pluto would ruin that/the question). [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 05:52, 20 April 2024 (UTC)

There could also be a person Named "London" who is located somewhere, perhaps in the same bar (or not) -- [[Special:Contributions/172.70.46.71|172.70.46.71]] 12:13, 20 April 2024 (UTC)
:https://en.wikipedia.org/wiki/London_%28name%29 [[Special:Contributions/172.70.42.31|172.70.42.31]] 16:27, 20 April 2024 (UTC)

I thought I knew the minimum size of a lake by definition, at least in the US, but I just found different authorities asserting 1, 10, and 20 acres as the distinction between a lake and a pond. Two non-metric distinctions are that a lake has an aphotic (dark) zone, or a lake is fed and drained by a river, but they don't help here. [[Special:Contributions/172.70.43.53|172.70.43.53]] 16:22, 20 April 2024 (UTC)

For the love of god can we stop saying that Pluto was "demoted" to a dwarf planet? It didn't have its category changed, it had its category defined (for the first time!). It was a founding member of a newly named category. And it's not like planets are better than dwarf planets, they're just different. (I'm going to die on this hill, ain't I?)
[[Special:Contributions/172.68.34.16|172.68.34.16]] 01:35, 21 April 2024 (UTC)
:Yes, you probably are. When it happened, many people, including astronomers, considered it a downgrade. There's some prestige in being a planet -- the Sun and the planets are considered the most significant objects in the Solar System. The qualifier suggests that it's less important than the "real" planets, and was kicked out of the planet club for being deficient in some way. Maybe we need a campaign from dwarf humans to remind everyone that they're just smaller, but they have no less dignity. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 23:41, 21 April 2024 (UTC)

For the planet question there's also Theia, which is theorized to have been a planet prior to smashing into proto Earth and forming the moon and modern larger Earth. So there used to be at least nine planets by the current definition in our solar system.
[[Special:Contributions/162.158.155.20|162.158.155.20]] 03:50, 21 April 2024 (UTC)

For question #8, it's not that mathematicians were idling around. A lot of partial results were made, see Wiki. [[Special:Contributions/172.71.160.33|172.71.160.33]] 08:22, 21 April 2024 (UTC)

I was confused by this question at first. The answer is "no." It is disproved by example. 21+3=24 21 is not a prime. 24 is even. {{unsigned ip|162.158.154.65|19:38, 21 April 2024
:24 is the sum of many pairs of numbers. Amongst those pairs (as with any even number >2) may be one ore more pairs of primes (even 2, if you count 1 as a prime - though generally one doesn't). 24 is (just looking at the odd numbers >1) 21+3, 19+5 (both primes!), 17+7 (both primes), 15+9 (no), 13+11 (both primes) and then of course the reverses of these (if you count those). So 24 is the sum of two primes (three, or six, times). 4 is just the sum of 2+2, 6 is only 3+3, 8 is only 5+3... And every even number checked from there on up ''can'' be expressed as the sum of two primes (at least once). But is there ever a point at which there is an even number that is not?
:With 3, 5 and 7 being primes, then you can definitely say that if N is an even number that has (or even relies upon) a solution with 3, then N+2 and N+4 are, which would be answerable by the same sum but with 5 or 7 instead. Plus N+8 (3->11), N+10 (3>13). And maybe you can fill in the N+6 and N+8 by the ''other'' prime used being also a suitable twin prime that you can swap out for the P±2 partner. But only if it's the right prime of any given pair, and not all primes are twins, so there's a lot more to consider about whether any given advancement up the even-numnber ladder can be answered by a suitable pair of primes.
: e.g. 15440=7717+7723 (one possible solution). 15442 therefore needs +2 to that. But 7717 and 7723 ar adjacent primes that areen't two apart (so you can't just add two to 7717 and have 7723 + 7723) and the next adjacent primes are 7703 and 7727 (not two apart, and not obviously useful to go 7717->7703, either). So there must be another solution (theoretically, but also proven by having been checked). By doing ''quite a bit'' of to-and-fro (if that's how we're doing it), we can finally announce that 15442=7649+7793 (but I also found 7523+7919, 7541+7901, 7559+7883 and 7589+7853, before I stopped the search). So It works up to 15442.
:15444? Well, neither 7649 or 7793 have a +2 prime-partner. But 7589 is followed by 7591 (as a new partner to 7853). And 7559 is followed by 7561, so 7561+7883 would also be an answer. There will (probably) be many others.
:But will there ''always'' be many others? Or even just the one? I'm sure someone has been counting how many unique (bidirectional) solutions each number has, and probably there are some that ''only just'' get the requisite single pair of primes that sum to it. Could it ever not even manage that? Those actually familiar with the efforts to prove the conjecture would know, rather than a fool like me coming fresh to the problem. (Relatively, that is... I already knew about it, but I've never tried to wade into the actual theory until right now, and this random example I set up to 'explain' this, just now.) [[Special:Contributions/172.71.242.175|172.71.242.175]] 21:01, 21 April 2024 (UTC)

1897: Self Driving

2023-01-25T06:42:58Z

Sabik: /* Transcript */ fix typo in transcript

{{comic
| number = 1897
| date = October 2, 2017
| title = Self Driving
| image = self_driving.png
| titletext = "Crowdsourced steering" doesn't sound quite as appealing as "self driving."
}}

==Explanation==
This comic references the approach of using {{w|CAPTCHA}} inputs to solve problems, particularly those involving image classification, which are not solvable by computers, specifically {{w|reCAPTCHA}} v2's fallback puzzle, and hCaptcha's puzzle, both of which are based on identifying road features and vehicles. A reCAPTCHA version of this puzzle would ask "check all squares containing a STOP SIGN" using one or more images derived from {{w|Google Street View}}.

Such an approach can serve to create the learning set as the basis for training an {{w|artificial intelligence}} (AI) to better recognize or respond to similar stimuli. This approach was used by Google, the owners of reCAPTCHA, to identify house numbers in Street View to improve their mapping, and nowadays Google also uses CAPTCHAs to identify vehicles, street signs and other objects in Street View pictures. This might be a reasonable way to help improve the performance of the AI in a self-driving car that responds to video input, by reviewing images it might encounter and flagging road signs, etc. that it should respond to. Later a similar approach to learning important things, for the robots, was used in [[2228: Machine Learning Captcha]].

However, the temptation might be to simply sidestep the hard problem of AI by having all instances 'solved' by "offloading [the] work onto random strangers" through CAPTCHAs. For example, this has been used to defeat CAPTCHAs themselves; people were asked to solve CAPTCHAs to unlock pornographic images in a computer game, while the solution for the CAPTCHA was relayed to a server belonging to cybercriminals. (See [http://news.bbc.co.uk/2/hi/technology/7067962.stm PC stripper helps spam to spread] and [https://doi.org/10.1016/S1353-4858(08)70036-9 Humans + porn = solved CAPTCHA]).

Alarmingly, the developers of this '{{w|Self-driving car|self driving}}' car seem to have gone for the lazy approach. Instead of teaching an AI, the CAPTCHA answer is used in real time to check whether the "self-driving" car is about to arrive at an intersection with a stop sign. This information is pretty critical, as failing to mark the stop could cause an accident. The user is unlikely to respond to the CAPTCHA in time to avert disaster, not to mention that any interruption to the car's internet connection could prove fatal. [[:Category:Self-driving cars|Self driving cars]] have become a recurrent theme on xkcd.

The system depicted is a {{w|Wizard of Oz experiment}} (as is the "Mechanical Turk" which a popular crowdworking system is named after) whereas actual self-driving cars, to the extent that they can use reCAPTCHA-style human detection systems, would involve an asynchronous decision system. Other synchronous decision systems which actually exist are political voting and money as a token of the exchange value of trade.

The title text explains that this method could be called "crowdsourced steering", {{w|crowdsourcing}} meaning sending the data on the internet to let several users provide their ideas and input on a problem. People would naturally suspect that this is considerably less safe than a car which is actually capable of self-driving; if the internet can barely [[1333: First Date|collectively steer a videogame character]], what chance do they have steering an actual, physical vehicle?

This also suggests that [[Randall]] is a bit skeptical of the current stage of AI, as this doubts whether the AI technology really is working in the way that we expect. It also comments on how what we call 'progress' actually is putting our work onto other people.

==Transcript==
:[Inside a frame there is the following text above an image:]
:To complete your registration, please tell us whether or not this image contains a stop sign:

:[The square image is a drawing of a road leading up to a sign post with a hard to read word at the top part of the eight-sided sign. The sign also has two smaller signs left and right with unreadable text. The image is of poor quality, but trees and other obstacles next to the road can be seen. Darkness around the edges of the image could indicate that it is night and the landscape is only lit up by a cars head lights.]
:Sign: Stop

:[Beneath the image there are two large gray buttons with a word in each:]
:No Yes

:[Beneath the buttons are the following text:]
:Answer quickly – our self-driving car is almost at the intersection.

:[Caption beneath the frame:]
:So much of "AI" is just figuring out ways to offload work onto random strangers.

{{comic discussion}}

[[Category:Self-driving cars]]
[[Category:Artificial Intelligence]]
[[Category:CAPTCHA]]

Talk:2723: Outdated Periodic Table

2023-01-12T06:28:25Z

Sabik:

https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis BBN did only produce unstable Berylium-7 with a half-life of 53.22 days. Thus after 30 minutes there was still plenty of Be-7 left.
--[[Special:Contributions/172.71.160.38|172.71.160.38]] 15:36, 11 January 2023 (UTC)

"unnilium" is a reference to "unnilunium", which was the name for Mendelevium (atomic number 101; from "un nil un", 1-0-1) before it was given a formal name. Therefore the 6th new element referenced, on top of the 4 already in the table, would be #10, or "un nil", or unnilium. [[Special:Contributions/172.71.190.132|172.71.190.132]]

"Pentium" was also the first non-numeric name for the Intel family. Before that, it was the 80486/i486. [[Special:Contributions/172.70.134.195|172.70.134.195]] 16:17, 11 January 2023 (UTC)

I have a science textbook at home that doesn't have ''any'' elements in a periodic table, though you'd think it should. It has a very nice ''list'' of elements (with dodgy details, e.g. I think at least one of them was later proven to be two separate but tricky to isolate elements), but was written prior to the popularisation of Mendeleev's table. (i.e. post-1869, but not by much!) Now, obviously, I don't want to diss Randall's humour, but I have so few such retro-geeky things I can brag about so I just wanted to mention this in passing. (Also, when I actually did my own chemistry, the lab wall had a PT on it that featured the element "{{w|Dubnium|Hahniun}}", and some others since replaced/resolved differently. I sometimes still forget myself and refer to the wrong names if I have to answer trivia questions about them ) [[Special:Contributions/172.70.91.127|172.70.91.127]] 23:45, 11 January 2023 (UTC)
: It's a proleptic periodic table [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]])

Is there a category for comics about the Periodic Table? I recall one from a year or so ago where the symbols were replaced with ones based on the modern names for the elements. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 05:29, 12 January 2023 (UTC)

2719: Hydrogen Isotopes

2023-01-03T05:01:55Z

Sabik: /* Explanation */ Add real/fictional column

{{comic
| number = 2719
| date = January 2, 2023
| title = Hydrogen Isotopes
| image = hydrogen_isotopes_2x.png
| imagesize = 442x250px
| noexpand = true
| titletext = Oops, All Neutrons is also known as Neutral Quadrium, Nydnonen, and Goth Tritium.
}}

==Explanation==
{{incomplete|Created by a BREAK ROOM DE BROGLIE MICROWAVE USER. Do NOT delete this tag too soon.}}

{{W|Hydrogen}} is the simplest of the chemical atoms, usually consisting of an electron orbiting an proton. This comic imagines other humorous fictional forms of hydrogen as follows:

{| class="wikitable"
! "Isotope"
! Real?
! Description
|-
|Hydrogen
|Yes
|Hydrogen is the most common {{w|isotope}} of hydrogen, with one proton and one electron, shown with the electron orbiting the proton.It is also known as Protium.
|-
|Deuterium
|Yes
|Deuterium is the second most common isotope of hydrogen, with one electron, and both a neutron and proton in its nucleus. About one of every 6,760 hydrogen atoms in water is deuterium.
|-
|Tritium
|Yes
|Tritium is the third most common isotope of hydrogen, with one electron, and a nucleus of one proton and two neutrons, for an atomic mass of three {{w|Dalton (unit)|daltons}}. It is radioactive with a half-life of about twelve years, and is quite rare.
|-
|Ium
|No
|This imaginary isotope consists of one electron orbiting around nothing. The name relates to the fact that the two heavier isotopes are named from a prefix designating the number of {{w|nucleons}} followed by the suffix "-ium", which is sometimes used satirically, e.g., in "unobtainium."
|-o
|Wheelium
|No
|This fictional form consists of a proton, electron, and neutron orbiting around nothing, shaped similarly to a wheel.
|-
|Instant hydrogen (ready in 15 minutes)
|Yes, but rarely
|This is just a single neutron. Unbound neutrons will take about fifteen minutes to decay into a proton, an electron, and a neutrino, which ''can'' then form into a hydrogen atom, [https://van.physics.illinois.edu/ask/listing/1207 but do only four times in a million.] The name is likely a reference to "instant" meals that require less preparation time than traditional varieties, e.g., instant noodles.
|-
|Hydrogen (maximum strength)
|No
|This fictional isotope consists of a proton, an electron, and what appear to be at least 14 neutrons. This isotope's proton would not be bound to all the neutrons. It would immediately {{w|Nuclear drip line|drip}} away most of them.
|-
|Oops, All Neutrons
|Maybe
|This fictional form consists of four neutrons, a {{w|tetraneutron}}, with one orbiting around a group of three. The name is likely a reference to an American breakfast cereal called {{w|Cap'n Crunch#Variations|Oops! All Berries}}. The title text states other names of this form are Neutral Quadrium, Nydnonen, and Goth Tritium.
|}

{{notice2|The Mountain View, California Public Library is hosting an online chat with [[Randall Munroe]] Tuesday, January 31 at 11am Pacific. [https://libraryc.org/mountainviewlibrary/22032 Register here to send your question(s) to the moderators.]|image=Crystal Project Agt announcements.png}} 

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

There are 8 drawings of atoms, arranges 4 across and 2 down, in the Planetary model. Each has a label underneath. Here, they are listed left-to-right top-to-bottom.

1 electron, 1 proton: Hydrogen

1 electron, 1 proton, 1 neutron: Deuterium

1 electron, 1 proton, 1 neutron: Tritium

1 electron only: ium

1 electron, 1 proton, 1 neutron, all orbiting together around nothing: Wheelium

1 proton only: Instant Hydrogen (ready in 15 minutes)

1 proton, 1 electron, lots of neutrons: Hydrogen (Maximum Strength)

1 neutron orbiting 3 other neutrons: Oops, all neutrons
{{comic discussion}}
[[Category:Chemistry]]

2712: Gravity

2022-12-17T03:13:02Z

Sabik: /* Explanation */ B-612 also a reference to xkcd #618

{{comic
| number = 2712
| date = December 16, 2022
| title = Gravity
| image = gravity_2x.png
| imagesize = 740x700px
| noexpand = true
| titletext = It's a long way down.
}}

*To experience the interactivity, visit the [http://xkcd.com/2712/ original comic].
==Explanation==
{{incomplete|Created by SPACE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
In this comic, you can fly a small spaceship to visit different planets using your arrow keys. Tiny spheres appear in the direction of nearby planets as a guide.

Throughout the solar system are coins that change your rocket ship into different rockets and even non-space based vehicles, including humans.

This comic was released as a promotion for Randall's new book [https://xkcd.com/what-if-2/ What If? 2], which was released in September and is available for purchase. Many of the planets contain references to various What If? articles.

The following is an incomplete list of planets and other significant features:

Starting planet

Europa

B-612 (The Little Prince reference; also a reference to [[618: Asteroid]])

Dog park planet (What If? 2 reference)

What If? 2 scenario planet

Sun's core (What If? 2 reference)

The Sun

A cluster of black holes

Soup system (What If? 2 reference)

Earth without Japan (What If? 2 reference)

Just Japan (What If? 2 reference)

A blob labeled "Pigeons"

Starship Enterprise (Star Trek reference)

Dinosaur planet (Dinosaur Comics and Jurassic Park reference)

What If? 1 scenario planet

Cat blocking traffic flowing through portals

A tree larger than the planet it's growing on

Edge of the Universe (actually just a planet labeled "Edge of the Universe")

Milliways (Hitchhiker's Guide to the Galaxy reference)

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

Welcome!

To celebrate the world of what if? 2, here is your very own planet to explore!

Give someone the science question-and-answer book what if? 2 for Christmas:
xkcd.com/whatif2

{{comic discussion}}
[[Category:Space]]
[[Category:Book promotion]]
[[Category:Interactive comics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]

2687: Division Notation

2022-10-20T03:52:03Z

Sabik: /* Explanation */ Add explanation of fourth line

{{comic
| number = 2687
| date = October 19, 2022
| title = Division Notation
| image = division_notation_new_2x.png
| imagesize = 235x310px
| noexpand = true
| titletext = Science tip: Scientists hardly ever use the two-dot division sign, and when they do it often doesn't even mean division, but they still get REALLY mad when you repurpose it to write stuff like SALE! ALL SHOES 30÷ OFF!
}}

==Explanation==
{{incomplete|Created by a GROUP OF SCHOOLCHILDREN DIVIDED AMONGST THEMSELVES - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic pokes fun at some of the ways to write the {{w|Division (mathematics)|division}} operation in math. In this comic, Randall has used A as the dividend (the number being divided) and B as the divisor (the number that A is divided by).

The first two are respectively the {{w|division sign}} (÷) and {{w|long division}} symbol. (Note: the long division symbol is only used in some countries). These methods of division are often used by school children as the first ÷ is what people learn when first learning division, and the second long division symbol is usually the first type of long division learned (it's easier to do it visually on paper that way).

The third line is the way the division is often written in software code. The 4 standard operations in programming usually are +, -, *, /. This one was missing in the first version of the comic. This is most commonly seen in regular mathematics as it somewhat saves space, and is easy to type with the slash key.

The fourth line is how the division is often hand-written; the A smaller and somewhat higher, the B smaller and somewhat lower, in order to suggest fraction notation (as on the fifth line) without either taking up more vertical space or writing so small as to be illegible. This is hard to achieve on a computer, particularly in situations where formatting is not available; Unicode provides some superscript and subscript characters, so someone familiar with it might use it to write fractions such as ²²⁄₇, but this is rarely used in everyday life (and the fraction A/B cannot be written this way; there is a superscript A, but no subscript B).

The fifth notation is the way division is written in science, dividend on top line and divided on bottom line. This is the closest format to how a {{w|Fraction|fraction}} would be written. This format is mostly used in written math, as it can't be typed without something like MathML or LaTeX.

The sixth notation uses a negative exponent. The exponent -1 has the same effect as dividing by the base. It can be used to keep an equation on 1 line.

The final form of notation appears to be not a simple notation for division. Rather, it looks like a definition of a notion of division which is customized to a particular setting. This situation is likely to occur in abstract algebra, where one might have to define what "division" might mean for two elements of a mathematical object such as a group, ring, or magma. One example would be an object G, such that, for two elements A and B of G, "A divided by B" is defined as an element C such that CB=A, or alternatively as an element C such that BC=A. These definitions might differ if multiplication in G is not commutative. Furthermore, if such a C is not unique, a function F(A,B) might have to be chosen to select a unique value for "A divided by B" for each A and B. Thus, the F(A,B) in the comic might not even refer to a uniquely defined operation, but simply to the property of a function F(A,B) that is a valid division operation on G, given some definition of division.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Division notation
:A÷B
:B⟌A Schoolchild.
:A/B Software engineer.
:A⁄B Normal person or Unicode enthusiast.
:A over B Scientist.
:AB-1 Fancy scientist.
:F(A, B) such that F(G)= (text getting smaller) Oh no, run

{{comic discussion}}

[[Category:Math]]
[[Category:Science]]
[[Category:Programming]]
[[Category:Science tip]]

2682: Easy Or Hard

2022-10-09T12:06:46Z

Sabik: /* Explanation */ +nautical almanac for position of Mars

{{comic
| number = 2682
| date = October 7, 2022
| title = Easy Or Hard
| image = easy_or_hard_2x.png
| imagesize = 740x400px
| noexpand = true
| titletext = "Friction-driven static electrification is familiar and fundamental in daily life, industry, and technology, but its basics have long been unknown and have continually perplexed scientists from ancient Greece to the high-tech era. [...] To date, no single theory can satisfactorily explain this mysterious but fundamental phenomenon." --Eui-Cheol Shin et. al. (2022)
}}

==Explanation==
{{incomplete|Created by THE EIFFEL TOWER TAKING A TYLENOL - Do NOT delete this tag too soon.}}

This comic uses a table to compare the perceived difficulty of various questions with how easily they're answered in real life. [[Randall]] has a long history of comics with similar themes, comparing perceptions to reality. In this case, both the perception and the reality are divided into three levels of difficulty, giving a total of nine categories. Accordingly three of the problems listed are effectively as difficult as one would expect, and the remaining six are not. All three of the questions whose answers are "actually pretty easy to find out" relate to the Eiffel Tower, though there's no apparent theme among the other six questions.

It's likely that this comic was at least partially inspired by writing the books ''[[How To|How To: Absurd Scientific Advice for Common Real-World Problems]]'', [[what if|''What if?'', and ''What If? 2'']], which was published just a few weeks before this comic. These books involve answering very elaborate questions from a scientific point of view. This process likely emphasized that some really strange questions are actually difficult to answer, while some questions that seem simple continue to confound scientific knowledge. ''What if? 2'' mentions the fact that no one understands why static charges separate.

{| class="wikitable"
|-
! Question !! Perceived Difficulty !! Real Difficulty !! Explanation
|-
|How tall is the Eiffel Tower?||Easy||Easy||The height of any structure that can be easily observed can be calculated without much difficulty. The Eiffel Tower was constructed to be the centerpiece of the {{w|1889 World's Fair}}. At the time of its construction, it was the tallest man-made structure on earth, which meant that its height was widely publicized since it was first constructed (330 meters, or 1083 feet). This number is widely published, and easily confirmed.
|-
|Where was Mars in the sky from Paris on the day the Eiffel Tower opened?||Difficult||Easy||The date of the opening of the tower to the public is well known (May 6, 1889). Since the motions of the planets are predictable, it's clear that calculating the answer should be possible, but it involves enough factors that one might expect it to be very difficult. However, thanks to the existence of [https://in-the-sky.org/skymap.php?no_cookie=1&latitude=48.85&longitude=2.35&timezone=1.00&year=1889&month=5&day=6&hour=9&min=0&PLlimitmag=2&zoom=182&ra=3.78242&dec=20.26465 online tools], which automatically calculate exactly this sort of thing, finding the answer is quite easy. (It was in the constellation of Taurus, and extremely close to where the Sun also was in the sky during that time so probably not easily directly observable). Alternately, to use the tools available at the time, one might check a nautical almanac for 1889, which gives the position of the major planets (and various other celestial bodies) in the sky throughout the year.
|-
|How much does the {{w|Eiffel Tower}}'s gravity deflect baseballs in Boston?||Near Impossible||Easy||This problem sounds extremely specific and esoteric, concerning an effect far too small for direct experimentation. But in theory, it's actually a very simple physics problem. {{w|Newton's law of universal gravitation|Gravitational acceleration}} is determined entirely by masses and distance, and here even the mass of the baseball can be ignored. Since the mass of the Eiffel Tower and the geographic details of both the tower in Paris and any given location in Boston (perhaps {{w|Fenway Park}}, a famous baseball stadium) are easy to look up, the calculation is quite simple.
|-
|How does {{w|general anesthesia}} work?||Easy||Difficult||While biology is always complex, inducing unconsciousness seems relatively simple. In fact, keeping a person unconscious and insensate without causing permanent damage or death is a difficult proposition, requiring a medical specialist. Despite this field being well-established, it might surprise people to know that {{w|Theories of general anaesthetic action|the mechanism of general anesthesia}} is still the subject of research, and recent studies have revealed things that we didn't previously understand.
|-
|How many ants are there?||Difficult||Difficult||While the existence of ants is a mundane part of life for many people, there are so many of them that coming up with a total number of ants in the whole world sounds exceedingly difficult. It is, in fact, a difficult problem, but experts have done a significant amount of work and have come up with well-founded estimates [https://phys.org/news/2022-09-ants-earth-quadrillion.html in the range of 20 quadrillion ants on earth].
|-
|What time of year did the {{w|Cretaceous–Paleogene extinction event|Cretaceous impact}} happen?||Near Impossible||Difficult||The "Cretaceous impact" happened approximately 66 million ago. The margins of error on calculating something that ancient are necessarily thousands of years wide at least, the notion of determining the time of year seems impossible. In fact, the problem is a difficult one, but many of the animals killed in the impact were fossilized, and comparing those fossils to seasonal growth cycles [https://www.science.org/content/article/springtime-was-season-dinosaurs-died-ancient-fish-fossils-suggest has led to the suggestion that the impact happened in spring in the northern hemisphere.]
|-
|Why does your hair get a static charge when you rub it with a balloon?||Easy||Near Impossible||Inducing a {{w|Static electricity|static charge}} by {{w|Triboelectric effect|rubbing together two materials}} is a method that's been known since ancient times. Since human hair has a marked tendency to develop a positive charge, and the latex commonly used in balloons tends to develop a negative charge, rubbing the two together is a very simple way to create an electric field. This process is so simple that it's used for both party tricks and as a fun demonstration of electrical phenomena. Because of this simplicity, most people would assume that the phenomenon is well understood. So it's surprising that the actual mechanism remains an unsolved problem in physics. This also has previously been mentioned in [[1867: Physics Confession]]. The title text quotes [https://www.researchgate.net/publication/360674587_Derivation_of_a_governing_rule_in_triboelectric_charging_and_series_from_thermoelectricity a paper] explaining that, as common as this phenomenon is, there's still no theory that can adequately explain what we observe.
|-
|How does {{w|Tylenol (brand)|Tylenol}} work?||Difficult||Near Impossible||Tylenol is a brand name for {{w|Paracetamol|paracetamol, also known as acetaminophen}}, a drug commonly sold without prescription for pain relief and fever reduction. This drug has been widely used since 1950, and has been well established as being both effective and safe when used properly. Although one would expect the biological mechanism for any drug to be complicated, most people would assume that a drug that's been widely used and studied for so long to be well-documented. Surprisingly, however, the precise action still isn't fully understood.
|-
|How can {{w|Theory of relativity|relativity}} be reconciled with {{w|quantum mechanics}}?||Near Impossible||Near Impossible||This remains one of the {{w|Theory of everything|great unsolved questions}} in physics. The problem sounds almost unsolvable to laypeople, and remains unsolved even to experts in the field.
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
{| class="wikitable"
|-
! !! Actually pretty easy to find out !! Very hard, but there have been recent breakthroughs !! Extremely hard, currently unsolved
|-
! Sounds borderline unsolvable
|How much does the Eiffel Tower's gravity deflect baseballs in Boston?||What time of year did the cretaceous impact happen?||How can relativity be reconciled with quantum mechanics?
|-
! Sounds pretty hard, but you'd assume someone knows
|Where was Mars in the sky from Paris on the day the Eiffel Tower opened?||How many ants are there?||How does Tylenol work?
|-
! Sounds like it would be easy to look up
|How tall is the Eiffel Tower?||How does general anesthesia work?||Why does your hair get a static charge when you rub it with a balloon?
|}

{{comic discussion}}
[[Category:Charts]]
[[Category:Science]]
[[Category:Animals]]
[[Category:Medicine]]
[[Category:Physics]]
[[Category:Astronomy]]

Talk:2507: USV-C

2022-06-29T01:08:46Z

Sabik: Link to real-world prototype of the connector

I just did my first edit! It'll definitely get changed, but I guess this is good enough for a start

[[Special:Contributions/162.158.89.204|162.158.89.204]] 16:30, 25 August 2021 (UTC)

that's not as absurd as it sounds. there are optical usb cables which work by converting the usb signals to and from light signals.[[Special:Contributions/162.158.92.83|162.158.92.83]] 16:48, 25 August 2021 (UTC)

I bet this is going to be an xkcd that gets recreated in real life.

[[Special:Contributions/108.162.215.87|108.162.215.87]] 17:01, 25 August 2021 (UTC)

There are ultraviolet LED lamps that are powered at 5V with an USB connector. xkcd in real life it's already done.
[[Special:Contributions/141.101.105.27|141.101.105.27]] 17:57, 25 August 2021 (UTC)
: I've been unable to find one with a hardwired male USB-C plug in a quick Google search. Though, there are many portable UV-C lamps which would count as USB-C socket to UV-C, so you could add on a USB-C plug-plug adapter and emulate this XKCD with two chained adapters. [[Special:Contributions/172.69.71.69|172.69.71.69]] 19:20, 25 August 2021 (UTC)

Am I the only one to think "from C to shining C"? And I'm not even American. [[Special:Contributions/141.101.76.209|141.101.76.209]] 20:00, 25 August 2021 (UTC)

It could be as simple as a UV lightbox integrated into a USB EPROM programmer. Have a few in the back erasing while you're programming a few in the front. --[[User:Tepples|Tepples]] ([[User talk:Tepples|talk]]) 22:42, 25 August 2021 (UTC)

It could be that the light flashes on and off for data or something. --[[Special:Contributions/198.41.238.51|198.41.238.51]] 05:35, 26 August 2021 (UTC)

Regarding getting it backwards the first time: an old engineer I worked with back at the beginning of my career 40 years ago used to say (speaking of serial cable pins, but applicable here also): always just try connecting it at random. That way you'll have a 50% chance of being right. If you try to figure it out first, your odds go way down. [[User:Gbisaga|Gbisaga]] ([[User talk:Gbisaga|talk]]) 13:03, 27 August 2021 (UTC)

Germ killing can't be connected to COVID. COVID is a virus, not a germ. --[[Special:Contributions/141.101.77.69|141.101.77.69]] 15:19, 28 August 2021 (UTC)

: https://www.merriam-webster.com/dictionary/germ Definition 3: : "a microorganism causing disease : a pathogenic agent (such as a bacterium or virus)" [[User:Kempsridley|Kempsridley]] ([[User talk:Kempsridley|talk]]) 16:02, 2 September 2021 (UTC)

Is this article still incomplete, or can the tag be removed now? [[User:Kempsridley|Kempsridley]] ([[User talk:Kempsridley|talk]]) 16:10, 2 September 2021 (UTC)

Looks like [https://twitter.com/RealSexyCyborg/status/1539124570460143616 someone's actually prototyping this], using Far-UVC (222nm) which is [https://www.kobe-u.ac.jp/research_at_kobe_en/NEWS/collaborations/2020_04_07_01.html safe for human skin and eyes] [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 01:02, 29 June 2022 (UTC)

2507: USV-C

2022-06-29T01:07:38Z

Sabik: /* Explanation */ Note that far-UVC is safe for human skin and eyes

{{comic
| number = 2507
| date = August 25, 2021
| title = USV-C
| image = usv_c.png
| titletext = Ultra-Serial Violet C light is unpolarized, so you don't have to flip the polarizing filter over when you get the orientation wrong the first time.
}}

==Explanation==
This is the fourth installment in the series of [[:Category:Cursed Connectors|Cursed Connectors]] and presents Cursed Connectors #280: USB-C to UV-C. It follows [[2503: Memo Spike Connector]] (#102) and was first followed just a bit more than half a year later by [[2589: Outlet Denier ]] (#78).

This comic depicts a cable that converts from USB-C (at the top of the picture) to UV-C (at the bottom).

{{w|USB-C}} is a rotationally symmetrical {{w|Universal Serial Bus}} (USB) connector. {{w|Ultraviolet#UVC|UV-C}} is a range of {{w|ultraviolet light}} with wavelengths between 100 and 280 nm. This is often used as a germicide, so this comic may also be related to the [[:Category:COVID-19|COVID-19]] pandemic. The U.S. Food and Drug Administration (FDA) has an [https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/uv-lights-and-lamps-ultraviolet-c-radiation-disinfection-and-coronavirus infosheet] with information about these devices and COVID-19. And the connector number (280) is likely chosen because it is the boundary between UV-C and UV-B in nanometres.

Similar cables actually exist, with a USB port at one end to power a small (usually visible light) lamp at the other. A cable with a UV-C lamp could, as noted above, be useful for disinfecting surfaces. However, the depicted design would be problematic because it would expose the user's skin and eyes to harmful ultraviolet radiation, unless it's specifically Far-UVC (222nm, [https://www.kobe-u.ac.jp/research_at_kobe_en/NEWS/collaborations/2020_04_07_01.html safe for human skin and eyes]).

Unless there is more to the UV-C end than indicated, the cable seems not to have use in bidirectional communication (even to confirm that it is {{w|TOSLINK|plugged in}} or {{w|Infrared_Data_Association|shone upon}} some suitable optical transceiver) so in any {{w|Li-Fi|data transfer situation}} it could be a limited-range broadcast-only system at best - which has its uses in certain niche cases.

The title text mentions that the UV-C is {{w|Polarization_(waves)|unpolarized}}. This is a pun with two uses of the term polarized. When referring to a connector 'polarization', or absence of it, it means that USB-C does not force you to use a single {{w|Electrical_connector#Keying|correct orientation}} when using it, i.e. you don't have to turn it "right-side-up" like USB-A or USB-micro.

It also refers to the use of a {{w|Polarizing filter (photography)|polarizing filter}} which takes unpolarized light waves and blocks out the waves that are not oriented in the same direction. These are used in sunglasses and photography to eliminate glare and enhance the image. These filters do need to be oriented in a specific direction in order to have the desired effect of passing/blocking a given polarization, perhaps to separate two perpendicularly orientated 'channels' that need to be unmixed exactly knowing the respective orientation of the two signals (''or'' exactly 180° out, which is what USB-C effectively allows for at present).

The light could also have been {{w|Circular_polarization|circularly polarized}}, which allows 'left' and 'right' rotating polarizations to simultaneously carry separate signals, but {{w|3D_film#Polarization_systems|not require the same strict orientation}} to operate properly, at all, so long as arbitrary mirrors are not involved at any stage of the optical path. Regardless, the implication here is that there is ''no'' deliberate rationalization of the light to contend with, anyway, which seems to be just making a positive point out of a potentially lost opportunity to double any intended signal bandwidth. The name "Ultra-Serial Violet..." could be read as consciously eschewing ''all'' attempts at parallelism, including talkback.

==Transcript==
:[A cable with a curled wire displays the end of both of its connectors. The top end has a USB-C connector and the bottom end has a UV-C LED. The UV light is shown coming out of this end with a hazy blue circle around a white middle. The lamp is also bluish. Above is a title and below is a label.]
:Cursed Connectors #280
:USB-C to UV-C

{{comic discussion}}

[[Category: Comics with color]]
[[Category: Cursed Connectors]]

Talk:2507: USV-C

2022-06-29T01:02:08Z

Sabik: Link to real-world prototype of the connector

I just did my first edit! It'll definitely get changed, but I guess this is good enough for a start

[[Special:Contributions/162.158.89.204|162.158.89.204]] 16:30, 25 August 2021 (UTC)

that's not as absurd as it sounds. there are optical usb cables which work by converting the usb signals to and from light signals.[[Special:Contributions/162.158.92.83|162.158.92.83]] 16:48, 25 August 2021 (UTC)

I bet this is going to be an xkcd that gets recreated in real life.

[[Special:Contributions/108.162.215.87|108.162.215.87]] 17:01, 25 August 2021 (UTC)

There are ultraviolet LED lamps that are powered at 5V with an USB connector. xkcd in real life it's already done.
[[Special:Contributions/141.101.105.27|141.101.105.27]] 17:57, 25 August 2021 (UTC)
: I've been unable to find one with a hardwired male USB-C plug in a quick Google search. Though, there are many portable UV-C lamps which would count as USB-C socket to UV-C, so you could add on a USB-C plug-plug adapter and emulate this XKCD with two chained adapters. [[Special:Contributions/172.69.71.69|172.69.71.69]] 19:20, 25 August 2021 (UTC)

Am I the only one to think "from C to shining C"? And I'm not even American. [[Special:Contributions/141.101.76.209|141.101.76.209]] 20:00, 25 August 2021 (UTC)

It could be as simple as a UV lightbox integrated into a USB EPROM programmer. Have a few in the back erasing while you're programming a few in the front. --[[User:Tepples|Tepples]] ([[User talk:Tepples|talk]]) 22:42, 25 August 2021 (UTC)

It could be that the light flashes on and off for data or something. --[[Special:Contributions/198.41.238.51|198.41.238.51]] 05:35, 26 August 2021 (UTC)

Regarding getting it backwards the first time: an old engineer I worked with back at the beginning of my career 40 years ago used to say (speaking of serial cable pins, but applicable here also): always just try connecting it at random. That way you'll have a 50% chance of being right. If you try to figure it out first, your odds go way down. [[User:Gbisaga|Gbisaga]] ([[User talk:Gbisaga|talk]]) 13:03, 27 August 2021 (UTC)

Germ killing can't be connected to COVID. COVID is a virus, not a germ. --[[Special:Contributions/141.101.77.69|141.101.77.69]] 15:19, 28 August 2021 (UTC)

: https://www.merriam-webster.com/dictionary/germ Definition 3: : "a microorganism causing disease : a pathogenic agent (such as a bacterium or virus)" [[User:Kempsridley|Kempsridley]] ([[User talk:Kempsridley|talk]]) 16:02, 2 September 2021 (UTC)

Is this article still incomplete, or can the tag be removed now? [[User:Kempsridley|Kempsridley]] ([[User talk:Kempsridley|talk]]) 16:10, 2 September 2021 (UTC)

Looks like [someone's actually prototyping this|https://twitter.com/RealSexyCyborg/status/1539124570460143616], using Far-UVC (222nm) which is [safe for human skin and eyes|https://www.kobe-u.ac.jp/research_at_kobe_en/NEWS/collaborations/2020_04_07_01.html] [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 01:02, 29 June 2022 (UTC)

2632: Greatest Scientist

2022-06-14T02:06:24Z

Sabik: /* Explanation */ Add "measured the shadow" experiment

{{comic
| number = 2632
| date = June 13, 2022
| title = Greatest Scientist
| image = Greatest Scientist.png
| titletext = "Ow! One of the petri dishes I left on the tower railing fell and hit me on the head. Hey, that gives me an idea..."
}}

==Explanation==
{{incomplete|Created by HISTORY'S WURST SCIENTIST - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic pretends that many (6 by my count) of history's greatest scientists were the same person, and says that this person was the greatest scientist in history. A combination of six of the greatest scientists ever would most likely be the greatest scientist ever.{{Citation needed}}

These scientists are most likely {{w|Galileo Galilei}}, {{w|Benjamin Franklin}}, {{w|Alexander Fleming}}, {{w|Ivan Pavlov}}, {{w|Eratosthenes}}, and {{w|Isaac Newton}}.

The floor is noticable curved in this comic, as the curvature of Earth is mentioned and measured, thus requiring curvature.

Humorously combining multiple science experiments into one was also a punchline in [[1584: Moments of Inspiration]]. Curved floors were also mentioned in [[2412: 1/100,000th Scale World]]
{| class="wikitable"
|+ List of experiments in the comic
|-
! Experiment in comic !! Experiment in reality !! Meaning !! Scientist
|-
| measured the shadow || measuring the length of the shadow of a building and the length of the shadow of another nearby object of known height can be used to calculate the height of the building || the lengths of the sides of similar triangles are proportional to each other || ???
|-
| the Leaning Tower of Pisa || {{w|Galileo}} conducted [https://en.wikipedia.org/wiki/Galileo%27s_Leaning_Tower_of_Pisa_experiment an experiment] at the Leaning Tower of Pisa to measure whether the rate at which objects fall is dependent on weight or is consistent. || Galileo found that objects with different weights fall at the same rate, disproving Aristotle's theory which purported the opposite. However, {{w|Viviani}} had already discovered this. Galileo's experiment further developed experimentation in science, in opposition to the then-prevailing view that knowledge is learned by studying the writings of the ancients.|| {{w|Galileo Galilei}}
|-
|while flying a kite into a distant thunderstorm, where lightning || In June 1752, Benjamin Franklin performed his famous {{w|kite experiment}} in which he attached a conductive wire to a kite and flew it near a thunderstorm. Attached to the kite was a key, which was further attached to a {{w|Leyden jar}}. || While the kite was not hit by lightning, "Franklin did notice that loose threads of the kite string were repelling each other and deduced that the Leyden jar was being charged." This is sometimes considered the discovery of the fact that lightning contains/is electricity. || {{w|Benjamin Franklin}}
|-
| caused two moldy petri dishes to fall || In August 1928, Alexander Fleming put ''Staphylococcus aureus'' into multiple petri dishes and then left to go on holiday/vacation. On September 3, he returned and found that one plate had mould on it. This plate was the only one that did not have ''S. aureus'' bacteria in it. He later repeated this experiment and {{w|History_of_penicillin#The_breakthrough_discovery|the result was confirmed}}. || The mould that Fleming had discovered produced penicillin, an antibiotic. This was the first time that a substance had been discovered that could ''reliably'' treat bacterial infections, having a huge impact on medicine across the world. || {{w|Alexander Fleming}}
|-
| onto a bell next to a salivating dog || [https://www.simplypsychology.org/pavlov.html In 1902 Ivan Pavlov conducted a study on dog reflexes] by giving dogs food and simultaneously ringing a bell. When the dog smelled and saw the food, it started salivating. Eventually, simply ringing the bell made the dog salivate, as the dog had associated the bell ringing with food. Pavlov also performed other, less humane experiments on other dogs. || This was the discovery of {{w|classical conditioning}}, where a stimulus is paired with an unrelated other thing through repeated exposure. The subject will eventually react to the unrelated thing in the absence of the stimulus. This is an example of taught reflexes, where a subconsious reaction like a reflex or instinct is taught. || {{W|Ivan Pavlov}}
|-
| whose shadow angle determined the circumference of the Earth || |In the 200s BCE, the Greek philosopher Eratosthenes {{w|Earth's_circumference#Eratosthenes|measured the circumference of the Earth}}. While his exact method has been lost to time, a simplified version remains: At high noon on the summer solstice in Syene, Egypt, the sun was almost directly overhead. This was confirmed with a sundial. 5,000 stadia away in Alexandria, at the same time, the angle of the sun was measured with another sundial and converted into a fraction of the Earth's circumference. Some simple multiplication could then yield the circumference of the Earth. || The distance Eratosthenes calculated for the circumference of Earth was 250,000 stadia. This estimate was either 2.4% low or 0.8% high compared to modern knowledge, depending on whether he used Greek or Egyptian stadia - a remarkably accurate estimate for the time. || {{w|Eratosthenes}}
|-
| (Title text) fell and hit me on the head. Hey, that gives me an idea... || Sir Isaac Newton, an inventor of calculus and discoverer of his famous {{w|Newton's laws of motion|Laws of Motion}}, also described how {{w|gravity}} works. The story goes that in 1726 while in contemplation in his garden, {{w|Isaac_Newton#Apple_incident|Newton saw an apple fall}}. Rather than ignoring it, he wondered what ''exactly'' caused the apple to fall and why it fell straight down. This led him to investigate gravity, eventually publishing ''{{w|Philosophiæ Naturalis Principia Mathematica}}'', or simply the ''Principia''. || Newton went on to contemplate gravity, deducing the {{w|Law of Universal Gravitation}} - which includes that the same force that caused the apple to fall also caused celestial bodies to orbit as they do. || Sir {{w|Isaac Newton}}
|}

==Transcript==
{{incomplete transcript |Please change this comment when editing this page. Do NOT delete this tag too soon.}}

:[On the left of the panel, there are some buildings and trees representing Pisa, Italy. One of these buildings is the Leaning Tower of Pisa. Below the tower are some mathematical symbols and angles, marking its shadow as L1. Attached to the top of the tower, there is a kite string. The kite is in the top right, next to a thunderstorm. Falling from the kite are two disks which fall onto a bell underneath. The bell goes "Ding! Ding!" Next to the bell is a dog. There are more lines and mathematical symbols coming off the dog, marking its shadow as L2. The ground is noticeably curved.]

:[Caption below the panel:]
:History's greatest scientist was probably that one who measured the shadow of the Leaning Tower of Pisa while flying a kite into a distant thunderstorm where lightning caused two moldy Petri dishes to fall onto a bell next to a salivating dog whose shadow angle determined the circumference of the Earth.

{{comic discussion}}
[[Category: Science]]

Talk:2519: Sloped Border

2021-09-24T06:48:10Z

Sabik: What does "vertical" even mean?

I might be old-fashioned, but I've always wanted to live in Mandelbrotistan 3D. [[Special:Contributions/162.158.89.156|162.158.89.156]] 15:49, 23 September 2021 (UTC)

I would make the country's border an Alexander horned sphere. [[Special:Contributions/108.162.221.245|108.162.221.245]] 03:21, 23 September 2021 (UTC)

:Waaait ... how can we define the border to maximize area of both countries? I'm talking non-measurable sets invoking something like {{w|Banach–Tarski paradox}} here ... -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 00:01, 24 September 2021 (UTC)

At least this border doesn't have [https://youtu.be/Mw44wHG4KOc thickness]. --[[User:Angel|Angel]] ([[User talk:Angel|talk]]) 04:48, 23 September 2021 (UTC)
-yet [[Special:Contributions/172.69.55.107|172.69.55.107]] 05:46, 23 September 2021 (UTC)

GIS: Geographic Information System, that are the systems where maps (and the borders) are defined. They won't care much though, because for them the ground information is the relevant one.
Once you get into air, you'll get a problem, because if the border is very sloped, and not in average straight, then an airplane might still be in the airzone of a different country than where it's flying over. Which will cause all kinds of problems, security wise.
Liechtenstein might loose all control over its airspace, yet their inhabitants want safety even from aircraft flying above them.
Can't imagine that going well, but bureaucrazy is that: it creates paperwork when it is not busy enough with the procedures it already created. [[Special:Contributions/172.69.55.107|172.69.55.107]] 05:46, 23 September 2021 (UTC)

Liechtenstein and air control is a bad example for the problems with sloped borders because it's quite often the case that the air space of one country is done by air space controllers of another country. In the case of Liechtenstein this is done by SKYGUIDE in Switzerland that is also doing it for southern parts of Germany (being responsible for the collision of two planes near Überlingen: https://en.wikipedia.org/wiki/2002_%C3%9Cberlingen_mid-air_collision) [[Special:Contributions/162.158.89.156|162.158.89.156]] 06:34, 23 September 2021 (UTC)

Wouldn't sloped borders also have interesting consequences underground when mining, building tunnels etc. ? [[Special:Contributions/162.158.88.239|162.158.88.239]] 08:39, 23 September 2021 (UTC)

I introduced into the explanation a hint of the more precise problem with airborne geometry upon spherical (or, possibly, geodesic) coordinates. The shallower the angle, the more possible that the 'curves with the ground' altitude calculation is to actually wrap itself all the way round the Earth before (presumably), whatever altitude limit there is to make space the same upper edge as International Waters are to horizontal edges. Taking the Liechtenstein case, as above, you could easily enclose them in a 'pyramidal' (or wedged, if not applied from all around them) air-claim by angling over them - ''or'' greatly increase their air-claim over neighbours if the angle is away. With inverse issues for the Mineral Rights issue. You need to agree in advance what happens when angled boundaries hit perpendicular ones, ''and'' whether the 'rhumbs' projected from the border mash together when equidistant points on a crinkly border project their own air-distance line. ''And'' if it is from an agreed surface level datum or local ground level, with the complications that arise from both cases. (Yeah, I originally thought there were about four different bones of contention that need to be ironed out in the codicil on curvature, but I now think there's about six of them needing strict definition, not counting the compound cases which further may need specifying in advance or forever requirev adhoc arbitration.) And none of this even takes account of Relativity and curved ''space'' frame of reference that might very subtly shift whatever reference you just agreed upon, if you let it go high enough. [[Special:Contributions/172.70.34.165|172.70.34.165]] 12:05, 23 September 2021 (UTC)

Should there be a part of the explanation talking about how GIS is already a nightmare? Because the hobby is "_new_ ways to make life a nightmare" [[Special:Contributions/162.158.75.159|162.158.75.159]] 13:35, 23 September 2021 (UTC)
:There should ; I expect it's because the borders are often defined by natural features, which may be very detailed AND changing in time. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 00:06, 24 September 2021 (UTC)

It's not worth wondering: is the boarder sloped across cardinal directions, like East to West, or is it sloped inward or outwards from the country in question? If the latter, outwards will make it like a funnel, meaning country A has greater airspace than its surface area at "ground" level. (Which is another consideration: where does the initial angle begin?) If sloped inwards, well then that country loses a lot of advantage. If it's based on cardinal directions... I do not want to consider how many complications that would create along various sections of the border. [[Special:Contributions/108.162.219.51|108.162.219.51]] 16:55, 23 September 2021 (UTC)

:Also, NERD SNIPE! [[Special:Contributions/108.162.219.51|108.162.219.51]] 16:56, 23 September 2021 (UTC)
:My presumption would be that the line-on-the-ground, however it winds around (e.g. following the centre of a river, the apex of a ridge or the point-to-point (with or without Great Circle adjustment) between two defining nodes) is a sequence of presumed horizontal line segments of arbitrary length, normalised to be parallel to the horizontal at the whatever ground elevation they cross. That line and the perpendicular through that line from the centre of the Earth (the vertical, by all accounts) thus define the third mutually perpendicular line that is the 'slopeward'(/antislopward) baseline. The defined angle indicates the inclination from the vertical on the vertical/slopeward plane.
:Where landforms complicate matters the border rises or falls across contours, or twists and turns with a convex and/or concave groundtrack, the dominant inclined border is that originating from the closest source-point wherever there is potentially conflict.
:If Cueball's border was around an enclave otherwise within his area of control, this would result in a tent-like (but strangely irregular) territorial enclosure (assuming not truncated by the Karman Line 'air limit', or similar). But I think he's content to make this just ''any'' shared border (e.g. the mostly 'straight' US-Canada fifty-whatever-parallel one) which means probably all other territorial limits (in that case, maritime) remain vertical (certainly not similarly leaning, in non-right-prismatic form) and except in a ''very few'' edge cases would end up dominating the slope-vs-vertical intersections.
:As to 'advantage' (except for the territory sloped away from), I don't think there really is one. At best, it makes true geofencing of drones a bit more complicated than saying "don't cross this line; don't go above/below these altitudes" for some doubtless functional reason. For the people in the RHS 'illustrative' sub-image, it seems to have no practical effect other than to identify limbs/other extremities as cross-border in rather more unusual slices of the body than a normal border-straddler would expect. [[Special:Contributions/162.158.159.11|162.158.159.11]] 22:33, 23 September 2021 (UTC)
Hmm, defining the calculation of the slope is tricky indeed. The commenter above suggests that the slope is relative to "vertical". However, the interpretation of "ground level" could deal with "level" meaning the ground slope, not the ground height. In other words, consider the slope on the side of a mountain. Let's suppose that in a local area, with a section of border running north/south, the ground is sloped 30 degrees to the east. Does that mean the 74 degree border is 104 degrees to the east at that point? The ground changing shape (whether due to natural erosion or bulldozers) could change the borders significantly.[[Special:Contributions/108.162.246.220|108.162.246.220]] 00:01, 24 September 2021 (UTC)

Sloped borders wouldn't be so weird, if the 3D component of the borders would follow the same rules as most 2D sea borders would do, which is that the border lies at a line of points equidistant from the coastlines.
If country A is flat and B has a mountain range and the border is at the foot of this mountain range which has a 30° slope, the border would be at a 15° slope inward from being perpendicular (to sea level) leaning in on A. [[Special:Contributions/141.101.77.144|141.101.77.144]] 04:51, 24 September 2021 (UTC)

Borders are usually vertical; what definition of "vertical", though? Some geodetic system? (Which one?) Local plumb line? Something else? [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 06:48, 24 September 2021 (UTC)

2363: Message Boards

2020-09-24T06:38:01Z

Sabik: Add the "new user" marker for JULZ in the transcripty

{{comic
| number = 2363
| date = September 23, 2020
| title = Message Boards
| image = message_boards.png
| titletext = (c) You can have a scooter when you pay for it yourself, and (d) if you can't learn to start a new thread rather than responding to an old one, you'll be banned. [thread locked by moderator]
}}

==Explanation==
{{incomplete|Created by Julian's kid in 2040, who wants a hover-scooter. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

The joke of this comic lies in the dates of the forum posts and the (presumed) relation between the posters.

The initial post was made in 2000 by NIN85 who was, at the time, a teenaged girl (likely 14-15 years old given her username ends in 85, implying she was born in 1985), complaining that her mother did not allow her to get a {{w|Vespa}}. Vespa is a brand of scooters and mopeds produced by the Italian manufacturer Piaggio. Most U.S. states require motorcycle licenses for any vehicle with an engine size over 50 cubic centimeters. Most Vespas are larger than this, although 49 CC models (classified as mopeds) do exist.

The reply was written in 2020 (twenty years later) by JULZ (or Julian), the son of the now-adult NIN85. "Julz" complains about his mother refusing to allow him to get an electric scooter, which doesn't require a license. He is implicitly pointing out the hypocrisy of his mother, as a 15-year-old, thinking that teenagers with scooters are perfectly reasonable, while as a 35 year old, being against the idea.

The humor derives partially from the fact that this isn't really hypocrisy: we expect teenaged viewpoints to evolve into mature adult viewpoints, and do not hold adults to promises made or beliefs held when they were teenagers. Humor also results from the unexpected situation of the child tracking down his mother's old forum post, and his mother still being active in the same niche forum 20 years later. She quickly responds to his comment, addressing him by his real name, which makes it clear they are related. She points out that they had already talked about it (presumably explaining why he is not allowed to get an electric scooter) and expressing her disbelief that he managed to find her original post on the message board.

In the title text, the parent is apparently a {{w|Internet_forum#Moderators|mod}} on that board now, or at least can quickly twist the ear of an actual mod. (It is unclear whether she ever got her scooter and perhaps became a different kind of {{w|Mod_(subculture)|Mod}}.) She threatens banning if the kid does not learn to post a new thread for stuff like this instead of dredging up dead threads from years ago, a common complaint on message boards. The act of 'reviving long-dead threads' is often described as "necromancy", or "necroing", and some subforums may actually encourage tagging onto existing but idle discussions (to add new/updated information) rather than repeatedly creating new threads (that end up rehashing or linking all old information).

This 'necro' does not seem to be particularly informative, however, except as a curiosity. It's possible the motivation to lock this thread is more about hiding her hypocrisy from other users on the board than for the usual reason of letting dead threads stay dead, but a locked thread is usually still readable. It could easily be found and read by old and new forum-goers alike. Even, if not lost entirely by then, by a son or daughter (or sentient AI child-entity) of Julz in yet another twenty years. And they may even be able to have the discussion unlocked just to append their own topical teenage complaints against Julian the parent.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[View of the "MopedPro" forum on a message board.]
::Forum Tab: '''''MopedPro Forum''''' (Top Left) | (4 tabs with illegible writing on them. None of them appear to be selected) (Top Right)
:NIN85 (posted December 5, 2000): So mad that my mom won't let me get a Vespa. I'm old enough for a moped license and they're really not that dangerous.
:JULZ [new user] (posted September 23, 2020): At least she's not stopping you from getting an electric scooter you don't even need a license for
:NIN85 (posted September 23, 2020): Okay, Julian, (A) you know we talked about this, and (B) how the heck did you find this thread

:Subtitle: I love that message boards are now old enough for this to happen.

{{comic discussion}}

[[Category:Social networking]]

Talk:2339: Pods vs Bubbles

2020-07-30T08:06:47Z

Sabik: A semi-serious bubble based on terminology differences

What's a "pod"? Incoherent comic. [[Special:Contributions/172.69.63.173|172.69.63.173]] 15:31, 29 July 2020 (UTC)

According to [https://www.nytimes.com/2020/06/09/parenting/coronavirus-pod-family.html this New York Times article], it has to do with families forming groups during quarantine.
"One idea that some families are considering — and that infectious disease epidemiologists think might be a smart way to balance mental health needs with physical safety — is to create quarantine “pods” or “bubbles,” in which two or three families agree to socialize with one another but no one else. In a pod, families hang out together, often without regard to social distancing — but outside of the pod, they follow recommended social distancing rules." --[[User:Borgendorf|Borgendorf]] ([[User talk:Borgendorf|talk]]) 16:01, 29 July 2020 (UTC)

From context, especially the reference to Canada, I take it that Pod is the US term (more predominantly) for the situation that Canada may (and UK does) mostly call a Bubble. It may be a good sign that the person who wants to Bubble/Pod comes from the place where the situation is worse (US v Canada, at least). In the UK we used (and still do) the term Key Workers for what others may call Essential Workers (asked to continue to work, even in lock-down, and ideally take more care outside of work to prevent forcing them into deeper isolation), which was especially funny when applied to a locksmith on contract with the health service... [[Special:Contributions/162.158.154.131|162.158.154.131]] 16:22, 29 July 2020 (UTC)

I don't think this is a US-Canada thing. I'm an American (Californian more specifically) and I've heard both terms commonly. [[Special:Contributions/172.68.142.99|172.68.142.99]] 19:50, 29 July 2020 (UTC)

I think we should start a category of comics in which Randall/Cueball interacts with (or imagines interacting with) his past self or someone from the past -- some of them are literally [[:Category:Time travel|time travel]] comics (e.g. [[2280: 2010 and 2020]] and [[2220: Imagine Going Back in Time]]), but others are not, at least not directly (like this one, or [[2302: 2020 Google Trends]]). Some ideas for the category name: "Retrospectives", "Comics featuring perspectives from the past", "Comics imagining what the past might think of the present"...I'm not wild about any of these; does anyone else have other suggestions? --[[User:NotaBene|NotaBene]] ([[User talk:NotaBene|talk]]) 18:15, 29 July 2020 (UTC)

I swear I thought this was about Tide Pods or such. I just figured that Canada products called them "bubbles". [[Special:Contributions/108.162.210.162|108.162.210.162]] 05:20, 30 July 2020 (UTC)

When the second wave hit Victoria (Australia), and a border closure with NSW was being considered/announced, there were jokes that (as a [[wikipedia:Shibboleth|shibboleth]]) travellers will be asked to identify a food item and denied entry if they call it a "potato cake" (the food is called "potato scallop" or just "scallop" in most of NSW). [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 08:06, 30 July 2020 (UTC)

Talk:2206: Mavis Beacon

2019-09-24T05:07:43Z

Sabik: Unicode numbers 𝟙𝟚𝟛𝟜𝟝𝟞𝟟𝟠𝟡𝟘

== So the # key, then? ==

Shifted or not? The implication is that it is, since that's where ‘~’ is. [[Special:Contributions/141.101.99.41|141.101.99.41]] 18:44, 23 September 2019 (UTC)
: On a typical German QWERTZ layout keyboard, the tilde key '~' can/must be entered via AltGr++; alternatively, Ctrl+Alt++ should work when there is no AltGr key. On certain "dead key" keyboard layouts, there even is no single and direct '~' key: To type a tilde, one would have to press AltGr++ followed directly by a space or to double-tap + while holding AltGr. This would mean even more complicated or pretty much impossible key combinations that would be needed to be pressed at the same time. However, holding AltGr or Ctrl+Alt to try and type a tilde would probably cancel out the "single" Alt key necessary for the comic's secret key code. So, once you've managed to type a tilde, it likely wouldn't count any more for the key combo, making it impossible to type this key combination on such keyboard. --[[User:Passerby|Passerby]] ([[User talk:Passerby|talk]]) 19:26, 23 September 2019 (UTC)
: I've seen many programs provide hotkey instructions calling the grave key the tilde key due to the difficulty of differentiating between the grave key and the apostrophe key. So I'd assume no shifting is required. [[User:CJB42|CJB42]] ([[User talk:CJB42|talk]]) 01:51, 24 September 2019 (UTC)

The link from Friday's comic to this new one is missing. [[User:N0lqu|-boB]] ([[User talk:N0lqu|talk]]) 19:21, 23 September 2019 (UTC)
: This page was created by the bot only a short while ago. I may be wrong, but I think those links will be set automagically by such bot at some point after the creation of this page. --[[User:Passerby|Passerby]] ([[User talk:Passerby|talk]]) 19:31, 23 September 2019 (UTC)

== Unicode ==

Presumably a lot of this could be achieved with Unicode; any advances on 𝟙𝟚𝟛𝟜𝟝𝟞𝟟𝟠𝟡𝟘? [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 05:07, 24 September 2019 (UTC)

== Trochees ==
To tie this to a recurring theme in Mr. Munroe's comics... "Mavis Beacon Teaches Typing - Heroes on the half shell." [[User:Ryanker|Ryanker]] ([[User talk:Ryanker|talk]]) 20:14, 23 September 2019 (UTC)

== Other ==
Currently, the button on Comic #2205 to go to this comic is missing - someone with more technical expertise than me, please fix this [[Special:Contributions/172.69.22.134|172.69.22.134]] 21:07, 23 September 2019 (UTC)

Fixed it - to do it, go to https://www.explainxkcd.com/wiki/index.php?title=2205:_Types_of_Approximation&action=Purge , this works for any page if you change "2205:_Types_of_Approximation" to what it should be.

Talk:2100: Models of the Atom

2019-01-18T10:36:51Z

Sabik: What is 173?

No mention of the Platonic solid model? [[User:DanielLC|DanielLC]] ([[User talk:DanielLC|talk]]) 05:56, 18 January 2019 (UTC)

Not yet. My favorite of those 5 is the double cube, AKA the Octahedron. [[User:Haph|Haph]] ([[User talk:Haph|talk]]) 06:35, 18 January 2019 (UTC)

:My good sir DanielLC: I presume that Randall neglected to mention it because the first evidence-based atom theory didn't come until 1810 and John Dalton. The atom theories of the ancient Greeks were mostly philosophical posturing, in my opinion.

:We seem to be missing the [[https://en.wikipedia.org/wiki/Acorn_Atom| Acorm Atom]] as well. [[User:Kazzie|Kazzie]] ([[User talk:Kazzie|talk]]) 10:16, 18 January 2019 (UTC)

According to [[https://www.ast.cam.ac.uk/~trentham/cosmology/lec6.pdf|cosmology lecture notes by the astronomer Neil Trentham]], mass in the universe ist 75% H (mostly 1p+0n=1) and 25% He (mostly 2p+2n=4). As He is 4 times as heavy and 3 times as seldom, there is 12 times more H than He => The ratio n/p is 1/7.
We can assume that in the 538 model the statistics was done on atoms comprising few Hydrogene, e.g. only the earth's mantle. In heavier elements the ratio n/p > 1. Sebastian --[[Special:Contributions/172.68.110.70|172.68.110.70]] 07:39, 18 January 2019 (UTC)

What are the numbers? Is 173 an error for 137, the fine structure constant? [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 10:36, 18 January 2019 (UTC)

Talk:2100: Models of the Atom

2019-01-18T10:36:46Z

Sabik: What is 173?

2053: Incoming Calls

2018-10-02T12:00:44Z

Sabik: /* Explanation */ Add alternative explanation of title text tactic

{{comic
| number = 2053
| date = October 1, 2018
| title = Incoming Calls
| image = incoming_calls.png
| titletext = I wonder if that friendly lady ever fixed the problem she was having with her headset.
}}

==Explanation==
{{incomplete|Please edit the explanation below and only mention here why it isn't complete. Do NOT delete this tag too soon.}}
This comic shows a graph of incoming phone calls over time to [[Randall]] since he was younger than six years. The graph doesn't show the absolute numbers but the proportion of callers. Because it's safe to assume that calls from his family didn't decrease over the years, other calls just increased over time and this graph can be misunderstood because the number of calls in the recent years are probably much higher than in 1990. This leads to Randall's second header line when he states that he "finally stopped picking up for unknown numbers", which is still roughly the same fraction but the amount is much more today.

Wrong numbers used to be a small but significant portion of the phone calls that Randall received, and remained fairly steady until the late 1990s, when they began a gradual and accelerating decline, eventually tapering off to nearly none in 2015. This is likely due to the rise of cellphones and programmable land-line phones, which contain their own address books and only require the caller to enter the number once, greatly reducing the chances of accidentally entering a wrong number in general and eliminating the possibility entirely for anyone with whom you have taken the time to save their number.

It is not clear exactly why appointment reminders and misc calls have steadily increased with time, though it is possible that as Randall grows older, his responsibilities, and thus the number of appointments and legitimate businesses who need to contact him, have grown.

The proportion of friends who call Randall rapidly increased in the 1990s and began to overtake family, probably because he has gained friends over time and because as they grew up they were more likely to own their own phone, and starting in the 2000s, their own cellphones. Over time, Randall's friends and family have been less likely to make phone calls to him, likely due to the use of text messages and other messaging apps. Additionally, although there was a large percentage of phone calls from legal {{w|Telemarketing|telemarketers}} in the 1990s, this percentage has significantly dropped, most likely due to the creation of the {{w|National Do Not Call Registry}}, which allows individuals and families in the United States to register phone numbers that are exempt from telemarketers. Instead, there has been a rise in phone calls from {{w|Phone fraud|scammers}} and political advertisements. Even if a phone number is registered on the National Do Not Call Registry, they may still receive phone calls from political organizations. It is implied that the latter two groups have caused Randall to stop answering phone calls from unknown numbers.

The title text refers to a common scamming tactic in which a {{w|Robocall|robocaller}}, typically one named "Emily," will claim to be having trouble with their headset and say "Can you hear me now?" The trick is either to keep you on the line while taking a second or two to connect you to a real person to get scammed, or to get a recording of you saying "yes" for potential fraudulent use (or both).

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[A line graph shows the portions of phone calls by type over time beginning slightly before 1990 until today.]
:'''Incoming personal calls over time'''
:or: why I finally stopped picking up for unknown numbers

:[The x-axis is labeled with years beginning at 1990 in five year segments up to NOW (2018). The y-axis shows a relative distribution of callers.]
:[The calls are (from top to down):]
:Appointment reminders, misc. (small growing all over time)
:Family (larger in the beginning, constant with some fluctuations since 2000)
:Friends (growing from 1995 to 2005, then decreasing but intersected with "that one friend who hates texting", after that decreasing)
:Legal telemarketers (peak in the beginning, decreasing over time)
:Auto insurance scammers (a big peak between 2005 and 2012)
:Other scammers (beginning in 2010, replacing the auto insurance, increasing until today)
:Political (starting in 2002 and increasing since then)
:Wrong numbers (constant up to 2000 and then decreasing to nearly zero today)

{{comic discussion}}

[[Category:Comics featuring Randall Munroe]]
[[Category:Line graphs]]
[[Category:Timelines]]

Talk:1925: Self-Driving Car Milestones

2017-12-07T13:22:05Z

Sabik: An empty car wandering the highways, forgotten, lost

This page is, without offense to the creator, a mess. We're gonna need a table for this. [[Special:Contributions/172.68.47.78|172.68.47.78]] 19:14, 6 December 2017 (UTC)
* Or at least a list. I have created one, but it could use fleshing out.[[User:WingedCat|WingedCat]] ([[User talk:WingedCat|talk]]) 19:55, 6 December 2017 (UTC)
::List is fine. You don't need a table for everything - especially if this table had only one or two columns...
: none taken, it's my first time (I only wrote the first three points from a blank page) [[Special:Contributions/162.158.111.61|162.158.111.61]] 09:08, 7 December 2017 (UTC)

I'm going to go with a [citation needed] on that "sex in a self-driving has probably already happened." Are there stats suggesting the amount of coitus per vehicle in the relevant counties?

"This a joke about Boolean satisfiability, as evaluating an arbitrarily complex bumper sticker and determining whether to honk is NP-complete." What? Determining whether to honk has nothing to do with the satisfiability problem; this is more of a joke about getting a computer to evaluate the truth of Boolean expressions that it may have no information about. [[User:Checkmate|Checkmate]] ([[User talk:Checkmate|talk]]) 22:07, 6 December 2017 (UTC)Checkmate

I believe the "Autonomous canyon jumping" is related to the self-loathing; a self-loathing is likely to autonomously jump off a cliff. [[Special:Contributions/108.162.212.179|108.162.212.179]] 22:30, 6 December 2017 (UTC)

"As of 2017, self-driving s require a human to be able to take over just in case, but any such trip where the human never actually took control would qualify for this milestone."
I seems like not all places require a human backup driver: https://www.theverge.com/2017/11/7/16615290/waymo-self-driving-safety-driver-chandler-autonomous [[Special:Contributions/172.69.22.146|172.69.22.146]] 23:19, 6 December 2017 (UTC)

Time to start printing "Honk if this statement evaluates as 'do not honk!'" bumper stickers! [[Special:Contributions/162.158.63.28|162.158.63.28]] 01:24, 7 December 2017 (UTC)

Is this related to the Vsauce Mind Field video about self-driving s and the trolley problem the literally released today, or is it just a weird coincidence?[[Special:Contributions/162.158.74.225|162.158.74.225]] 05:13, 7 December 2017 (UTC)

The likelihood of trolley-like problems is no lower for an autonomous car than a human-driven one, since it depends on external factors. It might be true that if a significant number of the ''other'' cars on the road were replaced with self-driving ones, that would reduce the occurrence of conflicts, and therefore the likelihood and severity of these problems would be lower, but it would be lower for self-driven and human-driven cars alike. The real issue with such debates is that they tend to make a false assumption that existing human drivers are good at solving these problems, when the whole thrust of these thought experiments is to demonstrate that there are no generally accepted solutions to these problems.[[Special:Contributions/141.101.104.239|141.101.104.239]] 09:33, 7 December 2017 (UTC)

"Given the nature of human sexuality, it is possible this has already happened, but there has not been a public documentation of this milestone."
Rule 34 applies. --[[Special:Contributions/162.158.89.133|162.158.89.133]] 12:44, 7 December 2017 (UTC)

"An empty car wandering the highways" - that doesn't seem so ridiculous; a car costs what, $9000/year? That's like an EC2 instance and not even the biggest one. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 13:22, 7 December 2017 (UTC)

Talk:1923: Felsius

2017-12-03T06:42:12Z

Sabik: Switched symbol for "degree Felsius" to °⋲

Thanks who, at the same time as I, wrote the better explanation with formulae; you're welcome for the table (which, for my first attempt at a MediaWiki table, and in a big hurry to be first*, I think came out all right). ((*Go ahead and edit at will!)) --'''BigMal''' // [[Special:Contributions/108.162.216.184|108.162.216.184]] 16:44, 1 December 2017 (UTC)

Seems like this is awfully relevant: https://xkcd.com/927/ -- '''Derek Antrican''' [[Special:Contributions/108.162.246.23|108.162.246.23]] 16:54, 1 December 2017 (UTC)

You can't write formulas like that! °C is degree(s) Celsius, not the value of some temperature as measured in degrees Celsius. You should write something like [°C] or °C-1 instead (if we treat °C as an affine function mapping dimensionless values to temperatures). Or you can be explicit and say something like "x°F = ((x − 32) * 5 / 9)°C". --[[Special:Contributions/172.68.54.22|172.68.54.22]] 19:59, 1 December 2017 (UTC)

Fahrenheit contribution to the name is disproportionately small for an average of two scales. It should have been at least Falsius, with added punniness, or Fahlsius, to be more unique. -- '''Average Alex'''

: It should be ‘Fahlsius’, or even ‘Fählsius’, but notice that the pronunciation will still be more or less like ‘Felsius’ and not like ‘Fall-sius’ (for the same reason that ‘Fahrenheit’ or ‘Fährenheit’ is pronounced more or less like ‘Fair-enheit’ and not like ‘Far-enheit’. —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 04:58, 3 December 2017 (UTC)

I'm obliged to share https://www.youtube.com/watch?v=227Hdz8VFKo. As a pedant, I have to point out that water's melting and boiling point aren't quite at 0 °C and 100 °C (and that Celsius originally had it backwards). And I *do* like "Falsius". [[User:Fluppeteer|Fluppeteer]] ([[User talk:Fluppeteer|talk]]) 21:19, 1 December 2017 (UTC)

Watchout for Felsius/Celsius or Felsius/Fahrenheit hybrids: https://xkcd.com/419/ [[User:WhiteDragon|WhiteDragon]] ([[User talk:WhiteDragon|talk]]) 22:20, 1 December 2017 (UTC)

What is an "epislon"?
[[Special:Contributions/162.158.88.170|162.158.88.170]] 23:02, 1 December 2017 (UTC)

: A Greek letter; follow the link where the word first appears in the explanation. —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 04:58, 3 December 2017 (UTC)

I think the Ukranian Ye (Є) would be closer, visually speaking.[[Special:Contributions/162.158.186.42|162.158.186.42]] 23:40, 1 December 2017 (UTC)
: Or the mathematical symbol ⋲ (ELEMENT OF WITH LONG HORIZONTAL STROKE) or C̶ (LATIN CAPITAL LETTER C + COMBINING LONG STROKE OVERLAY)? Or ℃̶ (DEGREE CELSIUS + COMBINING LONG STROKE OVERLAY)? [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 11:36, 2 December 2017 (UTC)
:: Yes, ELEMENT OF WITH LONG HORIZONTAL STROKE seems exactly right (not only by look, but also since ELEMENT OF is basically a lunate Epsilon already and changing the HORIZONTAL STROKE so that it is LONG is precisely the modification WITH which it needs to be equipped), and I think that we should switch to this immediately! —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 04:58, 3 December 2017 (UTC)
::: Done. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 06:42, 3 December 2017 (UTC)

Apparantly someone needs to be taught about the Rømer scale that is the ancestor of both Celcius and Fahrenhet. It has fixed constants for all three of water boiling, freezing and the temperature of brine.[[Special:Contributions/162.158.202.226|162.158.202.226]] 23:06, 2 December 2017 (UTC)

I remove the reference to ammonium chloride from the temperature table because, while it is cool (both figuratively and literally), it's also obsolete: in the modern Fahrenheit scale, this happens at 4°F, not at 0°F. (See the table at {{w|Frigorific mixture}}.) —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 04:58, 3 December 2017 (UTC)

If the creator of the website that was inspired by the comic created one that was based on SE Asian countries, I would like to know the felsius of that. I am curious as heck.Boeing-787lover 06:33, 3 December 2017 (UTC)

1923: Felsius

2017-12-03T06:40:45Z

Sabik: Switch symbol for "degree Felsius" to °⋲ (with corresponding tweak to the text)

{{comic
| number = 1923
| date = December 1, 2017
| title = Felsius
| image = felsius.png
| titletext = The symbol for degrees Felsius is an average of the Euro symbol (€) and the Greek lunate epsilon (ϵ).
}}

==Explanation==
{{incomplete|Is there anything to add?}}

Just like in [[1292: Pi vs. Tau]], [[Randall]] tries to unify two measurement systems by averaging both values, assumably with little success.

There are several {{w|Scale_of_temperature|temperature scales}} actively used in different parts of the world of for different purposes, including {{w|Celsius}} and {{w|Fahrenheit}}, but e.g. also {{w|Kelvin}} and {{w|Rankine_scale|Rankine}}.

The debate on whether to use Fahrenheit or Celsius is, just like the one between {{w|Imperial_units|imperial}} and {{w|Metric system|metric}} units, one that is mostly restricted to the US. While Fahrenheit is a widely used temperature scale in the US, most other countries have already switched from Fahrenheit to Celsius or have always used Celsius. In scientific circles, even in the US, only Celsius (and Kelvin) are used.

The conversion factors between Celsius and Fahrenheit are:
:°C = (°F − 32) × 5 / 9
:°F = °C × 9 / 5 + 32

which indeed make the average value of °C and °F:
:°⋲ = °C × 7 / 5 + 16 = (°F × 7 - 80) / 9

[[Randall]] choose to name his new unit of temperature Felsius (a {{w|portmanteau}} of Fahrenheit and Celsius).

The title text states that the symbol he chose to represent this unit also is the average of two other symbols. Visually, it is assumed to be a combination of Celsius and Fahrenheit (a C with a crossbar), but it is actually the unrelated symbols for the {{w|Euro sign|euro}} (€) and the Greek lunate {{w|epsilon}} (ϵ). Randall's symbol has a single crossbar, like the Greek lunate epsilon, but the crossbar continues to the left, like the Euro symbol.

{|class="wikitable"
!Symbol!!Number of crossbars!!Length of crossbar(s)
|-
||Euro||2||Long
|-
||Epsilon||1||Short
|-
||Felsius||1||Long
|-
||[not used]||2||Short
|}

In doing all this, Randall has fallen into the trap of creating a new temperature scale/standard: see [[927|927: Standards]].

Randall has also compared Celsius and Fahrenheit scales earlier in [[1643: Degrees]].

This is an example of {{w|Argument_to_moderation|Argument to Moderation}}, also known as the false middle point fallacy. A famous use of this fallacy is in the Bible, the {{w|Judgment_of_Solomon|Judgment of Solomon}}. The true mother of a disputed baby is discovered by proposing the "compromise" of cutting the baby in half. Perhaps Randall has a similar strategy in proposing Felsius, an absurd compromise, in order to discover the "true" temperature scale.

=== Table of Given Conversions & Additional ===
{| class="wikitable"
!°⋲!!°C!!°F!!Note
|-
| style="text-align:right;" |156.0
| style="text-align:right;" |100.0
| style="text-align:right;" |212.0
||Water boils at sea level (1 atmosphere)
|-
| style="text-align:right;" |91.6
| style="text-align:right;" |54.0
| style="text-align:right;" |129.2
||World heat record (per [https://en.wikipedia.org/wiki/Highest_temperature_recorded_on_Earth Wikipedia])
|-
| style="text-align:right;" |67.8
| style="text-align:right;" |37.0
| style="text-align:right;" |98.6
||Body temperature (accepted average)
|-
| style="text-align:right;" |46.8
| style="text-align:right;" |22.0
| style="text-align:right;" |71.6
||Room temperature (maximum per [https://ahdictionary.com/word/search.html?q=room+temperature American Heritage Dictionary])
|-
| style="text-align:right;" |16.0
| style="text-align:right;" |0.0
| style="text-align:right;" |32.0
||Water freezes at sea level (1 atmosphere); 0°C reference
|-
| style="text-align:right;" |0.0
| style="text-align:right;" |−11.4
| style="text-align:right;" |11.4
||0°⋲ reference
|-
| style="text-align:right;" |−8.9
| style="text-align:right;" |−17.8
| style="text-align:right;" |0.0
||0°F reference
|-
| style="text-align:right;" |−40.0
| style="text-align:right;" |−40.0
| style="text-align:right;" |−40.0
||Equivalence point (exactly −40°)
|-
| style="text-align:right;" |−366.4
| style="text-align:right;" |−273.2
| style="text-align:right;" |−459.7
||Absolute zero (exactly −273.15°C or −459.67°F)
|}

==Transcript==
:[A thermometer is shown where the temperature is indicated, with a red column of liquid, to be just above room temperature. This can be seen from the five labels belonging to five lines pointing at the scale. None of these coincide with the 14 ticks on the actual scale for the thermometer. Below the last label is the formula for calculating the temperature on this scale.]
:92°⋲ world heat record
:68°⋲ body temperature
:47°⋲ room temperature
:16°⋲ water freezes
:–9°⋲ 0°F
:°⋲=7×°C/5+16=(7×°F–80)/9

:[Caption below the panel:]
:Since the Celsius vs Fahrenheit debate has proven surprisingly hard to resolve, as a compromise I've started using Felsius (°⋲), the average of the two.

==Implementations==
An implementation of Felsius is available at [http://www.weatherinfelsius.us Weather In Felsius], using a location based on user's IP address and accepting US ZIP codes.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Portmanteau]]
[[Category:Math]]
[[Category:Physics]]
[[Category:Compromise]]

Talk:1923: Felsius

2017-12-02T11:36:32Z

Sabik: Possible Unicode representations of the Felsius symbol

Talk:1559: Driving

2015-08-04T06:13:18Z

Sabik: "border" could be state border.

They're probably in California, seeing as that's the only place self-driving cars are actually on the road. [[User:Wmss|Wmss]] ([[User talk:Wmss|talk]]) 09:46, 3 August 2015 (UTC)

If there are self-driving cars, what about self-filling cars? So these cars are able to make long distances without the driver's interaction. Maybe he is sleeping. [[User:GeorgDerReisende|GeorgDerReisende]] ([[User talk:GeorgDerReisende|talk]]) 10:47, 3 August 2015 (UTC)
: Yeah, for some reason that does not exist yet -- the self-driving car on the other hand DOES exit and I can see them driving down my street every day [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:07, 4 August 2015 (UTC)

Should've used hitchBOT instead of a rock. [[Special:Contributions/108.162.216.82|108.162.216.82]] 12:46, 3 August 2015 (UTC)

Could this have been a semi-tribute? Showing how some malicious people will abuse technology that is programmed to be too trusting? [[Special:Contributions/108.162.216.138|108.162.216.138]] 20:56, 3 August 2015 (UTC)
: Could you explain with an example [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:07, 4 August 2015 (UTC)

I disagree with the part of the explanation that claims that the comic must take place in the continental US. The title text doesn't specify "exactly two" border crossings; it merely implies that there is more than one. That could be anywhere in mainland (or attached-to-the-mainland-by-bridge) North America, north of the Darien Gap, except for most of Canada (from most of the population centers of Ontario, Google Maps wants to route through Michigan, for a total of three border crossings). [[Special:Contributions/108.162.221.149|108.162.221.149]] 14:18, 3 August 2015 (UTC)
:Correct. It "implies" more than one, but doesn't require it. Only that there be at least one. So they could be in Canada. Essentially anywhere on the continent (or an island connected by bridge to the mainland (e.g., Florida Keys)) north of the Darien Gap but outside Alaska. - Equinox [[Special:Contributions/108.162.238.172|108.162.238.172]] 23:15, 3 August 2015 (UTC)

It is likely that the car's owner can locate it via the Internet, via an app and location logic provided by the car's manufacturer. E.g., OnStar. {{unsigned ip|108.162.216.157}}

"At the time of the release of this comic there were no places where these cars could be used privately." That is not true, as there are no restrictions on vehicle use on private property. --[[Special:Contributions/108.162.212.7|108.162.212.7]] 16:35, 3 August 2015 (UTC)
: You are correct, and I have fixed that -- the true statement is that they are not for sale to private individuals [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:03, 4 August 2015 (UTC)

The only US state that both borders Canada and permits self-driving cards is Michigan. Assuming that the logic in self-driving cars prevents them from driving on streets where they are not legal, the conversation would have to take place in that state (but then again, wouldn't the car know that it is not allowed to drive in Alaska?) [[Special:Contributions/162.158.92.64|162.158.92.64]] 19:38, 3 August 2015 (UTC)
:Maybe it's exactly a matter of what knowledge the car has. It ''could'' be linked up to something proprietry, or possibly a Cortana information-engine, to control a virtual "GPS fence", based on current legal and possibly licence-based limits. I'll bet it can be reprogrammed to ignore/extend such limits, though. (Which is why I'm dubious about the idea of 'hard limiting' flying drones from entering restricted airspace. A little hardware/software/firmware hacking should be simple enough for anyone who needs to get around such limits.)
:I can also imagine the following conversation: "How far does your car's self-driving system let you go on automatic?" "I'll ask her..."(/Alaska...) [[Special:Contributions/141.101.98.188|141.101.98.188]] 00:33, 4 August 2015 (UTC)
:Yes the car would know that it was not permitted to drive in Alaska, however that would not prevent it from setting of with that destination in mind assuming that the person would take over control and entering manual driving in places where automatic were not permitted. [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]]) 01:03, 4 August 2015 (UTC)
::In that case, the "border" in the title text could be a state border... [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 06:13, 4 August 2015 (UTC)

1547: Solar System Questions

2015-07-07T13:17:47Z

Sabik: /* Explanation */ plural "lunar maria"

{{comic
| number = 1547
| date = July 6, 2015
| title = Solar System Questions
| image = solar_system_questions.png
| titletext = My country's World Cup win was exciting and all, but c'mon, what if the players wore nylon wings and COULD LITERALLY FLY?
}}

==Explanation==
{{incomplete|1) Explain "in the wrong places" re: Io's volcanoes. 2) Explanation needed for why "ice spikes" on Europa are hypothesized.}}

This comic is a list of questions which [[Randall]] has about the Solar System, which at first glance may appear to be things that Randall would like to learn about.
In actual fact most of the questions have not been satisfactorily answered or proven by anyone in the {{w|List_of_unsolved_problems_in_physics#Astronomy_and_astrophysics|scientific community}}.

{| class="wikitable"
|-
! Question given
! Answer given by Randall (in Red)
! Comments
|-
| Why is the the Moon so blotchy?
| Lava
| The {{w|Moon}} is in synchronous rotation with Earth, which means that we always can see only one half of the surface of the Moon. And on that side we can see large {{w|lunar maria}} formed by lava from big volcanoes. This surface is very different to all other celestial bodies we know in our Solar system. The double "the the" could be a Randallism — intended or unintended.
|-
| Why are all the blotches on the near side?
| ...
| The nearside of the Moon is dominated by the blotchy 'seas' or maria, the far side by craters. {{w|Far_side_of_the_Moon#Differences|Several explanations}} for this have been proposed, including an overabundance of impacts obliterating the blotches on the more exposed far side, different compositions of heat-producing elements, large collisions, or heat produced by the still-cooling Earth.
|-
| Did Mars have seas?
| Yes (briefly?)
| Recent explorations have confirmed there was once standing (and also flowing) water on {{w|Mars}}. Many rovers and orbiters on Mars give us the evidence on this early development of that planet, but it is still unknown how long such conditions existed in its history.
|-
| Was there life on Mars?
| ...
| One of the big mysteries, not yet answered.
|-
| What's Titan like?
| Cold, yellow, lakes + rivers (methane)
| The {{w|Cassini–Huygens}} mission confirmed the presence of {{w|Lakes_of_Titan|lakes and rivers}} on {{w|Titan (moon)|Titan}}. The {{w|Huygens_(spacecraft)#Findings|Huygens}} lander itself returned some very yellow images of a dry lake bed from Titan's surface.
|-
| What was Earth like during the Hadean?
| ...
| The {{w|Hadean}} was the first geologic era on earth, the planet had just formed and not much is known of that period of Earth. But since it was the time when Earth was formed it was mainly very hot with extreme volcanic activity, with the entire surface melted. This is why the era is named after {{w|Hades}} the ancient Greek god of the underworld.
|-
| Is the Oort Cloud a real thing?
| ...
| The {{w|Oort Cloud}} is a theoretical spherical cloud of icy planetesimal, maybe dust, and also larger objects at a distance of up to around 100,000 {{w|Astronomical units|AU}} to our Sun. We can see similar clouds at other stars, but there is still no evidence that this cloud exists in our Solar System.
|-
| Why is the Sun's corona so hot?
| Something about magnets?
| The {{w|corona}} of the sun is hotter than it theoretically should be. The looping magnetic fields in this area could be responsible.
|-
| What are comets like?
| Precipitous
| The {{w|Philae (spacecraft)|Philae lander}} is next to a cliff...
|-
| Where's Philae, exactly?
| ...
| ...but we're not sure ''which'' cliff.
|-
| What's Pluto like?
| rowspan="2" | [Soon!]
| rowspan="2" | The probe {{w|New Horizons}} may be about to answer both of these questions as it will reach it's closest approach to both {{w|Pluto}} and {{w|Charon (moon)|Charon}} just eight days after the release of this comic.
|-
| What's Charon like?
|-
| Why don't we have in-between-sized planets?
| ...
| There is a size-gap between the rocky {{w|terrestrial planets}} up to Earth size and the {{w|gas giants}} very much larger than Earth in our Solar System.
There are many known {{w|exoplanets}} (planets in other solar systems) filling in the range between our rocky planets and our gas giants, known as [https://upload.wikimedia.org/wikipedia/commons/2/2c/Exoplanet_Mass-Radius_Scatter_Super-Earth.png Super-Earths]
|-
| What's Ceres like?
| [Working on it!]
| The {{w|Dawn (spacecraft)|Dawn probe}} is currently exploring the {{w|dwarf planet}} {{w|Ceres (dwarf planet)|Ceres}} and reveals unseen surface features.
|-
| Why is Europa so weird-looking and pretty?
| Ice over a water ocean
| {{w|Europa (moon)|Europa}} is a moon of {{w|Jupiter}} and the surface is basically thick pack ice covered in {{w|lineae}}.
|-
| Why is Io so weird-looking?
| Sulfur volcanoes (? in the wrong places?)
| The moon {{w|Io (moon)|Io}} is also orbiting Jupiter and is close enough that {{w|tidal forces}} make it the most volcanic object in the solar system. The moon is mainly yellow but there a several other colors on the surface, for instance spots and streaks of bright red color that comes from {{w|sulfur}} which is ejected by the volcanoes.
|-
| Why are so many Kuiper Belt objects red?
| ...
| Many objects in the {{w|Kuiper Belt}} have a reddish hue. A possible explanation is that they are [http://www.space.com/9418-icy-red-objects-solar-system-edge-point-life-building-blocks.html| covered in organic molecules] formed by the irradiation of their surface ices. The New Horizons probe might also shed light on this.
|-
| What are those spots on Ceres?
| ...
| The Dawn probe found some mysterious spots on the Ceres. These [http://photojournal.jpl.nasa.gov/jpeg/PIA19568.jpg white spots] are still not understood, but the mission is still running and we may figure out the source of the glowing white features.
|-
| What's in the seas under Europa's ice?
| ...
| The European {{w|ESA}} selected the mission {{w|Jupiter Icy Moon Explorer|Jupiter Icy Moon Explorer (JUICE)}} to Jupiter. The moon Europa is one target for that mission. But we have to wait, its launch target is 2022 and the arrival at Jupiter is planned for 2030. But that's not uncommon for missions like this, New Horizons or {{w|Rosetta (spacecraft)|Rosetta}} did also travel approx. ten years to reach their target. And before such a mission can start many preparations have to be done.
|-
| Which of the other moons have seas?
| Several
| Depending on the definition of 'sea', other less obviously 'frozen water world' moons such as {{w|Ganymede (moon)|Ganymede}} may have {{w|Ganymede (moon)#Subsurface oceans|subsurface}} [http://www.newscientist.com/article/dn27151-aurora-reveals-jupiter-moons-secret-subsurface-sea.html oceans] of liquid water or other substance liquid at the relevant temperature.
|-
| What are the big white things in Titan's Lakes?
| ...
| {{w|Lakes of Titan}}
|-
| What do Jupiter's clouds look like up close?
| ...
|
|-
| What's all that red stuff in the Great Red Spot?
| ...
| {{w|Great Red Spot}}
|-
| What's pushing the Pioneer Probes?
| Heat from the RTG
| Discussed as the {{w|Pioneer anomaly}}. RTG stands for {{w|Radioisotope Thermoelectric Generator}}.
|-
| What pushes spacecraft slightly during flybys?
| ...
| Several spacecraft experienced unexplained speed increases during Earth flybys. This is called the {{w|flyby anomaly}}.
|-
| Where are all the Sun's Neutrinos?
| Oscillating
| {{w|Solar neutrino problem}}
|-
| Why is there so much air on Titan?
| ...
| Titan has an atmospheric pressure 1.45 times that of Earth, but 1/7th of the surface gravity (that's less than Earth's own, practically airless, Moon). Hence the confusion! In fact, Titan actually has almost 20% more atmosphere (by mass) than Earth, and ''seven times'' more atmosphere across a given surface area!
Less influence from the more distant Sun probably helps retain more of the atmosphere's gasses (mostly nitrogen), and {{w|cryovolcanoes}} may replenish the methane fraction (which should by now have ''all'' been converted into the other hydrocarbons present) from subsurface reservoirs. But further studies are required to properly answer this question.
|-
| Why does the Kuiper Belt Stop?
| ...
| A reference to the {{w|Kuiper Cliff}}.
|-
| Why is Iapetus weird-colored?
| ...
| {{w|Iapetus (moon)|Iapetus}} is a moon of {{w|Saturn}} and has a white side and a dark side.
|-
| Why does Iapetus have a belt?
| ...
| Iapetus has a 13 km high ridge around most of the equator, and a number of 10 km high mountains where the ridge is interrupted.
|-
| What's the deal with Miranda?
| ...
| {{w|Miranda_(moon)|Miranda}} is the smallest of {{w|Uranus}}' five round satellites, and it's {{w|Verona Rupes|a bit rough around the edges}} and also has an unusually high orbital inclination that is difficult to explain. Also possibly a [[Firefly|''Firefly'' reference]] since {{w|List of Firefly planets and moons#Miranda|Miranda}} is also the name of a planet in {{w|Serenity (film)|''Serenity''}}, a film basedion the {{w|Firefly (TV series)|''Firefly''}} TV series.
|-
| Did Uranus and Neptune change places?
| ...
| The {{w|Nice model}} is a theory of how our solar system formed, which suggested the possibility of Uranus and {{w|Neptune}} having swapped places before reaching their current positions. Work by Professor S. Desch [http://dusty.la.asu.edu/~desch/publications/2007/Desch2007.pdf also came to this result].
|-
| Did the Late Heavy Bombardment happen?
| ...
| {{w|Late Heavy Bombardment}}
|-
| Did life start before it?
| ...
| For some speculation on this topic, see [http://www.livescience.com/5426-life-survived-earth-early-bombardment.html].
|-
| Is Europa covered in Ice Spikes?
| ...
|Dr Daniel Hobley has put forward a [theory http://www.bbc.co.uk/news/science-environment-21341176] that Jupiter's icy moon, {{w|Europa (moon)|Europa}}, has the right conditions to form ice spikes called {{w|penitentes}} of up to 10m in height.
|-
| Why haven't we built a big inflatable Extreme Sports Complex on The Moon?
| ...
| See, e.g., ''{{w|The Menace From Earth}}'', a 1957 short story by Robert Heinlein.
|}

The title text refers to the {{w|2015 FIFA Women's World Cup}} which was won by USA a day before. The nylon wings and flying may be a reference to two passages from 3001: The Final Odyssey, one where Frank Poole tries out various wings while in an extremely low gravity environment, and one where he remarks while watching Swan Lake that Tchaikovsky could never have imagined a performance where the dancers were actually flying (due to aforementioned low gravity). This is also a reference to the last point on the list, because if we had such a stadium on the moon, maybe it would be possible to use such wings to make very long floating leaps.

==Transcript==
:'''Questions I have'''
:'''about the solar system'''
:(some answered)

:{| class="wikitable" style="border: 0px;"
|-
| style="border: 0px; text-align: right" | Why is the the Moon so blotchy?
| style="border: 0px; color:red;" | Lava
|-
| style="border: 0px; text-align: right" | Why are all the blotches on the near side?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Did Mars have seas?
| style="border: 0px; color:red;" | Yes (briefly?)
|-
| style="border: 0px; text-align: right" | Was there life on Mars?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's Titan like?
| style="border: 0px; color:red;" | Cold, yellow, lakes + rivers (methane)
|-
| style="border: 0px; text-align: right" | What was Earth like during the Hadean?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Is the Oort Cloud a real thing?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Why is the Sun's corona so hot?
| style="border: 0px; color:red;" | Something about magnets?
|-
| style="border: 0px; text-align: right" | What are comets like?
| style="border: 0px; color:red;" | Precipitous
|-
| style="border: 0px; text-align: right" | Where's Philae, exactly?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's Pluto like?
| style="border: 0px; color:red;" rowspan="2" | [Soon!]
|-
| style="border: 0px; text-align: right" | What's Charon like?
|-
| style="border: 0px; text-align: right" | Why don't we have in-between-sized planets?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's Ceres like?
| style="border: 0px; color:red;" | [Working on it!]
|-
| style="border: 0px; text-align: right" | Why is Europa so wierd-looking and pretty?
| style="border: 0px; color:red;" | Ice over a water ocean
|-
| style="border: 0px; text-align: right" | Why is Io so weird-looking?
| style="border: 0px; color:red;" | Sulfur volcanoes (? in the wrong places?)
|-
| style="border: 0px; text-align: right" | Why are so many Kuiper Belt objects red?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What are those spots on Ceres?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's in the seas under Europa's ice?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Which of the other moons have seas?
| style="border: 0px; color:red;" | Several
|-
| style="border: 0px; text-align: right" | What are the big white things in Titan's Lakes?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What do Jupiter's clouds look like up close?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's all that red stuff in the Great Red Spot?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's pushing the Pioneer Probes?
| style="border: 0px; color:red;" | Heat from the RTG
|-
| style="border: 0px; text-align: right" | What pushes spacecraft slightly during flybys?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Where are all the Sun's Neutrinos?
| style="border: 0px; color:red;" | Oscillating
|-
| style="border: 0px; text-align: right" | Why is there so much air on Titan?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Why does the Kuiper Belt Stop?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Why is Iapetus weird-colored?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Why does Iapetus have a belt?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | What's the deal with Miranda?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Did Uranus and Neptune change places?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Did the Late Heavy Bombardment happen?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Did life start before it?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Is Europa covered in ice spikes?
| style="border: 0px;" |
|-
| style="border: 0px; text-align: right" | Why haven't we built a big inflatable extreme sports complex on the moon?
| style="border: 0px;" |
|}

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Charts]]
[[Category:Soccer]]
[[Category:Space]]
[[Category:Astronomy]]

1546: Tamagotchi Hive

2015-07-05T08:18:17Z

Sabik: /* Explanation */ +simulated reality / simulation hypothesis

{{comic
| number = 1546
| date = July 3, 2015
| title = Tamagotchi Hive
| image = tamagotchi_hive.png
| titletext = The Singularity happened, but not to us.
}}

==Explanation==
{{incomplete|Explain the comic and the title text}}
A part of the "[[My Hobby]]" series, this describes a distributed computing network using an automated system to simultaneously run trillions of Tamagotchis. As with most of the "My Hobby" series, the concept would work, and is closely connected to real world activities, but twisted enough to make it inherently absurd.

A {{w|Tamagotchi}} is a keychain-sized virtual pet simulation game from 1996. Ostensibly for children, they had appeal for people of all ages. The characters are colorful and simplistically designed creatures based on animals, objects, or people. Beginning with the 2004 Tamagotchi Plus/Connection, a second wave of Tamagotchi toys emerged, featuring a different graphic design by JINCO and gameplay which elaborated upon the first generations. However, the story behind the games remained the same: Tamagotchis are a small alien species that deposited an egg on Earth to see what life was like, and it is up to the player to raise the egg into an adult creature. The creature goes through several stages of growth, and will develop differently depending on the care the player provides, with better care resulting in an adult creature that is smarter, happier, and requires less attention. Gameplay can vary widely between models, and some models, such as TamagoChu, require little to no care from the player. Tamagotchi has a large fan base.

{{w|Distributed computing}} is a field of computer science that studies distributed systems. A distributed system is a software system in which components located on networked computers communicate and coordinate their actions by passing messages. The components interact with each other in order to achieve a common goal. Examples of distributed systems vary from {{w|Service-oriented architecture|service-oriented architecture}} based systems to {{w|multiplayer online games}} to {{w|peer-to-peer}} applications. Distributed computing is often used for tasks that require resources which would otherwise be impossible or prohibitively expensive to manage with single computers. This may include large {{w|Bitcoin network}} mining operations, the {{w|Worldwide LHC Computing Grid}} or, yes, running trillions of simultaneous Tamagotchis using an AI protocol. That said, using AI to keep trillions of Tamagotchis perfectly taken care of is a complete waste of time; the whole point of Tamagotchi is the challenge of caring for the digital pet yourself.

The singularity in the title text refers to {{w|technological singularity}} which would result in an {{w|intelligence explosion}} where artificial intelligence would take over, in particular {{w|simulated reality}} and the {{w|simulation hypothesis}}. The image and the title text resemble the scenario in {{w|The Matrix}}, but the implication is that the author takes care of a population of virtual creatures rather than an AI running over the human population.

==Transcript==
:My Hobby
:[A tree graph of Tamagotchis.]
:Running a massive distributed computing project that simulates trillions and trillions of Tamagotchis and keeps them all constantly fed and happy

[[Category:My_Hobby]]

{{comic discussion}}

Talk:1016: Valentine Dilemma

2014-02-10T08:34:41Z

Sabik: laptop or stapler?

It really depends on how good the hammers are. Good, solid machined hammers are enough to win any girl's heart. '''[[User:Davidy22|Davidy22]]'''[[User talk:Davidy22|<tt>[talk]</tt>]] 13:07, 18 February 2013 (UTC)

In frame 4, is Megan holding a laptop or the stapler? Looks more like a stapler... [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 08:34, 10 February 2014 (UTC)

Talk:1231: Habitable Zone

2014-01-19T04:31:01Z

Sabik: Dopler spectroscopy

Even if you placed the mirror in Space, it would be incredibly obvious what is going on. I don't think this would work. [[Special:Contributions/96.251.85.48|96.251.85.48]] 06:56, 28 June 2013 (UTC)

:For this trick to work, the mirror would need to be placed AT LEAST two light years away and be at least 1AU big. Somehow I don't think this is worth it. Alternatively, you need more complicated optical system which would not only mirror Earth, but also create illusion it's further away. I still think such system would be more costly to build that ISS. Or ... well ... you could put an LCD display directly over the telescope. That's doable, cheap and as a bonus you can display planets from sci-fi there. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 08:44, 28 June 2013 (UTC)

::The mirror could be much smaller and closer if it's convex. PS. I don't know the 'rules' for posting, so apologies if I'm doing it wrong.[[Special:Contributions/24.72.12.221|24.72.12.221]] 13:46, 1 July 2013 (UTC)

::Under Hkmaly's initial proposal, the astronomer would have to make two observations, 4 years apart, in order to see the "other" telescope. [[User:Elsbree|Elsbree]] ([[User talk:Elsbree|talk]]) 07:13, 29 June 2013 (UTC)

Since when do we have terrestrial telescopes that can directly resolve exoplanets? I think we're still at the stage where we get excited by troughs in light curves EDIT: TIL that there are specific techniques for exactly that: {{w|Nulling interferometry}} and {{w|Vortex coronagraph}}s. Still, they may work for hot Jupiters, but don't think we can detect Goldilocks exoplanets from the ground yet; much less see oceans and visible weather. [[Special:Contributions/220.224.246.97|220.224.246.97]] 09:14, 28 June 2013 (UTC)

::You can't detect them from the ground, but you are invited use your pattern-recognition skills to detect planets by examining the images sent back by the Kepler telescope. It's part of the citizen-scientist project. Go to http://www.PlanetHunters.org .[[User:CoderLass|CoderLass]] ([[User talk:CoderLass|talk]]) 21:14, 10 July 2013 (UTC)

My first thought was that you need to point the mirror so that it's aimed perfectly at the Earth. Then, I realized that you can use a corner reflector so that the aim doesn't have to be precise at all. Then, I came to the following realization: what if a significant portion of the stars we see are simply reflections of our own solar system due to a massive prank done by aliens? [[Special:Contributions/174.88.153.125|174.88.153.125]] 15:22, 28 June 2013 (UTC)

:Or all of them? Of course including additional variable features like red shift. So [http://commons.wikimedia.org/wiki/File:Universum.jpg they were right!] Forever alone... --[[User:Kronf|Kronf]] ([[User talk:Kronf|talk]]) 16:31, 28 June 2013 (UTC)

:: Where would these aliens reside? Either we're pranking ourselves, or there are other stars. [[Special:Contributions/220.224.246.97|220.224.246.97]] 17:57, 28 June 2013 (UTC)

::: What if there's a mirage-like effect in space, that causes light rays to mirror back to us with some variability, maybe different sizes, shapes, colors, and the universe is actuallly quite small? I mean, other than light, do we seriously detect gravity and other stuff out there (other than the visible effects of those properties on other stuff we see)? [[Special:Contributions/189.5.110.148|189.5.110.148]] 06:17, 29 June 2013 (UTC)

:::: If the universe is curved spherically, something similar to this would actually happen. http://en.wikipedia.org/wiki/Shape_of_the_Universe [[Special:Contributions/174.88.153.125|174.88.153.125]] 16:28, 29 June 2013 (UTC)

Wouldn't reflected light make the mirror extremely bright and impossible to view directly?{{unsigned ip|49.176.71.2}}

: Depends on how far the aliens decide to put the mirror. Light gets weaker with distance, which is the same reason that distant stars (many of which are brighter than our sun) don't overwhelm us with light. Also...what if the sun is merely a reflection of something? [[Special:Contributions/174.88.153.125|174.88.153.125]] 16:28, 29 June 2013 (UTC)

A German (satirical) newspaper page had an article once, how NASA discovered a habitable planet zero light years away from Earth after they rotated the Hubble space telescope [http://www.der-postillon.com/2012/02/nasa-entdeckt-bewohnbaren-planeten-in.html]. --[[User:Chtz|Chtz]] ([[User talk:Chtz|talk]]) 22:18, 10 July 2013 (UTC)
:Please translate this. It's a great joke, but most people here will not understand. And: It's not a newspaper.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 22:31, 10 July 2013 (UTC)
::That was already the main part of the joke. If someone is interested in the rest, please use your favorite online translator. (Claiming to be a "newspaper" is also a joke, the same as claiming to exist since 1845) --[[User:Chtz|Chtz]] ([[User talk:Chtz|talk]]) 10:35, 11 July 2013 (UTC)

::[http://pastebin.com/wX9j6X3Y I've translated it.] --[[User:Kronf|Kronf]] ([[User talk:Kronf|talk]]) 12:55, 2 August 2013 (UTC)

Exoplanet detection techniques like Doppler spetroscopy have to make corrections for the motion of the Earth. Omitting such corrections will result in the "discovery" of a planet which is actually the Earth... [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 04:31, 19 January 2014 (UTC)

Talk:1292: Pi vs. Tau

2013-11-20T07:13:29Z

Sabik: re 287

I started an explanation. Hopefully others will help improve it, as I don't think it's quite adequate. [[Special:Contributions/199.27.130.174|199.27.130.174]] 05:32, 18 November 2013 (UTC)

The comic currently shows the symbol π (pi) in all three cases, but it should have the symbol τ (tau) in the rightmost case. I'm sure there is a compromise symbol "pau" too. Maybe with a deformed left leg? [[Special:Contributions/141.101.97.4|141.101.97.4]] 07:07, 18 November 2013 (UTC)

WolframAlpha gives
<pre>
4.5545743763144164456766617143366171162404440766665105335330776311513504520604364524762740226212061363100001776216741750712622557020442741544760057441760026766230424023460366047331305225241275347777145543054127636365666430221066167347236617261603127725745513663702031155234027041040155322217227723576660045156156303357534162372112340027743775672417274565277274565735325624457113522164166560115654407251403563246444122664066521461311773474046032763760765740133706761276420415672577471077133607673035331070364705651055376634161405567176532346433567731715723623721267302576735154761375545411215522177775706407470673020025353246535120744232706060324711633457720155013202527060250466252665661576165164140301645132275526153126363575631176312270212441433434206352313125326760006365710744276056412434626534152021052065172556442150110056601034116570607064550553636566432544260105637423220411372664024454234201642615033200331506013362432026775605543212342336511350621361642654426372425415023071413764173735461042064323757413414533013..._8</pre> which does indeed have four 666 sequences. [[Special:Contributions/141.101.99.254|141.101.99.254]] 08:06, 18 November 2013 (UTC)
This number contains 7777, 000 and 444 twice, though. [[Special:Contributions/141.101.93.11|141.101.93.11]] 09:08, 18 November 2013 (UTC)

Wrote the transcript, not sure if I explained the visual well enough, so I left the incomplete tag if someone else has a better idea. Should suffice for understanding however, considering the content [[Special:Contributions/108.162.248.18|108.162.248.18]] 08:55, 18 November 2013 (UTC)

----

(The discussion about different results was trimmed)

Wolfram gives the result with 666

http://www.wolframalpha.com/input/?i=1.5+pi+octal
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022
</pre>
The Unix arbitrary precision calculator gives the result without

$ echo "scale=200; obase=8; 6*a(1)" | bc -l
<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
Any suggestions how we can check them?

"Randall says so" is probably correct, but insufficient :-) {{unsigned|Mike}}

:Please use the <nowiki><pre></nowiki> tag for this long numbers.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 09:20, 18 November 2013 (UTC)

Testing Wolfram Alpha with <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8 in decimal</pre> and <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000_8 in decimal</pre> both indicate the approximation is only accurate to a limited degree.
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>

The method I used to get the value I put in the text was; I used the following command to generate my approximation:
<pre>echo 'scale=200; obase=8; a(1) * 6' | bc -l | tr -d ' \\\n' ; echo</pre> which outputs<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
In 'bc'', a(1) is arctangent of 1 (i.e. 45 degrees, or pi/4); (pi/4 * 6) should be equal to 'pau'. I additionally checked the result using base 2 encoding, and converted each three bit binary value into an octal value. The decimal value of pi (using a(1) * 4) matches with the value of pi to at lease 1000 digits.
[[Special:Contributions/173.245.54.86|173.245.54.86]] 09:21, 18 November 2013 (UTC)

Both Maxima and the GNU Emacs calculator output as the first 1000 octal digits:
<pre>
4.5545743763144164432362345144750501224254715730156503147633545270030431677126116550546747570313312523403514716576464333172731124310201076447270723624573721640220437652155065544220143116155742515634462136362517441011077702611156024117447125224176203716336742057353303216470257662666744627534325504334506002730517102547504145216661211250027531716641276765735563341721214013553453654106045245066401141437740626707757305450703606440651111775270032710035521352101513622062164457304326450524432531652666626042202562202550566425643040556365710250031642467447605663240661743600041052212627767073277600402572027316222345356036301002572541750000114422036312122341474267232761775450071652613627306745074150251171507720277250030270442257106542456441722455345340370205646442156334125564557520336340223313312556634450170626417234376702443117031135045420165467426237454754566012204316130023063506430063362203021262434464410604275224606523356702572610031171344411766505734615256121034660773306140032365326415773227551
</pre>
This also agrees with the first 220 digits of the previous result (last two digits above are 57 vs 61 here, maybe due to rounding when converting to octal). Again, no 666 within the first 200 digits. The Wolfram result deviates from this at the 18th digit already. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 10:21, 18 November 2013 (UTC)

Also e+2 does not contain the substring '666':
<pre>echo "scale=200; obase=8; e(1) + 2" | bc -l</pre>
<pre>4.55760521305053551246527734254200471723636166134705407470551551265170233101050620637674622347347044466373713722774330661414353543664033100253542141365517370755272577262541110317650765740633550205306625</pre>--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 10:43, 18 November 2013 (UTC)

: A sudden flash of realization: are we getting nerd-sniped here?--[[Special:Contributions/108.162.254.168|108.162.254.168]] 11:55, 18 November 2013 (UTC)

: The claim is clearly about e+2, making Dgbrt's comment closest to the right direction. [[Special:Contributions/173.245.54.40|173.245.54.40]] 12:03, 18 November 2013 (UTC)

When I take Wolfram alpha's octal(pi*1.5) I get the first 303 (base 10) characters as this:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022106616734723661726160312772574551366370203115523402704104015532221722772357666
</pre>
200(base 10) is 310(base 8) so in the fist '200' characters, 666 shows up 4 times (5 if you count 6666 as twice?) [[User:Xami|Xami]] ([[User talk:Xami|talk]]) 14:01, 18 November 2013 (UTC)

: The Wolfram result is what you get when you calculate pi*3/2 in decimal, round to 14 digits after the decimal point and then convert to octal. That is, 4.7123889803846910 converted to octal. Definitely, this won't give you 200 digits precision. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 15:15, 18 November 2013 (UTC)
:: It lines up too perfectly to be a coincidence. It fits all the requirements: has 666 four times within 2008 digits, and although 0000, 222, 444, and 7777 appear, they only appear once as a run. You can't double count 7777 as two 777's because it is a single run. If WolframAlpha doesn't give the correct precision, it is likely that Randall made the same error. --[[User:RainbowDash|RainbowDash]] ([[User talk:RainbowDash|talk]]) 16:59, 18 November 2013 (UTC)

Being τ, tau, is already being expressed in terms of π, pi, it shows bias. (Though I think Pau would lead to some interesting spherical geometry equations. ~~Drifter {{unsigned ip|108.162.219.214}}

The bias is worse than that: From the perspective of π, the discussion is about multiples of π, so (3/2)π (that is 3π/2 = 3τ/4) is indeed the compromise between π and 2π. But from the perspective of τ, the discussion is about fractions of τ, so the compromise between τ and τ/2 is τ/(3/2) (that is 2τ/3 = 4π/3). Maybe we can call this ‘ti’ (or ‘tie’, pace 173.245.53.184 below). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:47, 18 November 2013 (UTC)

Actually, both compromises are wrong. (3/2)π is the arithmetic mean of π and τ, while τ/(3/2) is their harmonic mean. But for geometric ratios (which these are), the appropriate mean is generally the geometric mean (hence the name). You can see how even-handed this is: it's (√2)π = τ/(√2). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:50, 18 November 2013 (UTC)

---

I am in favour of just calling it ti(e). --[[Special:Contributions/173.245.53.184|173.245.53.184]] 17:52, 18 November 2013 (UTC)

---

There are real world uses to both Tau and Pi: Pi is the number that relates to what you get when you measure a circle (the distanced around divided by the distance across); and Tau is get when you draw a circle (the distance around divided by the distance from the center). It is the difference between a mic (aka "micrometer" http://en.wikipedia.org/wiki/Micrometer ) and a protractor. Tau might have some mathematical advantages in both 2D and 3D in that it has no integer attached to it to find either circumference (2D) or surface area (3D) which makes radians and solid angles simpler. However, that advantage is lost in other dimensions and for the area of a circle.

Pau, of course, has a 61% chance of going to the dribbling spheroid hall of fame. (ref: http://www.basketball-reference.com/players/g/gasolpa01.html ), to which neither Tau nor Pi can hold a candle.~~Remo ( [[Special:Contributions/199.27.128.183|199.27.128.183]] 19:19, 18 November 2013 (UTC) )

---

The differences between Wolfram and BC really bothered me since I have used both for precision calculation in the past. The long and short of the matter, having done most of the maths 'long hand', BC is correct, Wolfram is wrong, and sadly, Randall was also wrong. It seems as tho Wolfram is rounding pi*1.5 to around 15 decimals but leaving the 9 repeating before converting to Octal.

If you take the output of octal(pi * 1.5) and paste it back into the input like so:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777_8
</pre>
Wolfram gives you back (converted to decimal):
<pre>
4.71238898038468999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
</pre>
If you give that same input to BC and ask it to convert to decimal you get:
<pre>
4.712388980384689999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999992894219160392567888
</pre>
If you do the math long hand out to 55 decimal places, pi * 1.5 equals:
<pre>
4.712388980384689857693965074919254326295754099062658731462416...
</pre>
Converting that by hand into octal is a bit of a pain, but if you do, at the 18th decimal place where BC and Wolfram differ you end up with the following:
<pre>
0.000000000000000183697019872102976583909889841150158731462416... is your remainder to be converted so far
0.000000000000000055511151231257827021181583404541015625 = 8 ^ -18
</pre>
Wolfram gives the 18th decimal as 5, BC as 3. I can't see 5 going into 18 5 times, but 3 times fits nicely.
--[[User:DarkJMKnight|DarkJMKnight]] ([[User talk:DarkJMKnight|talk]]) 20:04, 18 November 2013 (UTC)

Looks like Wolfram is simply using floating-point mathematics, presumably the IEEE "double precision". Interestingly, this is not the first time floating-point maths has been a problem; in [[287]], a similar problem caused an unintended trivial solution. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 04:41, 19 November 2013 (UTC)
* On second thoughts, there's no indication that he used Wolfram Alpha; as with [[287]], it simply could have been a Perl script (or Python or pretty much any programming language). [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 05:25, 19 November 2013 (UTC)

---

How can 200 be octal and then mean 310 decimal???
If 200 were octal, that would be 128 decimal, so we would end up writing 128 decimals.
Of course 310 octal is 200 decimal, but taking 2008 to mean 31010 is plain crazy, even if it's the only way to make it fit the "four times 666" constraint!
What am I missing here? [[Special:Contributions/173.245.53.149|173.245.53.149]] 21:27, 18 November 2013 (UTC)

This Mathematica code searches for the pattern 666 in the octal expansion of 1.5 pi:
<pre>digits = RealDigits[3*Pi/2, 8, 10000][[1]]; Select[Range[10000 - 2], Take[digits, {#, # + 2}] == {6, 6, 6} &]
{279, 326, 495, 496, 3430, 3728, 4153, 6040, 7031, 7195, 7647, 7732, 8353, 8435, 8436, 8575, 8768, 9008}</pre>
These positions start counting with the leading "4" as position 1. It does not occur in the first 200 digits, but occurs 18 times in the first 10,000 digits. Many other digit combinations occur more times in the first 10,000 digits, including "123" (23 times), "222" (21 times), and "555" (26 times). Note that "xkcd" converted to numbers (a=1, b=2, etc.) is 24, 11, 3, 4. The combination 241134 first occurs in 1.5 pi at digit number 250,745. [[User:Dcoetzee|Dcoetzee]] ([[User talk:Dcoetzee|talk]]) 06:44, 19 November 2013 (UTC)

Wow, this filled up fast. Is it time to remove the Incomplete tag yet? [[Special:Contributions/199.27.128.66|199.27.128.66]] 03:14, 19 November 2013 (UTC)

:Please do your adds at the bottom. Otherwise it looks like as the first discussion here and everybody will ignore your comment.
:My answer is: NO. We still have to figure out if Randall is wrong or just using an algorithm nobody does understand right now.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:10, 19 November 2013 (UTC)

---

Someone said there's no indication that Randall used Wolfram, and that double-precision IEEE numbers in mostly any language would cause the same error.
This is not true: IEEE double precision numbers (binary64) are stored internally in binary.
Converting them to octal would give at most 18 nonzero significant (octal) digits, and from that point on all additional digits would be zeros (remember that an octal digit is equivalent to three bits).
What Wolfram does is rounding to a decimal number, which is not round in octal.

I think the previous is an indication that Randall did indeed use Wolfram.
Added to that, he used Wolfram in several what-if's, and in one case he used it so heavily that his IP got temporarily banned from Wolfram.
This leaves little or no doubts in me that Wolfram is the source of Randall's mistake.

Also, I still would like to know why everybody is interpreting "200 digits" as "2008 digits" and pretending that's equal to "31010 digits" instead of "12810 digits".

And out of curiosity, what happened with [[287]] and floating point numbers?
The explainxkcd for 287 says nothing about floating point.

[[Special:Contributions/173.245.53.145|173.245.53.145]] 22:09, 19 November 2013 (UTC)
* With [[287]], there was only meant to be one solution, the other solution was unintended. It's mentioned in the discussion only, not in the body of the explanation, but there's a link to an interview where he indicates that it was indeed unintentional. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 07:13, 20 November 2013 (UTC)

;What is the period of the wolfram answer?
What is the repeat period of the octal answer with the 666's, (the length of the repetend) i.e. the one that comes from Wolfram, that is converting 4.71238898038469 decimal to octal? And how many 666's are in the full repetend? Oooh - I like that new word - thanks to {{w|repeating decimal}}! [[User:Nealmcb|Nealmcb]] ([[User talk:Nealmcb|talk]]) 23:22, 19 November 2013 (UTC)

:Dunno, either Randall uses WolframAlpha whithout further checks, so he has to check his sources, or we all are just dumb.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 23:54, 19 November 2013 (UTC)

Talk:1292: Pi vs. Tau

2013-11-19T05:25:41Z

Sabik: Not necessarily Wolfram alpha

Wow, this filled up fast. Is it time to remove the Incomplete tag yet? [[Special:Contributions/199.27.128.66|199.27.128.66]] 03:14, 19 November 2013 (UTC)

I started an explanation. Hopefully others will help improve it, as I don't think it's quite adequate. [[Special:Contributions/199.27.130.174|199.27.130.174]] 05:32, 18 November 2013 (UTC)

The comic currently shows the symbol π (pi) in all three cases, but it should have the symbol τ (tau) in the rightmost case. I'm sure there is a compromise symbol "pau" too. Maybe with a deformed left leg? [[Special:Contributions/141.101.97.4|141.101.97.4]] 07:07, 18 November 2013 (UTC)

WolframAlpha gives
<pre>
4.5545743763144164456766617143366171162404440766665105335330776311513504520604364524762740226212061363100001776216741750712622557020442741544760057441760026766230424023460366047331305225241275347777145543054127636365666430221066167347236617261603127725745513663702031155234027041040155322217227723576660045156156303357534162372112340027743775672417274565277274565735325624457113522164166560115654407251403563246444122664066521461311773474046032763760765740133706761276420415672577471077133607673035331070364705651055376634161405567176532346433567731715723623721267302576735154761375545411215522177775706407470673020025353246535120744232706060324711633457720155013202527060250466252665661576165164140301645132275526153126363575631176312270212441433434206352313125326760006365710744276056412434626534152021052065172556442150110056601034116570607064550553636566432544260105637423220411372664024454234201642615033200331506013362432026775605543212342336511350621361642654426372425415023071413764173735461042064323757413414533013..._8</pre> which does indeed have four 666 sequences. [[Special:Contributions/141.101.99.254|141.101.99.254]] 08:06, 18 November 2013 (UTC)
This number contains 7777, 000 and 444 twice, though. [[Special:Contributions/141.101.93.11|141.101.93.11]] 09:08, 18 November 2013 (UTC)

Wrote the transcript, not sure if I explained the visual well enough, so I left the incomplete tag if someone else has a better idea. Should suffice for understanding however, considering the content [[Special:Contributions/108.162.248.18|108.162.248.18]] 08:55, 18 November 2013 (UTC)

----

(The discussion about different results was trimmed)

Wolfram gives the result with 666

http://www.wolframalpha.com/input/?i=1.5+pi+octal
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022
</pre>
The Unix arbitrary precision calculator gives the result without

$ echo "scale=200; obase=8; 6*a(1)" | bc -l
<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
Any suggestions how we can check them?

"Randall says so" is probably correct, but insufficient :-) {{unsigned|Mike}}

:Please use the <nowiki><pre></nowiki> tag for this long numbers.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 09:20, 18 November 2013 (UTC)

Testing Wolfram Alpha with <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8 in decimal</pre> and <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000_8 in decimal</pre> both indicate the approximation is only accurate to a limited degree.
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>

The method I used to get the value I put in the text was; I used the following command to generate my approximation:
<pre>echo 'scale=200; obase=8; a(1) * 6' | bc -l | tr -d ' \\\n' ; echo</pre> which outputs<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
In 'bc'', a(1) is arctangent of 1 (i.e. 45 degrees, or pi/4); (pi/4 * 6) should be equal to 'pau'. I additionally checked the result using base 2 encoding, and converted each three bit binary value into an octal value. The decimal value of pi (using a(1) * 4) matches with the value of pi to at lease 1000 digits.
[[Special:Contributions/173.245.54.86|173.245.54.86]] 09:21, 18 November 2013 (UTC)

Both Maxima and the GNU Emacs calculator output as the first 1000 octal digits:
<pre>
4.5545743763144164432362345144750501224254715730156503147633545270030431677126116550546747570313312523403514716576464333172731124310201076447270723624573721640220437652155065544220143116155742515634462136362517441011077702611156024117447125224176203716336742057353303216470257662666744627534325504334506002730517102547504145216661211250027531716641276765735563341721214013553453654106045245066401141437740626707757305450703606440651111775270032710035521352101513622062164457304326450524432531652666626042202562202550566425643040556365710250031642467447605663240661743600041052212627767073277600402572027316222345356036301002572541750000114422036312122341474267232761775450071652613627306745074150251171507720277250030270442257106542456441722455345340370205646442156334125564557520336340223313312556634450170626417234376702443117031135045420165467426237454754566012204316130023063506430063362203021262434464410604275224606523356702572610031171344411766505734615256121034660773306140032365326415773227551
</pre>
This also agrees with the first 220 digits of the previous result (last two digits above are 57 vs 61 here, maybe due to rounding when converting to octal). Again, no 666 within the first 200 digits. The Wolfram result deviates from this at the 18th digit already. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 10:21, 18 November 2013 (UTC)

Also e+2 does not contain the substring '666':
<pre>echo "scale=200; obase=8; e(1) + 2" | bc -l</pre>
<pre>4.55760521305053551246527734254200471723636166134705407470551551265170233101050620637674622347347044466373713722774330661414353543664033100253542141365517370755272577262541110317650765740633550205306625</pre>--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 10:43, 18 November 2013 (UTC)

: A sudden flash of realization: are we getting nerd-sniped here?--[[Special:Contributions/108.162.254.168|108.162.254.168]] 11:55, 18 November 2013 (UTC)

: The claim is clearly about e+2, making Dgbrt's comment closest to the right direction. [[Special:Contributions/173.245.54.40|173.245.54.40]] 12:03, 18 November 2013 (UTC)

When I take Wolfram alpha's octal(pi*1.5) I get the first 303 (base 10) characters as this:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022106616734723661726160312772574551366370203115523402704104015532221722772357666
</pre>
200(base 10) is 310(base 8) so in the fist '200' characters, 666 shows up 4 times (5 if you count 6666 as twice?) [[User:Xami|Xami]] ([[User talk:Xami|talk]]) 14:01, 18 November 2013 (UTC)

: The Wolfram result is what you get when you calculate pi*3/2 in decimal, round to 14 digits after the decimal point and then convert to octal. That is, 4.7123889803846910 converted to octal. Definitely, this won't give you 200 digits precision. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 15:15, 18 November 2013 (UTC)
:: It lines up too perfectly to be a coincidence. It fits all the requirements: has 666 four times within 2008 digits, and although 0000, 222, 444, and 7777 appear, they only appear once as a run. You can't double count 7777 as two 777's because it is a single run. If WolframAlpha doesn't give the correct precision, it is likely that Randall made the same error. --[[User:RainbowDash|RainbowDash]] ([[User talk:RainbowDash|talk]]) 16:59, 18 November 2013 (UTC)

Being τ, tau, is already being expressed in terms of π, pi, it shows bias. (Though I think Pau would lead to some interesting spherical geometry equations. ~~Drifter {{unsigned ip|108.162.219.214}}

The bias is worse than that: From the perspective of π, the discussion is about multiples of π, so (3/2)π (that is 3π/2 = 3τ/4) is indeed the compromise between π and 2π. But from the perspective of τ, the discussion is about fractions of τ, so the compromise between τ and τ/2 is τ/(3/2) (that is 2τ/3 = 4π/3). Maybe we can call this ‘ti’ (or ‘tie’, pace 173.245.53.184 below). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:47, 18 November 2013 (UTC)

Actually, both compromises are wrong. (3/2)π is the arithmetic mean of π and τ, while τ/(3/2) is their harmonic mean. But for geometric ratios (which these are), the appropriate mean is generally the geometric mean (hence the name). You can see how even-handed this is: it's (√2)π = τ/(√2). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:50, 18 November 2013 (UTC)

---

I am in favour of just calling it ti(e). --[[Special:Contributions/173.245.53.184|173.245.53.184]] 17:52, 18 November 2013 (UTC)

---

There are real world uses to both Tau and Pi: Pi is the number that relates to what you get when you measure a circle (the distanced around divided by the distance across); and Tau is get when you draw a circle (the distance around divided by the distance from the center). It is the difference between a mic (aka "micrometer" http://en.wikipedia.org/wiki/Micrometer ) and a protractor. Tau might have some mathematical advantages in both 2D and 3D in that it has no integer attached to it to find either circumference (2D) or surface area (3D) which makes radians and solid angles simpler. However, that advantage is lost in other dimensions and for the area of a circle.

Pau, of course, has a 61% chance of going to the dribbling spheroid hall of fame. (ref: http://www.basketball-reference.com/players/g/gasolpa01.html ), to which neither Tau nor Pi can hold a candle.~~Remo ( [[Special:Contributions/199.27.128.183|199.27.128.183]] 19:19, 18 November 2013 (UTC) )

---

The differences between Wolfram and BC really bothered me since I have used both for precision calculation in the past. The long and short of the matter, having done most of the maths 'long hand', BC is correct, Wolfram is wrong, and sadly, Randall was also wrong. It seems as tho Wolfram is rounding pi*1.5 to around 15 decimals but leaving the 9 repeating before converting to Octal.

If you take the output of octal(pi * 1.5) and paste it back into the input like so:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777_8
</pre>
Wolfram gives you back (converted to decimal):
<pre>
4.71238898038468999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
</pre>
If you give that same input to BC and ask it to convert to decimal you get:
<pre>
4.712388980384689999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999992894219160392567888
</pre>
If you do the math long hand out to 55 decimal places, pi * 1.5 equals:
<pre>
4.712388980384689857693965074919254326295754099062658731462416...
</pre>
Converting that by hand into octal is a bit of a pain, but if you do, at the 18th decimal place where BC and Wolfram differ you end up with the following:
<pre>
0.000000000000000183697019872102976583909889841150158731462416... is your remainder to be converted so far
0.000000000000000055511151231257827021181583404541015625 = 8 ^ -18
</pre>
Wolfram gives the 18th decimal as 5, BC as 3. I can't see 5 going into 18 5 times, but 3 times fits nicely.
--[[User:DarkJMKnight|DarkJMKnight]] ([[User talk:DarkJMKnight|talk]]) 20:04, 18 November 2013 (UTC)

Looks like Wolfram is simply using floating-point mathematics, presumably the IEEE "double precision". Interestingly, this is not the first time floating-point maths has been a problem; in [[287]], a similar problem caused an unintended trivial solution. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 04:41, 19 November 2013 (UTC)
* On second thoughts, there's no indication that he used Wolfram Alpha; as with [[287]], it simply could have been a Perl script (or Python or pretty much any programming language). [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 05:25, 19 November 2013 (UTC)

---

How can 200 be octal and then mean 310 decimal???
If 200 were octal, that would be 128 decimal, so we would end up writing 128 decimals.
Of course 310 octal is 200 decimal, but taking 2008 to mean 31010 is plain crazy, even if it's the only way to make it fit the "four times 666" constraint!
What am I missing here? [[Special:Contributions/173.245.53.149|173.245.53.149]] 21:27, 18 November 2013 (UTC)

Talk:1292: Pi vs. Tau

2013-11-19T04:41:14Z

Sabik: +note similar problem in comic 287

Wow, this filled up fast. Is it time to remove the Incomplete tag yet? [[Special:Contributions/199.27.128.66|199.27.128.66]] 03:14, 19 November 2013 (UTC)

I started an explanation. Hopefully others will help improve it, as I don't think it's quite adequate. [[Special:Contributions/199.27.130.174|199.27.130.174]] 05:32, 18 November 2013 (UTC)

The comic currently shows the symbol π (pi) in all three cases, but it should have the symbol τ (tau) in the rightmost case. I'm sure there is a compromise symbol "pau" too. Maybe with a deformed left leg? [[Special:Contributions/141.101.97.4|141.101.97.4]] 07:07, 18 November 2013 (UTC)

WolframAlpha gives
<pre>
4.5545743763144164456766617143366171162404440766665105335330776311513504520604364524762740226212061363100001776216741750712622557020442741544760057441760026766230424023460366047331305225241275347777145543054127636365666430221066167347236617261603127725745513663702031155234027041040155322217227723576660045156156303357534162372112340027743775672417274565277274565735325624457113522164166560115654407251403563246444122664066521461311773474046032763760765740133706761276420415672577471077133607673035331070364705651055376634161405567176532346433567731715723623721267302576735154761375545411215522177775706407470673020025353246535120744232706060324711633457720155013202527060250466252665661576165164140301645132275526153126363575631176312270212441433434206352313125326760006365710744276056412434626534152021052065172556442150110056601034116570607064550553636566432544260105637423220411372664024454234201642615033200331506013362432026775605543212342336511350621361642654426372425415023071413764173735461042064323757413414533013..._8</pre> which does indeed have four 666 sequences. [[Special:Contributions/141.101.99.254|141.101.99.254]] 08:06, 18 November 2013 (UTC)
This number contains 7777, 000 and 444 twice, though. [[Special:Contributions/141.101.93.11|141.101.93.11]] 09:08, 18 November 2013 (UTC)

Wrote the transcript, not sure if I explained the visual well enough, so I left the incomplete tag if someone else has a better idea. Should suffice for understanding however, considering the content [[Special:Contributions/108.162.248.18|108.162.248.18]] 08:55, 18 November 2013 (UTC)

----

(The discussion about different results was trimmed)

Wolfram gives the result with 666

http://www.wolframalpha.com/input/?i=1.5+pi+octal
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022
</pre>
The Unix arbitrary precision calculator gives the result without

$ echo "scale=200; obase=8; 6*a(1)" | bc -l
<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
Any suggestions how we can check them?

"Randall says so" is probably correct, but insufficient :-) {{unsigned|Mike}}

:Please use the <nowiki><pre></nowiki> tag for this long numbers.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 09:20, 18 November 2013 (UTC)

Testing Wolfram Alpha with <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8 in decimal</pre> and <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000_8 in decimal</pre> both indicate the approximation is only accurate to a limited degree.
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>

The method I used to get the value I put in the text was; I used the following command to generate my approximation:
<pre>echo 'scale=200; obase=8; a(1) * 6' | bc -l | tr -d ' \\\n' ; echo</pre> which outputs<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
In 'bc'', a(1) is arctangent of 1 (i.e. 45 degrees, or pi/4); (pi/4 * 6) should be equal to 'pau'. I additionally checked the result using base 2 encoding, and converted each three bit binary value into an octal value. The decimal value of pi (using a(1) * 4) matches with the value of pi to at lease 1000 digits.
[[Special:Contributions/173.245.54.86|173.245.54.86]] 09:21, 18 November 2013 (UTC)

Both Maxima and the GNU Emacs calculator output as the first 1000 octal digits:
<pre>
4.5545743763144164432362345144750501224254715730156503147633545270030431677126116550546747570313312523403514716576464333172731124310201076447270723624573721640220437652155065544220143116155742515634462136362517441011077702611156024117447125224176203716336742057353303216470257662666744627534325504334506002730517102547504145216661211250027531716641276765735563341721214013553453654106045245066401141437740626707757305450703606440651111775270032710035521352101513622062164457304326450524432531652666626042202562202550566425643040556365710250031642467447605663240661743600041052212627767073277600402572027316222345356036301002572541750000114422036312122341474267232761775450071652613627306745074150251171507720277250030270442257106542456441722455345340370205646442156334125564557520336340223313312556634450170626417234376702443117031135045420165467426237454754566012204316130023063506430063362203021262434464410604275224606523356702572610031171344411766505734615256121034660773306140032365326415773227551
</pre>
This also agrees with the first 220 digits of the previous result (last two digits above are 57 vs 61 here, maybe due to rounding when converting to octal). Again, no 666 within the first 200 digits. The Wolfram result deviates from this at the 18th digit already. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 10:21, 18 November 2013 (UTC)

Also e+2 does not contain the substring '666':
<pre>echo "scale=200; obase=8; e(1) + 2" | bc -l</pre>
<pre>4.55760521305053551246527734254200471723636166134705407470551551265170233101050620637674622347347044466373713722774330661414353543664033100253542141365517370755272577262541110317650765740633550205306625</pre>--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 10:43, 18 November 2013 (UTC)

: A sudden flash of realization: are we getting nerd-sniped here?--[[Special:Contributions/108.162.254.168|108.162.254.168]] 11:55, 18 November 2013 (UTC)

: The claim is clearly about e+2, making Dgbrt's comment closest to the right direction. [[Special:Contributions/173.245.54.40|173.245.54.40]] 12:03, 18 November 2013 (UTC)

When I take Wolfram alpha's octal(pi*1.5) I get the first 303 (base 10) characters as this:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022106616734723661726160312772574551366370203115523402704104015532221722772357666
</pre>
200(base 10) is 310(base 8) so in the fist '200' characters, 666 shows up 4 times (5 if you count 6666 as twice?) [[User:Xami|Xami]] ([[User talk:Xami|talk]]) 14:01, 18 November 2013 (UTC)

: The Wolfram result is what you get when you calculate pi*3/2 in decimal, round to 14 digits after the decimal point and then convert to octal. That is, 4.7123889803846910 converted to octal. Definitely, this won't give you 200 digits precision. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 15:15, 18 November 2013 (UTC)
:: It lines up too perfectly to be a coincidence. It fits all the requirements: has 666 four times within 2008 digits, and although 0000, 222, 444, and 7777 appear, they only appear once as a run. You can't double count 7777 as two 777's because it is a single run. If WolframAlpha doesn't give the correct precision, it is likely that Randall made the same error. --[[User:RainbowDash|RainbowDash]] ([[User talk:RainbowDash|talk]]) 16:59, 18 November 2013 (UTC)

Being τ, tau, is already being expressed in terms of π, pi, it shows bias. (Though I think Pau would lead to some interesting spherical geometry equations. ~~Drifter {{unsigned ip|108.162.219.214}}

The bias is worse than that: From the perspective of π, the discussion is about multiples of π, so (3/2)π (that is 3π/2 = 3τ/4) is indeed the compromise between π and 2π. But from the perspective of τ, the discussion is about fractions of τ, so the compromise between τ and τ/2 is τ/(3/2) (that is 2τ/3 = 4π/3). Maybe we can call this ‘ti’ (or ‘tie’, pace 173.245.53.184 below). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:47, 18 November 2013 (UTC)

Actually, both compromises are wrong. (3/2)π is the arithmetic mean of π and τ, while τ/(3/2) is their harmonic mean. But for geometric ratios (which these are), the appropriate mean is generally the geometric mean (hence the name). You can see how even-handed this is: it's (√2)π = τ/(√2). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:50, 18 November 2013 (UTC)

---

I am in favour of just calling it ti(e). --[[Special:Contributions/173.245.53.184|173.245.53.184]] 17:52, 18 November 2013 (UTC)

---

There are real world uses to both Tau and Pi: Pi is the number that relates to what you get when you measure a circle (the distanced around divided by the distance across); and Tau is get when you draw a circle (the distance around divided by the distance from the center). It is the difference between a mic (aka "micrometer" http://en.wikipedia.org/wiki/Micrometer ) and a protractor. Tau might have some mathematical advantages in both 2D and 3D in that it has no integer attached to it to find either circumference (2D) or surface area (3D) which makes radians and solid angles simpler. However, that advantage is lost in other dimensions and for the area of a circle.

Pau, of course, has a 61% chance of going to the dribbling spheroid hall of fame. (ref: http://www.basketball-reference.com/players/g/gasolpa01.html ), to which neither Tau nor Pi can hold a candle.~~Remo ( [[Special:Contributions/199.27.128.183|199.27.128.183]] 19:19, 18 November 2013 (UTC) )

---

The differences between Wolfram and BC really bothered me since I have used both for precision calculation in the past. The long and short of the matter, having done most of the maths 'long hand', BC is correct, Wolfram is wrong, and sadly, Randall was also wrong. It seems as tho Wolfram is rounding pi*1.5 to around 15 decimals but leaving the 9 repeating before converting to Octal.

If you take the output of octal(pi * 1.5) and paste it back into the input like so:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777_8
</pre>
Wolfram gives you back (converted to decimal):
<pre>
4.71238898038468999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
</pre>
If you give that same input to BC and ask it to convert to decimal you get:
<pre>
4.712388980384689999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999992894219160392567888
</pre>
If you do the math long hand out to 55 decimal places, pi * 1.5 equals:
<pre>
4.712388980384689857693965074919254326295754099062658731462416...
</pre>
Converting that by hand into octal is a bit of a pain, but if you do, at the 18th decimal place where BC and Wolfram differ you end up with the following:
<pre>
0.000000000000000183697019872102976583909889841150158731462416... is your remainder to be converted so far
0.000000000000000055511151231257827021181583404541015625 = 8 ^ -18
</pre>
Wolfram gives the 18th decimal as 5, BC as 3. I can't see 5 going into 18 5 times, but 3 times fits nicely.
--[[User:DarkJMKnight|DarkJMKnight]] ([[User talk:DarkJMKnight|talk]]) 20:04, 18 November 2013 (UTC)

Looks like Wolfram is simply using floating-point mathematics, presumably the IEEE "double precision". Interestingly, this is not the first time floating-point maths has been a problem; in [[287]], a similar problem caused an unintended trivial solution. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 04:41, 19 November 2013 (UTC)

---

How can 200 be octal and then mean 310 decimal???
If 200 were octal, that would be 128 decimal, so we would end up writing 128 decimals.
Of course 310 octal is 200 decimal, but taking 2008 to mean 31010 is plain crazy, even if it's the only way to make it fit the "four times 666" constraint!
What am I missing here? [[Special:Contributions/173.245.53.149|173.245.53.149]] 21:27, 18 November 2013 (UTC)