https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=172.70.34.91&feedformat=atomexplain xkcd - User contributions [en]2024-03-29T04:42:34ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=2607:_Geiger_Counter&diff=2306012607: Geiger Counter2022-04-16T17:22:50Z<p>172.70.34.91: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 2607<br />
| date = April 15, 2022<br />
| title = Geiger Counter<br />
| image = geiger_counter.png<br />
| titletext = At first I didn't get why they were warning me about all those birds sitting on the wire, but then I understood.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by A CLICKING BIRD COUNTER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
This comic is a simple {{w|pun}}. [[Cueball]] and [[Ponytail]] are standing in what looks to be a desert, and Cueball is holding a {{w|Geiger counter}} in his hand. Cueball remarks that he did not understand why he was asked to carry a Geiger counter, but that it then "clicked" with him.<br />
<br />
Geiger counters are devices used to measure the amount of {{w|radiation}} in an area. When a particle of ionizing radiation hits the sensor of a Geiger counter, it will give off a distinct "clicking" noise. "Click" can also be a slang term for the {{w|Eureka effect}}, a sudden moment of understanding. The pun in this comic insinuates that Cueball realized why he was asked to bring the Geiger counter when it clicked, indicating radiation nearby. In radioactive areas, it is usually a good idea to carry around some sort of radiation detector for safety reasons.<br />
<br />
This is likely a {{w|parody}} of a fairly well-known pun that takes advantage of a similar double meaning: "I wondered why the baseball was getting bigger. Then it hit me." Just as that pun uses "hit me" to mean both the action of the ball and to understand, this comic uses the "clicking" to mean both the action of the Geiger counter and to understand. A related variety of pun, told in the {{w|Narration#Third-person|third person}}, is the {{w|Tom Swifty}}.<br />
<br />
The title text is also a pun, since "I" stand under the birds on the wire (under-stood, stood under), with the implication being that some birds on the power line pooped on him.<br />
<br />
Cueball's failure to expect radiation after being issued a Geiger counter may be a reference to reports that the Russian military unwittingly exposed its soldiers to high levels of radiation during the {{w|Battle of Chernobyl}} in March and April 2022, such as by moving heavy equipment through the {{w|Red Forest}} (named for the color of trees killed by radiation) and by digging trenches in contaminated soil. <br />
<br />
note: The title text can also have a different meaning: a reference to the Hitchcock film 'The Birds'<br />
<br />
==Transcript==<br />
<br />
{{incomplete transcript}} <br />
:[Cueball and Ponytail are wearing hard hats and standing in what looks to be some sort of desert or rocky area. Cueball is holding a Geiger counter in his hands. Ponytail is holding a clipboard.]<br />
:Cueball: At first I was confused about why they wanted me to carry a Geiger counter here, but then it clicked.<br />
<br />
{{comic discussion}}<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Ponytail]]<br />
[[Category:Characters with Hats]]<br />
[[Category:Language]]<br />
[[Category:Puns]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2606:_Weird_Unicode_Math_Symbols&diff=2304102606: Weird Unicode Math Symbols2022-04-14T11:01:08Z<p>172.70.34.91: /* Explanation */ Fixed link</p>
<hr />
<div>{{comic<br />
| number = 2606<br />
| date = April 13, 2022<br />
| title = Weird Unicode Math Symbols<br />
| image = weird_unicode_math_symbols.png<br />
| titletext = U+2A0B ⨋ Mathematicians need to calm down<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by A SNAKE AVOIDING A BEE ON A WHITEBOARD - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
This comic proposes joke explanations for various {{w|unicode symbols}} with obscure or no known uses.<br />
<br />
{| class="wikitable"<br />
|+ Symbols<br />
|-<br />
! Codepoint !! Symbol !! Unicode Name !! Actual use !! Randall's meaning || Explanation<br />
|-<br />
| U+29CD || <span style="font-size: xx-large;">⧍</span> || Triangle with Serifs At Bottom || No standard use,{{citation needed}} but resembles the {{w|National Park Service}} cartographic symbol for a campsite.[https://github.com/nationalparkservice/symbol-library/] || Shark || May look like a shark fin sticking out of the water.<br />
|-<br />
| U+23E7 || <span style="font-size: xx-large;">⏧</span> || Electrical Intersection || Indicates where wires branch off || Traffic circle || Looks like a diagram of a {{w|roundabout}} as shown on road signs.<br />
|-<br />
| U+2A33 || <span style="font-size: xx-large;">⨳</span> || {{w|Smash product}} || the quotient of the underlying spaces of two {{w|pointed spaces}} where points in the {{w|product spaces}} are identified if they contain either labeled point as an element. || <div style="transform: rotate(-45deg); display: table-cell;">H</div><div style="transform: rotate(-45deg); display: table-cell;">A</div><div style="transform: rotate(-45deg); display: table-cell;">S</div><div style="transform: rotate(-45deg); display: table-cell;">H</div><div style="transform: rotate(-45deg); display: table-cell;">T</div><div style="transform: rotate(-45deg); display: table-cell;">A</div><div style="transform: rotate(-45deg); display: table-cell;">G</div> || Looks somewhat like the {{w|Number sign|hash}} symbol (#) – commonly used for indicating tags called {{w|hashtag}}s in social media, but rotated counterclockwise 45 degrees.<br />
|-<br />
| U+2A7C || <span style="font-size: xx-large;">⩼</span> || Greater-Than with Question Mark Above || Used in proofs to indicate a greater-than relation that should exist but hasn't been proven yet (non-rigorous) || Confused alligator || One metaphor used when teaching inequality signs in primary school is that the sign looks like an alligator mouth "eating" the larger number. Question marks are commonly used in cartoons to indicate confusion on the part of a character.<br />
|-<br />
| U+299E || <span style="font-size: xx-large;">⦞</span> || Angle with S Inside || Plural for the angle symbol (∠) [https://www.quora.com/Unicode-How-is-the-s-in-triangle-glyph-used-in-mathematics][https://www.birdvilleschools.net/cms/lib2/TX01000797/Centricity/Domain/1114/Homework%20Helper%20Unit%203%20ch%209-10.pdf] rarely used || Snack || May look like a mouth eating an S, where the S symbolizes some snack food.<br />
|-<br />
| U+2A04 || <span style="font-size: xx-large;">⨄</span> || {{w|Arity|N-ary}} Union Operator with Plus || Disjoint union[https://books.google.com/books?id=531cAgAAQBAJ&pg=PA165&lpg=PA165&dq=%E2%A8%84&source=bl&ots=oYXkMNXP-T&sig=ACfU3U2QvMRBkD7uVG0OSumKI0JQtjTIKA&hl=en&sa=X&ved=2ahUKEwios862ypL3AhWXVTABHTnQALQQ6AF6BAgKEAM] (joining two sets that have no elements in common) || Drink refill || Looks like a cup with a plus to indicate adding drink to the cup.<br />
|-<br />
| U+2B48 || <span style="font-size: xx-large;">⭈</span> || Rightwards Arrow Above Reverse Almost Equal To || Pairs with <span style="font-size: x-large;">⭂</span> which could conceivably mean {{w|Assignment (computer science)|assignment}} of an {{w|Approximation|approximation}}, but neither seem to be in use. || Snakes over there || Looks like two squiggles to represent snakes and an arrow indicating the direction where they may be found.<br />
|-<br />
| U+225D || <span style="font-size: xx-large;">≝</span> || Equal To By Definition || Indicates an equation where the left side is to be defined as the right side[https://www.reddit.com/r/math/comments/1z1mty/can_someone_please_explain_the_equal_to_by/] usually used in proofs to indicate a definition is being introduced|| Definitely, for sure || "Def" is a contraction of "definitely" used in slang; the equal sign looks like a double underline, indicating heavy emphasis.<br />
|-<br />
| U+237C || <span style="font-size: xx-large;">⍼</span> || Right Angle with Downwards Zigzag Arrow || No purpose is known[https://ionathan.ch/2022/04/09/angzarr.html]; speculation includes "Y axis continues downward" and "diode with a gate". || Larry Potter || Looks like the letter "L" and a lightning bolt. {{w|Harry Potter (character)|Harry Potter}} is known for having a lightning bolt-shaped scar on his forehead. The character {{w|Legal_disputes_over_the_Harry_Potter_series#Nancy_Stouffer|Larry Potter}} figured in a fraudulent legal claim against J.K. Rowling.<br />
|-<br />
| U+2A50 || <span style="font-size: xx-large;">⩐</span> || Closed Union with Serifs and Smash Product || Indicates that a collection of topological spaces is {{w|Union-closed sets conjecture|closed}} when taking arbitrary unions and smash products. That is, if you take the union of any collection of topological spaces in the collection (even uncountably many), or the smash product of them, the result will also be in that collection. This is apparently important because the sets can't be isomorphic (one cannot be rearranged to be exactly the other) [https://mathoverflow.net/questions/196084/counterexample-for-associativity-of-smash-product] For use in a serif font|| Spider caught with a cup and index card || Spiders or other bugs found within someone's house or workspace may be caught with a glass and something flat, often a card or a magazine, to be released outside. The eight projecting lines of the smash product symbol resemble the eight legs of a spider.<br />
|-<br />
| U+2A69 || <span style="font-size: xx-large;">⩩</span> || Triple Horizontal Bar with Triple Vertical Stroke || Decorative.{{citation needed}} Possibly a four-by-four {{w|tic-tac-toe}} board.[https://pages.cs.wisc.edu/~sandlund/NumericalTicTacToe.pdf] || ℍ𝕒𝕤𝕙𝕥𝕒𝕘 || Hash symbol with one extra vertical and horizontal line, or perhaps a hash symbol which has been accidentally double-struck or overprinted.<br />
|-<br />
| U+2368 || <span style="font-size: xx-large;">⍨</span> || APL Functional Symbol Tilde Diaeresis || Used for a two-argument operation to [https://aplwiki.com/wiki/Commute commute] (swap) its arguments or allow it to use a single provided argument in both argument slots, and to convert a value into a [https://aplwiki.com/wiki/Constant constant] function || <span style="font-size: large;">:/</span> || Looks like a confused or disappointed face. Randall's use is in fact common among {{w|APL (programming language)|APL}} programmers in the comments, as documented [https://aplwiki.com/wiki/APL_Orchard#Emoticons here] and [https://aplwiki.com/wiki/Humour#Glyph_puns here].<br />
|-<br />
| U+2118 || <span style="font-size: xx-large;">℘</span> || Script Capital P || An eccentric, Gothic-esque capital Roman P first used by Weierstrass for his self-named "p-function." This symbol is universally used for the {{w|Weierstrass elliptic function|p-function}} and apparently has no name except "Weierstrass-p." It is reminiscent of ∂, a stylized cursive d used for partial differentials or ∫, a stylized long s used for integrals. || Snake || This symbol coils around like a long snake, with a tapering-off tail on one end and a small "head" on the other.<br />
|-<br />
| U+2AC1 || <span style="font-size: xx-large;">⫁</span> || Subset with Multiplication Sign Below || Indicates that one set is subset of another by means of the cross product || <div style="writing-mode: vertical-rl; text-align: center;">User<br />experience</div> || Looks like the letters "Ux" sideways; Ux is a common abbreviation for {{w|user experience}}.<br />
|-<br />
| U+232D || <span style="font-size: xx-large;">⌭</span> || {{w|Cylindricity}} || A symbol used in geometric dimensioning and tolerancing (GD&T) to represent a parameter called "cylindricity" which describes the statistical deviation of an ensemble of surfaces from a reference cylinder. [https://cimquest-inc.com/metrology-minute-cylindricity/ example use] || Rolling dough between your hands to shape it into a ball || Looks like two flat hands (perhaps like stick-figure arms) rolling a ball between them. Rolling dough between one's hands to make it into a ball is an important step in making many kinds of pastry and bread.<br />
|-<br />
| U+2A13 || <span style="font-size: xx-large;">⨓</span> || Line Integration with Semicircular Path Around Pole || Very rare symbol for half of a closed {{w|Contour integration|contour}} or {{w|Line integral|line}} integral which contains the {{w|Origin (mathematics)|origin}} in its interior. Contour integrals which circle the origin are very important in complex analysis. If such an integral were split into two parts, each could be represented by this symbol.<br />
This can be mistaken for <span style="font-size: x-large;">⨔</span> (Integral not including the {{w|Zeros and poles|pole}}, which has a wider and more complete arc around an offset dot.) [https://math.stackexchange.com/questions/2299363/where-is-the-%E2%A8%93-integral-symbol-defined]<br />
|| Integral that avoids a bee on the whiteboard || Looks like an {{w|integral}} symbol with a bump that goes around a dot, as if a professor was drawing an integral on a whiteboard but did not want to disturb a bee that had landed right in the path of their marker.<br />
|-<br />
| U+2A0B (title text)|| <span style="font-size: xx-large;">⨋</span> || Summation with Integral || The sum of the sum of the discrete elements (∑) and the integrals (∫) over the connected pieces. This symbol requires context to be meaningful but could occur, for instance, when computing probabilities using mixed distributions.<br />
[https://twitter.com/fermatslibrary/status/1308743505309822977 see also] <br />
|| Mathematicians need to calm down || Since the two symbols combined are kinds of summation the symbol may seem unnecessary at first glance. The comment given may make fun of mathematicians' tendency to form increasingly complex expressions in their work.<br />
|-<br />
|}<br />
<br />
This comic may have been inspired by [https://ionathan.ch/2022/04/09/angzarr.html this blog post], which went viral (in a limited sense) the same day the comic was published.<br />
<br />
==Transcript==<br />
<br />
[Title:] Weird Unicode math symbols<br />
<br />
[Subtitle:] And their meanings<br />
<br />
{|<br />
| U+29CD || ⧍ || Shark<br />
|-<br />
| U+23E7 || ⏧ || Traffic circle<br />
|-<br />
| U+2A33 || ⨳ || Hashtag [the text is slanted counterclockwise]<br />
|-<br />
| U+299E || ⦞ || Snack<br />
|-<br />
| U+2A04 || ⨄ || Drink refill<br />
|-<br />
| U+2B48 || ⭈ || Snakes over there<br />
|-<br />
| U+225D || ≝ || Definitely, for sure<br />
|-<br />
| U+237C || ⍼ || Larry Potter<br />
|-<br />
| U+2A50 || ⩐ || Spider caught with a cup and index card<br />
|-<br />
| U+2A69 || ⩩ || [The word "hashtag" but with extra horizontal and vertical lines]<br />
|-<br />
| U+2368 || ⍨ || :/<br />
|-<br />
| U+2118 || ℘ || Snake<br />
|-<br />
| U+2AC1 || ⫁ || [The words "user experience" rotated clockwise 90 degrees]<br />
|-<br />
| U+232D || ⌭ || Rolling dough between your hands to shape it into a ball<br />
|-<br />
| U+2A13 || ⨓ || Integral that avoids a bee on the whiteboard<br />
|}<br />
<br />
{{comic discussion}}<br />
[[Category:Unicode]]<br />
[[Category:Math]]<br />
[[Category:Harry Potter]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2591:_Qua&diff=228464Talk:2591: Qua2022-03-15T13:47:14Z<p>172.70.34.91: Waiting for Godot: pls no</p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
As i've never seen anyone use this, we can safely assume that exterminating these people would not affect the world one bit [[Special:Contributions/162.158.191.131|162.158.191.131]] 10:39, 10 March 2022 (UTC)<br />
<br />
If Megan's not careful, this pattern can quickly spiral to infinity: "Nice use of qua qua qua ''qua'' qua qua qua." "Nice use of qua qua qua qua qua qua qua ''qua'' qua qua qua qua qua qua qua." "Nice use of..." --mezimm [[Special:Contributions/172.70.178.93|172.70.178.93]] 16:37, 9 March 2022 (UTC)<br />
:Or perhaps "Nice use of 'Nice use of ... '" although new forms of quote mark would need to be invented. --[[User:192·168·0·1|192·168·0·1]] ([[User talk:192·168·0·1|talk]]) 19:11, 9 March 2022 (UTC)<br />
::From what I've seen, you just alternate between " and '. [[Special:Contributions/172.70.126.65|172.70.126.65]] 23:45, 9 March 2022 (UTC)<br />
:Hey, [[244|no recursing]]. [[User:Ruffy314|Ruffy314]] ([[User talk:Ruffy314|talk]]) 21:46, 9 March 2022 (UTC)<br />
'''qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua''' [[User:New editor|New editor]] ([[User talk:New editor|talk]]) 20:37, 9 March 2022 (UTC)<br />
:eh, close enough.[[User:Lettherebedarklight|youtube.com/watch?v&#61;miLcaqq2Zpk]] ([[User talk:Lettherebedarklight|talk]]) 12:55, 10 March 2022 (UTC)<br />
<br />
I feel like there should be a duck somewhere. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:05, 9 March 2022 (UTC)<br />
Buffalo everywhere are concerned.<br />
<br />
Maybe one could note that the two uses of "qua" are different: While in the meaning of "as"/"in capacity of", qua is a preposition, it is a relative pronoun in the Latin expression "sine qua non". <br />
So, actually, the explanation of the title text given so far is slightly incorrect: The correct use of "qua" (as a preposition) is NOT essential to the correct use of "sine qua non" (where we use only the Latin relative pronoun). Instead, "qua" is essential to build the complex expression "sine qua non qua sine qua non", where the middle qua is indeed the preposition! <br />
I also feel that Randall is making fun of "pretentious" people by demonstrating how quickly their talk turns into something like "blablabla" [[Special:Contributions/172.70.246.153|172.70.246.153]] 21:51, 9 March 2022 (UTC)<br />
<br />
:But the explanation of the title text is not claiming that it is specifically as a proposition that “qua” is essential, is it?<br />
:[[User:While False|While False]] ([[User talk:While False|talk]]) 04:31, 10 March 2022 (UTC)<br />
<br />
:: Well, basically, you're right. But to clarify it better, you would at least have to point out that the title text is talking of two different "qua"s then, BOTH the preposition and the relative pronoun. And in order to use them correctly, you ought to differentiate between the both, i.m.h.o. [[Special:Contributions/162.158.90.171|162.158.90.171]] 07:38, 10 March 2022 (UTC)<br />
<br />
:::I agree with you.<br />
<br />
:::[[User:While False|While False]] ([[User talk:While False|talk]]) 08:22, 10 March 2022 (UTC)<br />
<br />
<br />
Even after reading the comic, title text & the explainxkcd.com description, I am still confused. I've never heard of that word/phrase.<br />
<br />
:Agreed, I feel that the explanation qua it stands leaves me almost qua confused qua I was before coming here and reading it. If qua roughly means “as” or “for the purpose of” then would someone please explain why this not an example of someone using sine qua non: “I could have left work after the accident if I wanted, but decided sine, bore the pain, and stayed.” I don’t get it.[[Special:Contributions/172.70.131.214|172.70.131.214]] 06:47, 10 March 2022 (UTC)<br />
<br />
:Yeah, it's only really familiar to people who speak Higher Academic. I think at least three nines of all uses of the word "qua" in English-language writing are in the phrase "sine qua non", which is itself too prolix to really qualify as common. The main thing that saves "sine qua non" from being jargon, is that it's not in any way discipline-specific. It's as likely to show up in a formal academic paper related to algebraic topology, as it is to show up in a formal academic paper related to medieval literature. This puts it into the same general category as e.g. "albeit", "je ne sais quoi", or "prolix". As for uses of the word "qua" outside the context of the phrase "sine qua non", I believe this may be the first I've ever encountered, so it's difficult to generalize. --Jonadab (not logged in).<br />
<br />
On this you are not alone.<br />
<br />
If you say "Qua Qua Qua Qua" really fast, it kind of sounds like you are saying "quack quack quack". Thus Megan would sound like she is saying "Nice use of quack quack quack quack..." [[Special:Contributions/162.158.107.230|162.158.107.230]] 00:56, 10 March 2022 (UTC)<br />
<br />
: “Qua qua qua” is how in Italian you write the duck sound. [[User:Vdm|Vdm]] ([[User talk:Vdm|talk]]) 21:23, 11 March 2022 (UTC)<br />
<br />
This comic is most likely inspired by this week's Sunday puzzle on NPR, which asks for an English word that starts with the "kw" sound but doesn't contain Q,U,K, or W. See https://www.npr.org/2022/03/06/1084744124/sunday-puzzle-may-the-odds-be-in-your-favor<br />
:Well, apart from the u...[[Special:Contributions/172.69.79.153|172.69.79.153]] 17:19, 10 March 2022 (UTC)<br />
:My answer to the puzzle is "choir" [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 20:20, 10 March 2022 (UTC)<br />
<br />
Quamvis sint sub aqua sub aqua maledicere temptant. Sebastian --[[Special:Contributions/172.70.251.88|172.70.251.88]] 06:22, 10 March 2022 (UTC)<br />
<br />
Randall is not using qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua, he's using it to sound funny and play with words. [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 07:24, 10 March 2022 (UTC)<br />
<br />
:I think Randall is just trying to sound pretentious coûte que coûte ;-P --[[User:IByte|IByte]] ([[User talk:IByte|talk]]) 10:33, 10 March 2022 (UTC)<br />
<br />
No reference here to Waiting for Godot?<br />
<br />
:People only reference Waiting for Godot in order to sound pretentious. Nobody has ever actually read it.<br />
<br />
I am anxiously awaiting the day when I come to explainxkcd and the content for that day's comic is just "...look, I don't know man"<br />
:Yes. and I am waiting for someone to answer, "...it's just funnier that way." [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 20:20, 10 March 2022 (UTC)<br />
<br />
Perhaps it would help to explain to use angle brackets:<br />
- Cueball: <qua> qua <qua> ''("qua-word" _used for_ "qua-meaning"), but also ("any word/expression" _used for_ "its own meaning") with the two outer "qua" = abbreviation of "aliqua" in the meaning of "something"''<br />
- Megan: <<qua> qua <qua>> qua <<qua> qua <qua>> ''("qua qua qua"-wording _used for_ "qua qua qua"-meaning)''<br />
- Title Text: <Qua> qua <qua> is the <sine qua non> of <<sine qua non> qua <sine qua non>> ''"qua qua qua"-meaning/construct is the _indispensable essence_ of "sine qua non"-wording _used for_ "sine-qua-non"-meaning''<br />
Sebastian --[[Special:Contributions/172.70.242.207|172.70.242.207]] 06:02, 11 March 2022 (UTC)<br />
<br />
I have trouble reading the word <code>qua</code>, my brain seems to automatically reorient it, so I can comfortably read <code>end</code>. --[[Special:Contributions/162.158.92.193|162.158.92.193]] 17:44, 12 March 2022 (UTC)<br />
<br />
I am guessing that "Badger badger Badger badger badger badger Badger badger" is just as valid as "Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo"? [[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]]) 00:54, 14 March 2022 (UTC)<br />
: No, because the plural of "badger" is "badgers", not "badger". Also "Badger" isn't a well-known city, if it is indeed a place. [[Special:Contributions/172.70.130.153|172.70.130.153]] 05:34, 15 March 2022 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2591:_Qua&diff=228463Talk:2591: Qua2022-03-15T13:38:46Z<p>172.70.34.91: Higher Academic</p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
As i've never seen anyone use this, we can safely assume that exterminating these people would not affect the world one bit [[Special:Contributions/162.158.191.131|162.158.191.131]] 10:39, 10 March 2022 (UTC)<br />
<br />
If Megan's not careful, this pattern can quickly spiral to infinity: "Nice use of qua qua qua ''qua'' qua qua qua." "Nice use of qua qua qua qua qua qua qua ''qua'' qua qua qua qua qua qua qua." "Nice use of..." --mezimm [[Special:Contributions/172.70.178.93|172.70.178.93]] 16:37, 9 March 2022 (UTC)<br />
:Or perhaps "Nice use of 'Nice use of ... '" although new forms of quote mark would need to be invented. --[[User:192·168·0·1|192·168·0·1]] ([[User talk:192·168·0·1|talk]]) 19:11, 9 March 2022 (UTC)<br />
::From what I've seen, you just alternate between " and '. [[Special:Contributions/172.70.126.65|172.70.126.65]] 23:45, 9 March 2022 (UTC)<br />
:Hey, [[244|no recursing]]. [[User:Ruffy314|Ruffy314]] ([[User talk:Ruffy314|talk]]) 21:46, 9 March 2022 (UTC)<br />
'''qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua''' [[User:New editor|New editor]] ([[User talk:New editor|talk]]) 20:37, 9 March 2022 (UTC)<br />
:eh, close enough.[[User:Lettherebedarklight|youtube.com/watch?v&#61;miLcaqq2Zpk]] ([[User talk:Lettherebedarklight|talk]]) 12:55, 10 March 2022 (UTC)<br />
<br />
I feel like there should be a duck somewhere. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:05, 9 March 2022 (UTC)<br />
Buffalo everywhere are concerned.<br />
<br />
Maybe one could note that the two uses of "qua" are different: While in the meaning of "as"/"in capacity of", qua is a preposition, it is a relative pronoun in the Latin expression "sine qua non". <br />
So, actually, the explanation of the title text given so far is slightly incorrect: The correct use of "qua" (as a preposition) is NOT essential to the correct use of "sine qua non" (where we use only the Latin relative pronoun). Instead, "qua" is essential to build the complex expression "sine qua non qua sine qua non", where the middle qua is indeed the preposition! <br />
I also feel that Randall is making fun of "pretentious" people by demonstrating how quickly their talk turns into something like "blablabla" [[Special:Contributions/172.70.246.153|172.70.246.153]] 21:51, 9 March 2022 (UTC)<br />
<br />
:But the explanation of the title text is not claiming that it is specifically as a proposition that “qua” is essential, is it?<br />
:[[User:While False|While False]] ([[User talk:While False|talk]]) 04:31, 10 March 2022 (UTC)<br />
<br />
:: Well, basically, you're right. But to clarify it better, you would at least have to point out that the title text is talking of two different "qua"s then, BOTH the preposition and the relative pronoun. And in order to use them correctly, you ought to differentiate between the both, i.m.h.o. [[Special:Contributions/162.158.90.171|162.158.90.171]] 07:38, 10 March 2022 (UTC)<br />
<br />
:::I agree with you.<br />
<br />
:::[[User:While False|While False]] ([[User talk:While False|talk]]) 08:22, 10 March 2022 (UTC)<br />
<br />
<br />
Even after reading the comic, title text & the explainxkcd.com description, I am still confused. I've never heard of that word/phrase.<br />
<br />
:Agreed, I feel that the explanation qua it stands leaves me almost qua confused qua I was before coming here and reading it. If qua roughly means “as” or “for the purpose of” then would someone please explain why this not an example of someone using sine qua non: “I could have left work after the accident if I wanted, but decided sine, bore the pain, and stayed.” I don’t get it.[[Special:Contributions/172.70.131.214|172.70.131.214]] 06:47, 10 March 2022 (UTC)<br />
<br />
:Yeah, it's only really familiar to people who speak Higher Academic. I think at least three nines of all uses of the word "qua" in English-language writing are in the phrase "sine qua non", which is itself too prolix to really qualify as common. The main thing that saves "sine qua non" from being jargon, is that it's not in any way discipline-specific. It's as likely to show up in a formal academic paper related to algebraic topology, as it is to show up in a formal academic paper related to medieval literature. This puts it into the same general category as e.g. "albeit", "je ne sais quoi", or "prolix". As for uses of the word "qua" outside the context of the phrase "sine qua non", I believe this may be the first I've ever encountered, so it's difficult to generalize. --Jonadab (not logged in).<br />
<br />
On this you are not alone.<br />
<br />
If you say "Qua Qua Qua Qua" really fast, it kind of sounds like you are saying "quack quack quack". Thus Megan would sound like she is saying "Nice use of quack quack quack quack..." [[Special:Contributions/162.158.107.230|162.158.107.230]] 00:56, 10 March 2022 (UTC)<br />
<br />
: “Qua qua qua” is how in Italian you write the duck sound. [[User:Vdm|Vdm]] ([[User talk:Vdm|talk]]) 21:23, 11 March 2022 (UTC)<br />
<br />
This comic is most likely inspired by this week's Sunday puzzle on NPR, which asks for an English word that starts with the "kw" sound but doesn't contain Q,U,K, or W. See https://www.npr.org/2022/03/06/1084744124/sunday-puzzle-may-the-odds-be-in-your-favor<br />
:Well, apart from the u...[[Special:Contributions/172.69.79.153|172.69.79.153]] 17:19, 10 March 2022 (UTC)<br />
:My answer to the puzzle is "choir" [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 20:20, 10 March 2022 (UTC)<br />
<br />
Quamvis sint sub aqua sub aqua maledicere temptant. Sebastian --[[Special:Contributions/172.70.251.88|172.70.251.88]] 06:22, 10 March 2022 (UTC)<br />
<br />
Randall is not using qua qua qua qua qua qua qua qua qua qua qua qua qua qua qua, he's using it to sound funny and play with words. [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 07:24, 10 March 2022 (UTC)<br />
<br />
:I think Randall is just trying to sound pretentious coûte que coûte ;-P --[[User:IByte|IByte]] ([[User talk:IByte|talk]]) 10:33, 10 March 2022 (UTC)<br />
<br />
No reference here to Waiting for Godot?<br />
<br />
I am anxiously awaiting the day when I come to explainxkcd and the content for that day's comic is just "...look, I don't know man"<br />
:Yes. and I am waiting for someone to answer, "...it's just funnier that way." [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 20:20, 10 March 2022 (UTC)<br />
<br />
Perhaps it would help to explain to use angle brackets:<br />
- Cueball: <qua> qua <qua> ''("qua-word" _used for_ "qua-meaning"), but also ("any word/expression" _used for_ "its own meaning") with the two outer "qua" = abbreviation of "aliqua" in the meaning of "something"''<br />
- Megan: <<qua> qua <qua>> qua <<qua> qua <qua>> ''("qua qua qua"-wording _used for_ "qua qua qua"-meaning)''<br />
- Title Text: <Qua> qua <qua> is the <sine qua non> of <<sine qua non> qua <sine qua non>> ''"qua qua qua"-meaning/construct is the _indispensable essence_ of "sine qua non"-wording _used for_ "sine-qua-non"-meaning''<br />
Sebastian --[[Special:Contributions/172.70.242.207|172.70.242.207]] 06:02, 11 March 2022 (UTC)<br />
<br />
I have trouble reading the word <code>qua</code>, my brain seems to automatically reorient it, so I can comfortably read <code>end</code>. --[[Special:Contributions/162.158.92.193|162.158.92.193]] 17:44, 12 March 2022 (UTC)<br />
<br />
I am guessing that "Badger badger Badger badger badger badger Badger badger" is just as valid as "Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo"? [[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]]) 00:54, 14 March 2022 (UTC)<br />
: No, because the plural of "badger" is "badgers", not "badger". Also "Badger" isn't a well-known city, if it is indeed a place. [[Special:Contributions/172.70.130.153|172.70.130.153]] 05:34, 15 March 2022 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2586:_Greek_Letters&diff=2276912586: Greek Letters2022-02-27T20:41:41Z<p>172.70.34.91: </p>
<hr />
<div>{{comic<br />
| number = 2586<br />
| date = February 25, 2022<br />
| title = Greek Letters<br />
| image = greek_letters.png<br />
| titletext = If you ever see someone using a capital xi in an equation, just observe them quietly to learn as much as you can before they return to their home planet.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by '''''O R B S''''' PRO®- Missing explanations for some letters. The text for each letter should be in the explanation with an attempt at explaining it. This has not been included and many of the letters have no explanation of the given text, only for what they actually are used for. Do NOT delete this tag too soon.}}<br />
Mathematics uses lots of Greek letters, typically using {{w|Greek_letters_used_in_mathematics,_science,_and_engineering|the same letter consistently}} to represent a particular constant or type of variable. This comic gives a (non-)explanation of what they typically mean, see [[#Greek letters|below]].<br />
<br />
In the title text the joke about capital Xi from the main comic is continued. In the main comic those using Ξ (capital xi) greets us as Earth mathematicians, indicating they are not from Earth, but have come here to learn what we know of math. In the title text the idea that any one using Ξ must be aliens is made clear. So if you ever meet someone using this letter while doing math, then learn as much as you can be quietly observing them, before they return to their home planet. Either learn from their possible advanced math (that allowed them to construct a way to get from one star system to another), or learn about them as the aliens species they represent.<br />
<br />
Previously [[Randall]] made a similar comic, [[2520: Symbols]], about math symbols.<br />
<br />
===Greek letters===<br />
<br />
* '''π (lower-case pi)''' — Typically used to refer to the constant ratio between a circle’s circumference and its diameter (approximately 3.14). This usage of pi commonly applies to equations in introductory geometry classes, which would be considered "simple" by advanced mathematicians. However, pi also shows up seemingly randomly in extremely advanced and complicated equations (that have nothing to do with a circle), as part of the solution to an infinite series or whatnot. (There are also {{w|Pi_(letter)#Lowercase_Pi|several advanced equations}} which use pi to represent variables other than the ratio of the circumference to the diameter.)<br />
<br />
* '''Δ (capital delta)''' — Typically used to refer to a change in quantity.<br />
<br />
* '''δ (lower-case delta)''' — Also typically used to refer to a change in quantity, but unlike the capital delta, this is only for infinitesimal changes and is used in derivative and integration expressions in mathematics hence the text's reference to "a mathematician's fault".<br />
<br />
* '''θ (lower-case theta)''' — Typically used to refer to an angle, and is notably used in the polar coordinate system. The text refers to its close relationship with circles, on which the polar coordinate system is based.<br />
<br />
* '''ϕ (lower-case phi)''' — Typically used to refer to another angle other than one referred to by theta. It's used in spherical coordinates, and the text refers to how spheres, or orbs, are important in spherical coordinates. <br />
<br />
* '''ϵ (lower-case epsilon)''' — Epsilon is typically used to refer to very small quantities which go to zero in the limit. In this interpretation, the comic suggests that because these quantities are very small, they are unimportant, when in reality the study of quantities that go to zero gives rise to limits and calculus. Also used for the series of transfinite numbers that are unreachable from ω (see below) using addition, multiplication, and exponentiation, and in statistical modelling to denote observational noise. <br />
<br />
* '''υ,ν (lower-case upsilon and lower-case nu)''' — Common in college level physics and engineering equations.<br />
<br />
* '''μ (lower-case mu)''' — Among other things, mathematicians use ''μ'' in category theory, measure theory, and as the symbol for the Ramanujan–Soldner constant, all uses with highly abstract applications. Physicists use latin letters for the indices of the 3-vectors of classical physics and greek indices for the 4-vectors of special relativity. This leads to ''μ'' being ubiquitous in a field which is very far from everyday experience (where speeds approach the speed of light). It is, however, also employed in statistics for the mean of a population, and in various fields of classical physics, e.g. as the symbol for the coefficient of friction, both concepts that most people are well acquainted with empirically if not formally. Another common use of ''μ'' – outside of equations – is the symbol of the SI prefix ''micro-''.<br />
<br />
* '''Σ (capital sigma)''' — Typically used as a symbol for summation of a series of numbers.<br />
<br />
* '''Π (capital pi)''' — Typically used as a symbol for multiplication of a series of numbers.<br />
<br />
* '''ζ (lower-case zeta)''' — Frequently used with number theory, in particular the {{w|Riemann zeta function}}, which is a the focus of a famously unsolved problem in highly advanced mathematics.<br />
<br />
* '''β (lower-case beta)''' — This could be a reference to the typical usage of beta to represent coefficients of independent variables in the {{w|Ordinary_least_squares#Linear_model|ordinary least squares regression model}}. Regression can potentially have a large number of independent variables, hence potentially many different betas (differentiated by subscript, or compacted into matrix notation) would be used. Alternatively, the comic might suggest whatever source this equation is from has run out of Latin letters to use as symbols, and is now going through the Greek letters.<br />
<br />
* '''α (lower-case alpha)''' — Typically used to represent the probability of a Type-I error (false positive) occurring in a hypothesis test. It could also possibly refer to the {{w|fine-structure constant}} which shows up in high energy physics, atomic physics, quantum electrodynamics, and at least [[1047|one other xkcd comic]]. Alpha could also refer to {{w|angular acceleration}}, or the acceleration of spinning systems, which are capable of killing people in a number of [[123|interesting ways]]. Another dangerous annotation of α comes from ionising α-radiation: while it can be easily blocked by even a sheet of paper, it has been {{W|Alexander Litvinenko#Poisoning and death|used for assassinations}} through ingestion.<br />
<br />
* '''Ω (capital omega)''' — Omega is the last letter of the Greek alphabet, and thus often seen as momentous (the end, the final word, death). This symbol has been used for a {{w|Omega_function|variety of mathematical functions}} and as the symbol for the {{w|first uncountable ordinal}}. Commonly used – outside of equations – as the symbol for {{w|ohms}}, a unit for electrical resistance. <br />
<br />
* '''ω (lower-case omega)''' — Lower-case omega is used for the {{w|Transfinite_number|lowest transfinite ordinal number}}, a specific way of referring to a type of infinity in a mathematically robust way. The line about dying here among the transfinite equations may be in reference to the literally infinite scope of the branch of mathematics. It is also used in physics and electrical engineering for angular velocity, equal to 2πf.<br />
<br />
* '''σ (lower-case sigma)''' — In statistics, commonly refers to the standard deviation of a distribution. Statistics often attempts to use simplified models to explain real-world phenomena.<br />
<br />
* '''ξ (lower-case xi)''' — Randall comments that this looks like a strand of curly hair. Xi is used in the {{w|Riemann Xi function}}. <br />
<br />
* '''γ (lower-case gamma)''' — Used for the Lorentz factor, an important variable in special relativity calculations. Its use implies that you are dealing with speeds approaching the speed of light, and therefore with spaceships or other moving objects not confined to Earth. <br />
<br />
* '''ρ (lower-case rho)''' — often used to measure density, such as air density that a wing might be travelling through.<br />
<br />
* '''Ξ (capital xi)''' — Resembles the icon of some {{w|Stack Exchange}} [https://stackexchange.com/sites# sites]. This character is also looks similar to Besh, the second letter of the {{w|Aurebesh}} alphabet [https://starwars.fandom.com/wiki/Aurebesh] used in ''Star Wars.'' According to the comic, anyone using this letter is likely a being from another planet. This is probably because capital xi is rarely used and is not standard notation for any common equations.<br />
<br />
* '''ψ (lower-case psi)''' — Psi looks exactly like a trident. In quantum mechanics it's used to describe the wave function of a particle, leading to a bad pun. (Psi is also used in mathematics to represent the sum of the inverse of the Fibonacci numbers, the division polynomials, and the supergolden ratio.)<br />
<br />
==Transcript==<br />
:[A list with 21 explanations of different Greek letters. To the left the letter (on in one case two letters) are shown, and then the explanation is written to the right in one or two lines (and in one case on three lines). Above these explanations there is a header in a slightly larger font:]<br />
:<big>What Greek letters mean in equations</big><br />
:π This math is either very simple or impossible.<br />
:Δ Something has changed.<br />
:δ Something has changed and it's a mathematician's fault.<br />
:θ Circles!<br />
:Φ '''''Orbs'''''<br />
:ϵ Not important, don't worry about it.<br />
:υ,ν Is that a v or a u? Or...oh no, it's one of ''those''.<br />
:μ This math is cool but it's not about anything that you will ever see or touch, so whatever.<br />
:Σ Thank you for purchasing ''Addition Pro''®!<br />
:Π ...and the ''Multiplication''® expansion pack!<br />
:ζ This math will only lead to more math.<br />
:β There are just too many coefficients.<br />
:α Oh boy, now '''''this''''' is math about something real. This is math that could '''''kill''''' someone.<br />
:Ω Oooh, ''some'' mathematician thinks their function is cool and important.<br />
:ω A lot of work went into these equations and you are going to die here among them.<br />
:σ Some poor soul is trying to apply this math to real life and it's not working.<br />
:ξ Either this is terrifying mathematics or there was a hair on the scanned page.<br />
:γ ''Zoom'' pew pew pew [space noises] ''zoooom!''<br />
:ρ Unfortunately, the test vehicle suffered an unexpected wing separation event.<br />
:Ξ Greetings! We hope to learn a great deal by exchanging knowledge with your Earth mathematicians.<br />
:ψ You have entered the domain of King Triton, ruler of the waves.<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Math]]<br />
[[Category:Aliens]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2580:_Rest_and_Fluids&diff=2269222580: Rest and Fluids2022-02-11T23:54:29Z<p>172.70.34.91: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 2580<br />
| date = February 11, 2022<br />
| title = Rest and Fluids<br />
| image = rest_and_fluids.png<br />
| titletext = Remember not to take it easy. Put a hot washcloth on your forehead, remain standing, and breathe dry air while taking lots of histamines. You need to give your body a chance to get sick again.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a DEHYDRATED EDITOR - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
[[Black Hat]] congratulates [[Cueball]] on his recovery from some type of sickness. Common advice when someone is sick is to get plenty of rest and drink lots of water. However, being Black Hat, he suggests that since Cueball is getting better that he should do the opposite of this, which is to stop drinking water and engage in a lot of activity — in this case, by running on a {{w|treadmill}}. The caption explains this, saying that it is "important" to tell people who have recently recovered from sickness to stop resting and drinking fluids. Obviously, because {{w|dehydration}} and over-exerting yourself is bad,{{Citation needed}} people should not take this advice. <br />
<br />
The title-text expands on this backward line of thinking by suggesting to do the opposite of common cold/flu remedies: breathe dry air, stand, take {{w|histamines}} (as opposed to {{w|antihistamine}}s), etc., with the aim of getting sick again. Needless to say, this is the opposite of what most people want to achieve with their health. {{Citation needed}}<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
:[Cueball and Black Hat are standing and talking to each other.]<br />
:Black Hat: So glad you're feeling better!<br />
:Black Hat: Be sure to get dehydrated and run on a treadmill until you black out!<br />
<br />
:[Caption below the panel]<br />
:Once people aren't sick anymore, it's important to remind them to stop resting and drinking fluids.<br />
{{comic discussion}}<br />
[[Category:Comics featuring Black Hat]]<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Biology]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2577:_Sea_Chase&diff=2266532577: Sea Chase2022-02-06T18:09:50Z<p>172.70.34.91: </p>
<hr />
<div>{{comic<br />
| number = 2577<br />
| date = February 4, 2022<br />
| title = Sea Chase<br />
| image = sea_chase.png<br />
| titletext = There are two rules on this ship: Never gaze back into the projection abyss, and never touch the red button labeled DYMAXION.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a STRETCHED OBLONG PARABOLOID. Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
In this comic, Randall returns to one of his pet subjects: [[977: Map Projections|map projections]]. Unusually, this time it is from the perspective of people living - or, in this case, sailing - upon the world that is quite literally being mapped.<br />
<br />
Two sailing ships, of circa 18th century design, are engaged in a close chase across the {{w|Atlantic}}, the aggressor flying the Skull and Crossbones of a stereotypical pirate vessel. It can be seen from the flags of both ships that they are tacking into the wind, the trailing ship seeming to be lighter and yet deploying more effective canvas with two active sails than the forward one can with three. The ship being chased has a plan to escape. And the means to do so. At a crucial moment, [[Cueball]] is told to flip a large incongruous switch that (like several [[1620: Christmas Settings|other]] [[1763: Catcalling|artifacts]] in the xkcd universe) alters the nature of their reality.<br />
<br />
Whereas beforehand the world is directly represented upon a simply contiguous map, the {{w|Robinson projection}}, it is now changed to one (which is actually the new reality) known as {{w|Goode homolosine projection|Goode Homolosine}} in which the flattening of the world mitigates localised warping of angle/distance/area by introducing discontinuities in relatively 'unused' parts of the mapped world, such as the center of the Atlantic.<br />
<br />
By precisely timing the change (as they cross a particular {{w|meridian}}, possibly the 40°W one), they leave the pursuer now on the wrong side of the very real gap, allowing the pursued ship to escape whatever fate they were trying to avoid. Though there is still an oceanic connection, it requires sailing down the edge towards the tropics, rounding this particular rent in the planet's surface and heading back up the other side. This is vastly further than Cueball's ship needs to travel to reach (presumably) any European port in which they can safely moor.<br />
<br />
The title text elaborates on the policies of the ship: crewmates are never to look into the "projection abyss" and to never hit the red button labeled "DYMAXION."<br />
<br />
The first rule suggests that changing the projection of physical reality produces a gap in reality, a void. This may be dangerous to gaze into or simply unnerving to crewmates, hence the rule. This may also be a reference to a well known quote by philosopher {{w|Friedrich Nietzsche}}: “He who fights with monsters must take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you.” See [https://www.gutenberg.org/files/4363/4363-h/4363-h.htm Beyond Good and Evil at Project Gutenberg]<br />
<br />
The second rule references a button that seems to do the same thing as the lever but changes the world into a "Dymaxion" (a {{w|Portmanteau|portmanteau}} of "dynamic", "maximum" and "tension") projection. The {{w|Dymaxion map|Dymaxion projection}} projects the Earth in a way that preserves land scale as much as possible. (Most maps warp land area, distance, and/or angle.) However, the preservation of scale comes at the cost of dramatically altering a map in a nearly unrecognizable and unintuitive manner. The necessary discontinuities resulting from pressing this button would be even more strange and mind-bending than the 'interrupted' Goode Homolosine, so turning the world into this projection may be bad, and a good reason to create a rule against pressing the button in question.<br />
<br />
The Robinson, Goode Homolosine, and Dymaxion projections have been referenced in [[977: Map Projections]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
:[A pirate ship flying the Skull and Crossbones is sailing after a merchant ship.]<br />
:Merchant ship sailor #1: They're closing in!<br />
:Merchant ship sailor #2: Hang on, we're almost at the meridian!<br />
<br />
:[A map of the Earth in the Robinson projection, with two red dots in the middle of the Atlantic Ocean. A voice comes from the red dot further to the east.]<br />
:Merchant ship sailor #2: ''Now!'' Throw the switch!<br />
<br />
:[Cueball, representing merchant ship sailor #1, pulls down a giant lever switch labeled "Projection", from "Robinson" to "Goode Homolosine".]<br />
<br />
:[A map of the Earth in the Goode Homolosine projection, with one red dot on the American side of the split and one red dot on the European side of the split.]<br />
<br />
{{comic discussion}}<br />
<br />
<br />
[[Category:Maps]]<br />
[[Category:Comics featuring Cueball]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2577:_Sea_Chase&diff=2266522577: Sea Chase2022-02-06T18:09:38Z<p>172.70.34.91: </p>
<hr />
<div>{{comic<br />
| number = 2577<br />
| date = February 4, 2022<br />
| title = Sea Chase<br />
| image = sea_chase.png<br />
| titletext = There are two rules on this ship: Never gaze back into the projection abyss, and never touch the red button labeled DYMAXION.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a STRETCHED OBLONG PARABOLOID Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
In this comic, Randall returns to one of his pet subjects: [[977: Map Projections|map projections]]. Unusually, this time it is from the perspective of people living - or, in this case, sailing - upon the world that is quite literally being mapped.<br />
<br />
Two sailing ships, of circa 18th century design, are engaged in a close chase across the {{w|Atlantic}}, the aggressor flying the Skull and Crossbones of a stereotypical pirate vessel. It can be seen from the flags of both ships that they are tacking into the wind, the trailing ship seeming to be lighter and yet deploying more effective canvas with two active sails than the forward one can with three. The ship being chased has a plan to escape. And the means to do so. At a crucial moment, [[Cueball]] is told to flip a large incongruous switch that (like several [[1620: Christmas Settings|other]] [[1763: Catcalling|artifacts]] in the xkcd universe) alters the nature of their reality.<br />
<br />
Whereas beforehand the world is directly represented upon a simply contiguous map, the {{w|Robinson projection}}, it is now changed to one (which is actually the new reality) known as {{w|Goode homolosine projection|Goode Homolosine}} in which the flattening of the world mitigates localised warping of angle/distance/area by introducing discontinuities in relatively 'unused' parts of the mapped world, such as the center of the Atlantic.<br />
<br />
By precisely timing the change (as they cross a particular {{w|meridian}}, possibly the 40°W one), they leave the pursuer now on the wrong side of the very real gap, allowing the pursued ship to escape whatever fate they were trying to avoid. Though there is still an oceanic connection, it requires sailing down the edge towards the tropics, rounding this particular rent in the planet's surface and heading back up the other side. This is vastly further than Cueball's ship needs to travel to reach (presumably) any European port in which they can safely moor.<br />
<br />
The title text elaborates on the policies of the ship: crewmates are never to look into the "projection abyss" and to never hit the red button labeled "DYMAXION."<br />
<br />
The first rule suggests that changing the projection of physical reality produces a gap in reality, a void. This may be dangerous to gaze into or simply unnerving to crewmates, hence the rule. This may also be a reference to a well known quote by philosopher {{w|Friedrich Nietzsche}}: “He who fights with monsters must take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you.” See [https://www.gutenberg.org/files/4363/4363-h/4363-h.htm Beyond Good and Evil at Project Gutenberg]<br />
<br />
The second rule references a button that seems to do the same thing as the lever but changes the world into a "Dymaxion" (a {{w|Portmanteau|portmanteau}} of "dynamic", "maximum" and "tension") projection. The {{w|Dymaxion map|Dymaxion projection}} projects the Earth in a way that preserves land scale as much as possible. (Most maps warp land area, distance, and/or angle.) However, the preservation of scale comes at the cost of dramatically altering a map in a nearly unrecognizable and unintuitive manner. The necessary discontinuities resulting from pressing this button would be even more strange and mind-bending than the 'interrupted' Goode Homolosine, so turning the world into this projection may be bad, and a good reason to create a rule against pressing the button in question.<br />
<br />
The Robinson, Goode Homolosine, and Dymaxion projections have been referenced in [[977: Map Projections]].<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
:[A pirate ship flying the Skull and Crossbones is sailing after a merchant ship.]<br />
:Merchant ship sailor #1: They're closing in!<br />
:Merchant ship sailor #2: Hang on, we're almost at the meridian!<br />
<br />
:[A map of the Earth in the Robinson projection, with two red dots in the middle of the Atlantic Ocean. A voice comes from the red dot further to the east.]<br />
:Merchant ship sailor #2: ''Now!'' Throw the switch!<br />
<br />
:[Cueball, representing merchant ship sailor #1, pulls down a giant lever switch labeled "Projection", from "Robinson" to "Goode Homolosine".]<br />
<br />
:[A map of the Earth in the Goode Homolosine projection, with one red dot on the American side of the split and one red dot on the European side of the split.]<br />
<br />
{{comic discussion}}<br />
<br />
<br />
[[Category:Maps]]<br />
[[Category:Comics featuring Cueball]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2574:_Autoresponder&diff=2259432574: Autoresponder2022-01-29T12:47:17Z<p>172.70.34.91: /* Explanation */ Added link</p>
<hr />
<div>{{comic<br />
| number = 2574<br />
| date = January 28, 2022<br />
| title = Autoresponder<br />
| image = autoresponder.png<br />
| titletext = I ADMIRE HOW YOU SET BOUNDARIES AND I HOPE YOUR COLLEAGUES RESPECT THEM! PLEASE SPARE MY LIFE!<br />
}}<br />
*This was the ninth comic to come out after the [[Countdown in header text]] started.<br />
<br />
==Explanation==<br />
{{incomplete|Created by a VERRY AGRESSIVE AUTORESPONDER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
[[Cueball]] and [[White Hat]] are going to some kind of show (a movie or concert, perhaps), and Cueball asks White Hat if he is ready to go, who affirms this but asks for Cueball to email him the tickets before they go (probably, as electronic tickets with one-use QR Codes, in case they are separated before they arrive, to save time.) <br />
<br />
When Cueball does this he apparently sends them to White Hat's work email by mistake. When White Hat is not at work, he has an {{w|autoresponder}} activated that tells people to not disturb him as he is not at work. Usually this means that his email server sends an automatic response telling the sender of the mail that he is not at work, and not to expect an immediate reply.<br />
<br />
But in this comic, White Hat has a physical autoresponder standing behind him, drawn as a human with thicker/rougher lines as if clad in bulky clothing, wearing spiky knee and elbow guards and a spike-embossed and notably scarred crash-helmet upon its head. It casually holds a glintingly sharp sword in its hand. When Cueball inadvertently activates it, it plunges forward to 'defend' White Hat from being disturbed by work related things during his spare time. It is so aggressive that it even violently pushes White Hat out of the way, with a blow to the face so that he falls back and dislodges his hat, as it prepares to confront the perpetrator, Cueball.<br />
<br />
In the caption below, [[Randall]] states that he feel bad when he activates his friends' autoresponders. It is unclear if this is because he thinks he disturbs them with what they might think is work, because he then knows he will not get a reply or if he feels attacked (like Cueball in the comic) by their 'aggressively worded' auto-replies.<br />
<br />
In the title text Cueball shouts out (in all caps) to the autoresponder "I admire how you set boundaries and I hope your colleagues respect them! Please spare my life!" He therefore thinks it is a ''good'' idea to have time away from work where you cannot be contacted by your colleagues.<br />
<br />
It is unclear if the autoresponder is a human or a robot, but the open-faced helmet reveals the fringe and neck-length hair generally seen on female characters, Megan in particular. This would be reminiscent of the [[:Category:Android|Android series]], especially [[600: Android Boyfriend]] where one of the androids moves past its owner.<br />
<br />
==Transcript==<br />
:[Cueball and White Hat are talking to each other while Cueball is typing on his smartphone. A dark haired figure stands behind White Hat, drawn with thicker/rougher lines as if clad in bulky clothing, wearing spiky knee and elbow guards, a spike-embossed and notably scarred crash-helmet upon its head and a holding a glintingly sharp sword in its hand.]<br />
:Cueball: Ready to go?<br />
:White Hat: Yup! Can you email me the tickets before we leave?<br />
:Cueball: Sure, one sec.<br />
<br />
:[The next panel is nested inside the first, although at first it just looks like two individual panels. This could indicate the second panel is an immediate response to the first. The armored figure aggressively moves forward towards Cueball, who drops his phone in surprise. The armored figure has its sword-arm raised, the other hand pushing White Hat behind it, by pushing him in the face which causes him to stumble backwards so his hat starts to fall off.] <br />
:Cueball: Okay, I sent it to-<br />
:Armored figure: '''''It is outside work hours!'''''<br />
:Armored figure: '''''Prepare to die!'''''<br />
:Cueball: ''Augh!''<br />
<br />
:[Caption below the panel:]<br />
:I always feel bad when I trigger my friends' work autoresponders.<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring White Hat]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:221:_Random_Number&diff=223395Talk:221: Random Number2022-01-02T02:42:18Z<p>172.70.34.91: Add a little separator so the two bottom comments do not look like one comment.</p>
<hr />
<div>The syntax looks like perfectly valid java to me.[[Special:Contributions/213.64.1.189|213.64.1.189]] 22:00, 11 March 2013 (UTC)<br />
<br />
Looks like Java to me too.{{unsigned ip|139.216.242.254}}<br />
:Java code for this would be something like "public static int fin(){}" or just "public int fin(){}". I think the code would still compile though without the public/private part. {{unsigned ip|188.114.106.41}}<br />
::I know this comment is from several years ago, but I'll add this just for posterity. The "default" access modifier exists in java and is somewhere in between "private" and "protected". You can only use it by otherwise unspecifying the access modifier.[[Special:Contributions/108.162.215.187|108.162.215.187]] 16:40, 18 July 2016 (UTC)<br />
:How can Java come to mind when it is pure C syntax, which predates Java by several years and is arguably better known. A feature of most languages is that they have a "C-like syntax". See, a whole page on Wikipedia - http://en.wikipedia.org/wiki/List_of_C-based_programming_languages [[Special:Contributions/122.161.20.238|122.161.20.238]] 19:53, 22 August 2013 (UTC)<br />
::"C-like syntax" is the best explain, this covers all. Even when I disagree that it's better known than Java these days.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:04, 22 August 2013 (UTC)<br />
:::Just to be particularly pedantic, the double slash for the comment (which is generally utilised in object oriented C-style languages) should be avoided in C to retain backwards compatibility with C89, although it's a valid construct in C99. I'd offer, too, that the lack of library inclusion suggests this isn't necessarily Java, though it's been a couple years since I've had the opportunity to code in it. [[User:Thokling|Thokling]] ([[User talk:Thokling|talk]]) 15:35, 20 September 2013 (UTC)<br />
::::Not really worth putting effort in backward compatibility for stuff a simple regex can fix:<br><code>$ perl -pi.bak -e 's!//(.*)$!/\*$1\*/!' *.c</code> [[Special:Contributions/108.162.229.210|108.162.229.210]] 03:23, 5 August 2015 (UTC)<br />
<br />
As a proof of good joke, RFC 1149 was successfully implemented several times. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 08:55, 11 May 2013 (UTC)<br />
<br />
Actually, a poor “random” function like “return 4;” would be quickly determined by statistical test tools (Diehard, Dieharder, etc.) to generate very poor random number. [[User:Samiam|Samiam]] ([[User talk:Samiam|talk]]) 19:55, 28 October 2013 (UTC)<br />
:The number is random, I'm sure Randall really did this "fair dice roll". And even the name of the function is correct, it just returns a random number. A programmer would expect a random number generator, but Randall can't roll the dice all the time.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:37, 28 October 2013 (UTC)<br />
<br />
:<<sound of crickets chirping>> [[Special:Contributions/108.162.219.58|108.162.219.58]] 02:24, 6 February 2014 (UTC)<br />
<br />
;Playstation 3 jailbreak reference?<br />
<br />
Isn't this a reference to Sony Playstation 3's random number generator function that allowed to discover the private key to 3.55 firmware? {{unsigned ip|141.101.64.23}}<br />
<br />
:The comic is from February 9, 2007. The 3.55 firmware was released December 7, 2010. {{unsigned ip|173.245.50.144}}<br />
<br />
::Maybe the 3.55 firmware implemented RFC 1149.5 --[[Special:Contributions/172.70.130.109|172.70.130.109]] 20:13, 17 August 2021 (UTC)<br />
<br />
This seems to have turned up in [http://www.smbc-comics.com/comic/set-theory SMBC]. [[User:.42|.42]] ([[User talk:.42|talk]]) 20:00, 18 July 2016 (UTC)<br />
<br />
Possibly turned up in Gravity Falls. Journal 3 (book edition) states that the Infinity-Sided Die can theoretically result in any outcome, but "you'd be surprised how often you'd roll a 4." [[Special:Contributions/141.101.76.46|141.101.76.46]] 04:18, 19 October 2018 (UTC)<br />
<br />
--<br />
<br />
Unknowingly or not, this could very well be related to the gif spec. https://www.w3.org/Graphics/GIF/spec-gif89a.txt<br />
<br />
In the graphic control extension part of gif89A, a block size is allowed to be specified. And well... I'll just let the spec speak for itself:<br />
<br />
iii) Block Size - Number of bytes in the block, after the Block<br />
Size field and up to but not including the Block Terminator. This<br />
field contains the fixed value 4.</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:221:_Random_Number&diff=223394Talk:221: Random Number2022-01-02T02:40:49Z<p>172.70.34.91: Add section about how this may be in reference to gif89a spec</p>
<hr />
<div>The syntax looks like perfectly valid java to me.[[Special:Contributions/213.64.1.189|213.64.1.189]] 22:00, 11 March 2013 (UTC)<br />
<br />
Looks like Java to me too.{{unsigned ip|139.216.242.254}}<br />
:Java code for this would be something like "public static int fin(){}" or just "public int fin(){}". I think the code would still compile though without the public/private part. {{unsigned ip|188.114.106.41}}<br />
::I know this comment is from several years ago, but I'll add this just for posterity. The "default" access modifier exists in java and is somewhere in between "private" and "protected". You can only use it by otherwise unspecifying the access modifier.[[Special:Contributions/108.162.215.187|108.162.215.187]] 16:40, 18 July 2016 (UTC)<br />
:How can Java come to mind when it is pure C syntax, which predates Java by several years and is arguably better known. A feature of most languages is that they have a "C-like syntax". See, a whole page on Wikipedia - http://en.wikipedia.org/wiki/List_of_C-based_programming_languages [[Special:Contributions/122.161.20.238|122.161.20.238]] 19:53, 22 August 2013 (UTC)<br />
::"C-like syntax" is the best explain, this covers all. Even when I disagree that it's better known than Java these days.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:04, 22 August 2013 (UTC)<br />
:::Just to be particularly pedantic, the double slash for the comment (which is generally utilised in object oriented C-style languages) should be avoided in C to retain backwards compatibility with C89, although it's a valid construct in C99. I'd offer, too, that the lack of library inclusion suggests this isn't necessarily Java, though it's been a couple years since I've had the opportunity to code in it. [[User:Thokling|Thokling]] ([[User talk:Thokling|talk]]) 15:35, 20 September 2013 (UTC)<br />
::::Not really worth putting effort in backward compatibility for stuff a simple regex can fix:<br><code>$ perl -pi.bak -e 's!//(.*)$!/\*$1\*/!' *.c</code> [[Special:Contributions/108.162.229.210|108.162.229.210]] 03:23, 5 August 2015 (UTC)<br />
<br />
As a proof of good joke, RFC 1149 was successfully implemented several times. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 08:55, 11 May 2013 (UTC)<br />
<br />
Actually, a poor “random” function like “return 4;” would be quickly determined by statistical test tools (Diehard, Dieharder, etc.) to generate very poor random number. [[User:Samiam|Samiam]] ([[User talk:Samiam|talk]]) 19:55, 28 October 2013 (UTC)<br />
:The number is random, I'm sure Randall really did this "fair dice roll". And even the name of the function is correct, it just returns a random number. A programmer would expect a random number generator, but Randall can't roll the dice all the time.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:37, 28 October 2013 (UTC)<br />
<br />
:<<sound of crickets chirping>> [[Special:Contributions/108.162.219.58|108.162.219.58]] 02:24, 6 February 2014 (UTC)<br />
<br />
;Playstation 3 jailbreak reference?<br />
<br />
Isn't this a reference to Sony Playstation 3's random number generator function that allowed to discover the private key to 3.55 firmware? {{unsigned ip|141.101.64.23}}<br />
<br />
:The comic is from February 9, 2007. The 3.55 firmware was released December 7, 2010. {{unsigned ip|173.245.50.144}}<br />
<br />
::Maybe the 3.55 firmware implemented RFC 1149.5 --[[Special:Contributions/172.70.130.109|172.70.130.109]] 20:13, 17 August 2021 (UTC)<br />
<br />
This seems to have turned up in [http://www.smbc-comics.com/comic/set-theory SMBC]. [[User:.42|.42]] ([[User talk:.42|talk]]) 20:00, 18 July 2016 (UTC)<br />
<br />
Possibly turned up in Gravity Falls. Journal 3 (book edition) states that the Infinity-Sided Die can theoretically result in any outcome, but "you'd be surprised how often you'd roll a 4." [[Special:Contributions/141.101.76.46|141.101.76.46]] 04:18, 19 October 2018 (UTC)<br />
<br />
Unknowingly or not, this could very well be related to the gif spec. https://www.w3.org/Graphics/GIF/spec-gif89a.txt<br />
<br />
In the graphic control extension part of gif89A, a block size is allowed to be specified. And well... I'll just let the spec speak for itself:<br />
<br />
iii) Block Size - Number of bytes in the block, after the Block<br />
Size field and up to but not including the Block Terminator. This<br />
field contains the fixed value 4.</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2559:_December_25th_Launch&diff=223130Talk:2559: December 25th Launch2021-12-27T15:46:45Z<p>172.70.34.91: </p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Santa delivers his presents on Christmas Eve. The launch is scheduled for 9:20am French Guiana time, so Santa should be long gone during the final countdown. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 06:05, 25 December 2021 (UTC)<br />
<br />
I feel like the way it's written and also the "update" in the title text is a reference to the NORAD Santa Tracker (or maybe the Google one). I'd do it myself but it's 2AM, so can someone fact check me and possibly add it to the article assuming I'm not misremembering. Thanks, [[User:Zman350x|Zman350x]] ([[User talk:Zman350x|talk]]) 07:20, 25 December 2021 (UTC)<br />
<br />
Launches have been stopped many times at less than 8 seconds, and Randall would be familiar with this fact. The "unavoidable" bit of the explanation can safely (and preferably) be dropped. Given Randall's demonstrated frustration with Webb delays, the joke about the RSO shooting down Santa is almost certainly attributable to intolerance of another delay. [[Special:Contributions/172.70.130.213|172.70.130.213]] 07:45, 25 December 2021 (UTC)<br />
:Thanks for the heads up; edited my addition. It still feels like an italicized "oh no" is too big of a reaction to a delay that's <strike>short, unique, and measurable</strike>. Maybe forcing a launch to abort at -7 seconds causes some kind of fuel combustion(??)/consumption issue that damages some of the spacecraft and requires a much longer delay? Then this could be added to the explanation. (Obviously I'm not an expert here.) Alternatively, say it takes 7 seconds to say the words in the second and third panels, so the spacecraft has already launched. [[User:Zowayix|Zowayix]] ([[User talk:Zowayix|talk]]) 08:16, 25 December 2021 (UTC)<br />
:Edit: Found a real example of an abort delay and added to the explanation.<br />
::I mean, it kinda feels like a “straw that broke the camel’s back” type of situation here. It’s not the incident itself, it’s everything leading up to that moment and how it probably left Cueball on edge. [[Special:Contributions/108.162.215.195|108.162.215.195]] 08:30, 25 December 2021 (UTC)<br />
<br />
I think there's a barb here about NASA ruining xmas for a lot of people, by slipping the launch date to 25 December. [[User:Arithex|Arithex]] ([[User talk:Arithex|talk]]) 08:58, 25 December 2021 (UTC)<br />
<br />
As far as I know, Range Safety Officers don't have ground-to-air weapons, and are therefore incapable of shooting down Santa. when RSO's need to kill something, they use remote detonation commands. How any RSO managed to pre-place a self-destruct package aboard Santa's Sleigh remains an open question: normally they only have those placed aboard the actual rocket stages. [[Special:Contributions/172.70.130.57|172.70.130.57]] 11:15, 25 December 2021 (UTC)<br />
:That's easy: Write Santa a letter that you want a remotely controllable self-destruct package for Christmas. It will be conveniently placed on the sleigh on December 25. This must be one of the gazillion steps on the JWST pre-launch checklist. [[Special:Contributions/162.158.91.164|162.158.91.164]] 13:14, 25 December 2021 (UTC)<br />
:All will be revealed in the new {{w|How the Grinch Stole Christmas (2000 film)|Grinch}} sequel, '''How the Grinch Killed Christmas''' which details how he finds work as a Range Safety Officer. [[User:Kev|Kev]] ([[User talk:Kev|talk]]) 19:12, 25 December 2021 (UTC)<br />
<br />
While I like the current note about Santa being aware about this launch due to astronomy geeks asking for it as a present, I would note that Santa must already have extremely good collision avoidance system considering the speed his sleight is moving (at least 650 miles per second) to manage all deliveries over single night. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 03:33, 26 December 2021 (UTC)<br />
:That's assuming Santa moves with finite speed and well-defined position. Personally I'm a big fan of the time stop/time loop explanation.[[Special:Contributions/172.69.42.121|172.69.42.121]] 03:56, 26 December 2021 (UTC)<br />
<br />
Real launch aborts have occurred after T=0. For Ariane 5 launches T=0 is ignition of the main engines. Liftoff occurs when the solid boosters are ignited at T+6seconds. (This is different from NASA and other American launchers where T=0 is liftoff)[[Special:Contributions/172.70.34.91|172.70.34.91]] 15:46, 27 December 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:1870:_Emoji_Movie_Reviews&diff=222434Talk:1870: Emoji Movie Reviews2021-12-11T01:23:29Z<p>172.70.34.91: reminder</p>
<hr />
<div><!--Please sign your posts with ~~~~ and not delete this comment.--><br />
There are many ways that a movie can be bad. It could have uninteresting characters, a bad plot, stupid dialogue, poor filming etc. Very likely the Emoji movie suffers from all of these problems. I should add that Jar Jar Binks from Star Wars fame was widely hated by anyone over 8 years old but my 5-year-old loved him. Could the same thing be true for Emojis? [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 18:00, 31 July 2017 (UTC)<br />
:So, similar to the minions movie series? 20:00, 31 July 2017 (UTC)[[Special:Contributions/141.101.104.125|141.101.104.125]]<br />
::The minions and the "prequel" (I don't know the english title) are not only watched and enjoyed by children - at least in Germany - but also by young adults. [[Special:Contributions/198.41.242.5|198.41.242.5]]<br />
:::Es gibt kein Prequel zu den Minions. Die Minions sind das Prequel zu "Ich, einfach unverbesserlich", also "Despicable Me".[[Special:Contributions/162.158.88.206|162.158.88.206]] 11:08, 2 August 2017 (UTC)<br />
:::I can see how happy pills would be popular among the Germanic depressives. :P [[Special:Contributions/162.158.75.100|162.158.75.100]] 20:37, 31 July 2017 (UTC)<br />
<br />
:::Of the Star Wars prequels, the one which had the most of Jar Jar Binks was the first one, whose English name was Star Wars Episode I: The Phantom Menace. And you should note that Rtanenbaum wasn't talking about the whole movie, but specifically the character of Jar Jar Binks (the clutz alien with long floppy ears). Plus, I think most adults (or "anyone over 8 years old") hated him for how he spoke, so other language adaptations might have made him better, LOL! [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 04:03, 1 August 2017 (UTC)<br />
:::: Well, at least not in Germany XD [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:24, 1 August 2017 (UTC)<br />
<br />
Sorry, does anyone genuinely believe that the writers would not actually know about the eggplant? Out of dozens, nay hundreds of useless icons, this one would have been unconsciously selected by random chance? {{unsigned ip|162.158.2.160}}<br />
:Cueball even asks, "was that on purpose?". {{unsigned ip|162.158.146.22}}<br />
<br />
Possible title text explanation: The idea doesn't survive in the real world because (A) people typically don't express emotion by turning their head upside down, and (B) it's rare that you run into a person who is thinking (a very jaded, cynical view of humanity popular among internet users). [[Special:Contributions/172.68.54.22|172.68.54.22]] 14:43, 1 August 2017 (UTC)<br />
:I think probably the title text is more trying to emphasize the fact that emoji can be used in ambiguous/nuanced ways, as much or more than other methods of communication. [[User:Berets|Berets]] ([[User talk:Berets|talk]]) 22:33, 1 August 2017 (UTC)<br />
<br />
Considering the last comic also happens to be about reviews, is it possible Randall made a subtle comment about the Emoji Movie in 1869? [[Special:Contributions/172.68.254.108|172.68.254.108]] 17:43, 1 August 2017 (UTC)<br />
<br />
Am I the only one, wanting to watch that movie now, in order to actually verify and explain the plot summary for this site, and to be able to make a first hand guess wether the egggplant joke was a joke? [[Special:Contributions/162.158.89.115|162.158.89.115]]<br />
:You are not alone, LOL! This comic actually gave me interest in seeing the movie, I had virtually no interest before this. :) [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 03:03, 4 August 2017 (UTC)<br />
::Am I alone? After reading some news articles, wiki, and this comic I know I really do NOT need to see this movie. And furthermore I even don't need Emojis... ;-) --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 12:38, 4 August 2017 (UTC)--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 12:38, 4 August 2017 (UTC)<br />
<br />
I'm not a big emoji user, so I never knew the eggplant was a penis-representative. But this quote: "''... a sly stand-in for a penis, due to its similar shape.''" had me wondering. No penis I know looks like that (the emoji itself), unless the writer has a familiarity with saline-injection porn! [[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]]) 02:55, 6 August 2017 (UTC)<br />
<br />
"there is a very low chance of there being a 'piracy app', as an app such as this would not be allowed on any online app store." Unless it's a piracy app store. Android allows to install apps from APKs, and jailbroken iphones -- from IPA files, I think. [[User:ShareDVI|ShareDVI]] ([[User talk:ShareDVI|talk]]) 08:14, 7 August 2017 (UTC)<br />
<br />
Was ''Sausage Party'' 'trying to be controversial on purpose'? I didn't see it, but it just looked like a typical adult comedy to me. [[User:PvOberstein|PvOberstein]] ([[User talk:PvOberstein|talk]]) 18:14, 14 August 2017 (UTC)<br />
<br />
<br />
You know, there was a rant by Durex there is no condom emoji. As example, Durex offered to remove useless emoji and add condom emoji instead. Joke isz they used eggplan as example of useless emoji.<br />
<br />
I guess that's how eggplans became the meme AND the innuendo. <br />
Please sign your comment like this--[[Special:Contributions/172.70.34.91|172.70.34.91]] 01:23, 11 December 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=User:Esogalt&diff=222378User:Esogalt2021-12-10T17:21:43Z<p>172.70.34.91: </p>
<hr />
<div>I do edits sometimes.<br />
<br />
The vast majority of [citation needed] instances on this wiki are misapplied in one of two quite different but equally wrong ways.{{Actual citation needed}} Read the damn FAQ and learn to appreciate subtle humour, without trying to contort it into an overused in-joke you clearly don't understand properly.<br />
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Feel free to post on my talk page, although I'm not notified so I might take a while to respond.</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=User:Esogalt&diff=222377User:Esogalt2021-12-10T17:21:28Z<p>172.70.34.91: sorry, couldnt resist :) ~~~~BUmpf</p>
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<div>I do edits sometimes.<br />
<br />
The vast majority of [citation needed] instances on this wiki are misapplied in one of two quite different but equally wrong ways.{{Actual citation needed} Read the damn FAQ and learn to appreciate subtle humour, without trying to contort it into an overused in-joke you clearly don't understand properly.<br />
<br />
Feel free to post on my talk page, although I'm not notified so I might take a while to respond.</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=User:Lettherebedarklight&diff=222210User:Lettherebedarklight2021-12-07T19:12:41Z<p>172.70.34.91: S9me idiot made this</p>
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<div>Ignore this. Please delete it if you can</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2549:_Edge_Cake&diff=222127Talk:2549: Edge Cake2021-12-06T21:15:53Z<p>172.70.34.91: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
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The cake being all edges is a reference to everything about her birth being an edge case.<br />
[[Special:Contributions/172.70.110.227|172.70.110.227]] 03:41, 2 December 2021 (UTC)<br />
: It seems likely that the title of the comic is a related pun: her birthday is an edge case, and so she has an edge cake.[[Special:Contributions/162.158.106.221|162.158.106.221]] 04:22, 2 December 2021 (UTC)<br />
So is Hairbun officially named Emily now, sort of like how all instances of Megan are Megan even though she's only called that once? I know all the names here are just placeholders of convenience, but even then I've never know what the rules for naming are. [[User:Captain Video|Captain Video]] ([[User talk:Captain Video|talk]]) 06:11, 2 December 2021 (UTC)<br />
: Well, Megan is referred to multiple times in the xkcds as "Megan", while the one time Hairbun was called Emily, it referred to the real{{citation needed}} Emily Dickinson. So, probably not. <span style="font-family:serif">[[User:Bubblegum|<span style="color:#00BFFF">bubblegum</span>]]-[[User_talk:Bubblegum|<span style="color:#BF7FFF">talk</span>]]|[[Special:Contributions/Bubblegum|<span style="color:#FF7FFF">contribs</span>]]</span> <span style="font-family:serif">02:44, 3 December 2021 (UTC)</span><br />
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Edge pieces on cake are often sought after because they hold more frosting, for cakes which are frosted while out of the pan. [[Special:Contributions/172.70.134.23|172.70.134.23]] 06:37, 2 December 2021 (UTC)<br />
: I have an impression that Cueball is delighted by having only edge pieces, however some cakes edge pieces may be either sought for or avoided, depending on one's tastes. E.g. tarts have more crispy base cake content and less filling at the edges. One person may go for the filling, another for the crispy base. -- [[Special:Contributions/162.158.102.11|162.158.102.11]] 09:50, 2 December 2021 (UTC)<br />
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So it seems the events in the comic happened on Apr 1., as the "last month" birthday could be either Feb 28. or 29. -- [[Special:Contributions/162.158.102.11|162.158.102.11]] 09:50, 2 December 2021 (UTC)<br />
:Not necessarily. Remember, Emily can have her birthday ''whenever she wants'', so the date this comic is set as is entirely arbitrary. [[Special:Contributions/172.70.178.51|172.70.178.51]] 12:26, 2 December 2021 (UTC)<br />
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Are there any particular existing arctic international flights that could have been the one Emily was born on? -- [[Special:Contributions/256.256.256.256|256.256.256.256]] 15:51, 2 December 2021 (UTC)<br />
:There are a few possibities (at least pre-COVID, and obviously we'd be looking historically in this case anyway) as [https://interestingengineering.com/polar-routes-flights-that-go-over-earths-poles might be shown here]. There's two possible (but neither definite) International Datelines on the comic diagram, in case they help orient which from/to directions might have been diverted further in or out of their own kinks in the flightpath to coincide with 90°N. [[Special:Contributions/172.70.162.77|172.70.162.77]] 16:21, 2 December 2021 (UTC)<br />
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Expanded copies of this comic have been appearing on other comics, so large that it fills the whole screen for me. Is anyone else having this problem? [[User:Sarah the Pie(yes, the food)|Sarah the Pie(yes, the food)]] ([[User talk:Sarah the Pie(yes, the food)|talk]]) 22:24, 2 December 2021 (UTC)<br />
:Someone (check the [[Special:RecentChanges|Recent Changes]] page, if you want) has been vandalising a lot of things. Currently I see a picture of an amphibious avian creature on this article's top (if I still need to revert it myself, I will do, but I've seen others have already been reverting other recent vandalism, so I may not need to by the time I've checked again). This very clever individual is obiviously mentally superior to us all(!) the way they can edit wiki pages seemingly at will... Impressive, eh? At some point I'm sure we'll get back to normlal, however boring that may be. [[Special:Contributions/172.70.90.67|172.70.90.67]] 23:33, 2 December 2021 (UTC)<br />
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Not to be too pedantic but isn't rotation a FREQUENCY, not a SPEED? [[User:Skulker|Skulker]] ([[User talk:Skulker|talk]]) 03:19, 3 December 2021 (UTC)<br />
:Depends on the context (and scale). The convention is usually speed for rotation (surface(distance/time) when it's relevant, angular(revolutions/time) otherwise) to avoid conflicts with wave frequency (which is independent of speed). Also they can be freely converted, though converting to and from surface speed requires an additional radius term. The exception is, if comparing periodicity, sometimes frequency is used when it has special relevance (Ex: resonance) -- [[Special:Contributions/172.69.68.200|172.69.68.200]] 02:59, 4 December 2021 (UTC)<br />
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Tempted to add a link in the Trivia section to the [https://en.wikipedia.org/wiki/SS_Warrimoo Wikipedia] or [https://www.snopes.com/fact-check/ss-warrimoo/ Snopes] pages on the SS Warrimoo, a ship that (reportedly) was on the intersection of the Equator and the International Date Line at the stroke of midnight on January 1, 1900, with a number of interesting implications that follow. There's no way to prove that it actually happened, but it's fun to imagine and is somewhat similar to the premise of the comic. --mezimm [[Special:Contributions/108.162.221.15|108.162.221.15]] 14:33, 3 December 2021 (UTC)<br />
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Many airplanes actually have limitations written into their operating manuals that prohibit flying north of 89 deg. N or south of 89 deg. S, mostly just so that the navigation software doesn't have to deal with the singularity. [[Special:Contributions/172.69.71.187|172.69.71.187]] 23:48, 3 December 2021 (UTC)<br />
:bloody lazy engineers! [[Special:Contributions/108.162.219.107|108.162.219.107]] 12:19, 5 December 2021 (UTC) <br />
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Is it not possible that Emily's birth happened to occur at the same moment that the contract specified transfer of ownership? Additionally, is it not possible that the airplane took off from within UTC+13:00 or UTC+14:00 and that the moment of Emily's birth happened to occur in the brief one-or-two hour period in which it was March 1st at that airport, but February 28th in UTC-12:00? UTC-11:00 is inhabited, so it would be possible that ownership of an airplane that took off from within UTC+14:00 was transferred to a company based out of UTC-11:00 during the one-hour period that it was February 28th in UTC-11:00 and March 1st in UTC+14:00 and that, at that exact moment, it was passing over the North Pole. [[User:DL Draco Rex|DL Draco Rex]] ([[User talk:DL Draco Rex|talk]])<br />
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Am I alone in thinking that babies don't get born instantaneously? I've never given birth myself but i'd always got the impression that it's a process and any attempt to pick a precise 'instant' is going to be somewhat arbitrary. This means that the plane will very probably have travelled through a variety of time zones any of which could be the 'real' time of birth. [[Special:Contributions/172.70.85.155|172.70.85.155]] 05:29, 4 December 2021 (UTC)<br />
:Time of birth is an arbitrary decision made by the midwives filling out forms in a hospital. The more unlikely point about that is that she'd be able to correlate the precise position of the plane at the exact time listed. [[Special:Contributions/108.162.219.187|108.162.219.187]] 12:37, 5 December 2021 (UTC)<br />
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Dickenson looks like a typo. Dickinson? [[Special:Contributions/172.70.162.77|172.70.162.77]] 08:44, 4 December 2021 (UTC)<br />
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Isn't an "all edge pieces cake" just a plate of cupcakes lol? [[User:Zman350x|Zman350x]] ([[User talk:Zman350x|talk]]) 06:46, 5 December 2021 (UTC)<br />
:Only if you frosted all sides of it.[[Special:Contributions/172.70.114.3|172.70.114.3]] 12:25, 5 December 2021 (UTC)<br />
:Alton Brown made a similar argument, but after experimenting, I strongly disagree. As with brownies, the cooking pattern is slightly different between having more edges and having a cupcake shape. In an edge piece, the edges and the corners are crisp while the center is gooey. Meanwhile, if cooked in a cupcake tin, while there might be more crispness, there is significantly less gooeyness. [[User:Cwallenpoole|Cwallenpoole]] ([[User talk:Cwallenpoole|talk]]) 14:23, 6 December 2021 (UTC)<br />
:If you cut the sheet into quarters or if the whole was round and cut with radial slices there won't be any center piece(s). And there are more, unusual cuts that could result in all edge pieces...[[Special:Contributions/172.70.34.165|172.70.34.165]] 14:40, 6 December 2021 (UTC)<br />
:My take was that a normal cake was baked, frosted and cut (with both edge and center pieces), and only the edge pieces were delivered to Emily.</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2550:_Webb&diff=2220982550: Webb2021-12-06T01:44:31Z<p>172.70.34.91: </p>
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<div>{{comic<br />
| number = 2550<br />
| date = December 3, 2021<br />
| title = Webb<br />
| image = webb.png<br />
| titletext = Each one contains a chocolate shaped like a famous spacecraft and, for the later numbers, a pamphlet on managing anxiety.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by the JOHN NETT LAND MICROSCOPE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
This comic depicts an {{w|advent calendar}} geared toward astronomers anticipating the launch of the {{w|James Webb Space Telescope}}.<br />
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The James Webb Space Telescope is (currently, but after [[2014: JWST Delays|many prior delays]]) scheduled to be launched on the 22nd of December. Christmas will indeed come early for astronomers should the launch be successful.<br />
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A normal advent calendar marks the days until Christmas by allowing 'doors' to be opened, or other means of revealing some treat/picture. This is often from the 1st of the month until the 'big reveal' on the 24th or 25th, though other schemes may exist for cultural reasons. This particular calendar features 18 hexagonal features, intended to be sequentially accessed over several days, deliberately similar to the 18 gold-beryllium mirror segments designed to fold out to form the JWST's primary mirror. The first door is on the 5th, two days after this comic's publication date, while the last is the 22nd, marking 'The Big Day'.<br />
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Cueball's question could be interpreted two ways: Cueball doesn't know about JWST, so he is asking why this advent calendar ends before Christmas (and possibly fearing this calendar is similar to the one in [[1245: 10-Day Forecast]]); or Cueball does know about JWST and its history of delays, so he is asking why the calendar ends on 22 when there is no certainty in that launch date (and also implying that he expects it to be delayed). <br />
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December 22 is also the day after the northern hemisphere winter solstice. The end of the world was famously predicted for the winter solstice in [[998: 2012|2012]].<br />
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The title text references the fact that chocolates in advent calendars are often molded into different shapes, and the fact that the later numbers have a "pamphlet on managing anxiety" is probably supposed to quell the impeding fear that the launch would be delayed (or go wrong). The telescope's launch was initially planned for 2007, but due to various redesigns, financial issues, accidents, flaws, and the {{w|COVID-19 pandemic}}, the launch date was pushed back to 2011, then 2013, 2018, 2020, May 2021, October 2021, and finally to the current launch date in December 2021. It may also allude to post-launch concerns; even if the launch goes well, there will still be nervousness about reaching its intended observation point, unfolding/deploying successfully, and passing its final calibrations without problems. There are effectively no means to rescue/repair this expensive piece of equipment should anything be discovered to be amiss, unlike the {{w|Hubble Space Telescope}}, which was visited five times by the Space Shuttles to remedy and enhance various features. (There exist issues with even the HST that cannot currently be considered repairable, without the Shuttles or any proven replacement, and the JWST is to be located far beyond Hubble's operational orbit in a place expensive to get to.)<br />
<br />
The JWST has been referenced previously in [[1730: Starshade]], [[2014: JWST Delays]], and [[2447: Hammer Incident]], as well as indirectly in [[975: Occulting Telescope]] and [[1461: Payloads]].<br />
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==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
:[Cueball and Ponytail are looking at an advent calendar. The advent calendar is in a hexagon shape, with 18 smaller hexagons with numbers ranging from 5-22 written on them.]<br />
:Cueball: The hexagons are nice.<br />
:Cueball: But why does it end at 22?<br />
:[Caption below the panel:]<br />
:Astronomer Advent Calendar<br />
<br />
{{comic discussion}}<br />
[[Category:Calendar]]<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Ponytail]]<br />
[[Category:Telescopes]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2546:_Fiction_vs_Nonfiction&diff=221352Talk:2546: Fiction vs Nonfiction2021-11-25T16:47:04Z<p>172.70.34.91: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Doris Kearns Goodwin also mentioned in https://xkcd.com/2160/ [[Special:Contributions/172.70.174.35|172.70.174.35]] 05:51, 25 November 2021 (UTC)<br />
<br />
Why "Boba Fett's Gadgets and How He Got Them" is not described? It is clearly a mix of sort-of-facts - description of Fett's gadgets and how artists designed them, and fiction stories of how he got them.{{unsigned}}<br />
: well, it could also be a list of what the gadgets are in-universe and the stories of how he got them, which is non-fiction in the star wars universe but fiction in real life. [[Special:Contributions/172.70.34.91|172.70.34.91]] 16:47, 25 November 2021 (UTC)Bumpf<br />
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(Edit comment) "Bobba Fett's armor is definitely Beskar, as shown in the Mandalorian season 2. However, there are conflicting official star wars publications that mention his armor being durasteel. The commonly accepted solution is that it is an alloy of both."... Or a composite laminate/overlay. Like Stormtrooper armor has a layer of Explodium on the inside, hence how Rebel gunshots are so incapacitating to them. [[Special:Contributions/172.70.85.155|172.70.85.155]] 09:25, 25 November 2021 (UTC)<br />
*Nope, they're made of "implodium" otherwise someone else might get hurt. [[User:SDSpivey|SDSpivey]] ([[User talk:SDSpivey|talk]]) 16:02, 25 November 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2545:_Bayes%27_Theorem&diff=2211732545: Bayes' Theorem2021-11-22T21:23:15Z<p>172.70.34.91: </p>
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<div>{{comic<br />
| number = 2545<br />
| date = November 22, 2021<br />
| title = Bayes' Theorem<br />
| image = bayes_theorem.png<br />
| titletext = P((B<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a FALSE POSITIVE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
Presenter: Given These Prevealences, Is it likely that the test result is a false positive?<br />
Offscreen: Well, This chapter is on Baye's Theorem, so yes.<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Miss Lenhart]]<br />
[[Category:Statistics]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=1492:_Dress_Color&diff=2204561492: Dress Color2021-11-07T15:22:39Z<p>172.70.34.91: /* Explanation */</p>
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<div>{{comic<br />
| number = 1492<br />
| date = February 27, 2015<br />
| title = Dress Color<br />
| image = dress_color.png<br />
| titletext = This white-balance illusion hit so hard because it felt like someone had been playing through the Monty Hall scenario and opened their chosen door, only to find there was unexpectedly disagreement over whether the thing they'd revealed was a goat or a car.<br />
}}<br />
<br />
==Explanation==<br />
This comic shows two drawings of [[Megan]] wearing the same dress, but with different background (and body) colors. The two drawings are split with a narrow vertical portion of an image from the web.<br />
<br />
The comic strip refers to a {{w|the dress|dress}} whose image went viral on [http://swiked.tumblr.com/post/112174461490/officialunitedstates-unclefather Tumblr] only hours before the strip was posted and soon showed up also on [http://www.reddit.com/r/explainlikeimfive/comments/2xaprc/eli5why_does_this_dress_appear_whitegold_to_some/ Reddit], [https://twitter.com/hashtag/thedress?src=hash Twitter], [http://www.wired.com/2015/02/science-one-agrees-color-dress/ Wired] and on [http://www.nytimes.com/2015/02/28/business/a-simple-question-about-a-dress-and-the-world-weighs-in.html The New York Times].<br />
<br />
Due to the dress's particular color scheme and the exposure of the photo, it forms an {{w|optical illusion}} causing viewers to disagree on what color the dress actually seems to be. The xkcd strip sandwiches a cropped segment of the photographed dress between two drawings which use the colors from the image against different backgrounds, leading the eye to interpret the white balance differently, demonstrating how the dress can appear different colors depending on context and the viewer's previous experiences.<br />
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Both dresses have exactly the same colors actually:<br />
*RGB 113, 94, 58 (orange) <div style="display:inline-block; height:1em; width:1em; background-color: #715E3A"></div><br />
*RGB 135, 154, 189 (blue) <div style="display:inline-block; height:1em; width:1em; background-color: #879ABD"></div><br />
<br />
Below is an illustration demonstrating that the "colors" of the [https://nvuvu.com/collections/sparkly-dresses/ dresses] are the same by connecting them with two lines with the above-mentioned colors (all the way!) and another which has one side flipped and merged into the other:<br />
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[[File:dress.png]] [[File:dress2.png]]<br />
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Similar types of illusions can be seen at Wikipedia's {{w|Optical illusion#Color_and_brightness_constancies|optical illusion page}} and for instance here at [http://www.echalk.co.uk/amusements/OpticalIllusions/colourPerception/colourPerception.html echalk] (the latter page requires Flash®player).<br />
<br />
This image has sparked surprisingly heated debate in many internet communities. A select few individuals may have prior experience with optical illusions of this ilk, but because this particular image went viral - it got heavy exposure over such a short amount of time - it reached millions of people who aren't so familiar with these sorts of mind tricks. To the uninitiated, the color of the dress seems immediately obvious; when others cannot see it their way, it can be a surreal (even uncomfortable) experience.<br />
<br />
As an aside, the retailer Roman Originals would later [http://i0.kym-cdn.com/photos/images/newsfeed/000/921/267/de3.png confirm the dress was blue with black lace], and that a white dress with gold lace was not offered among the clothing line.<br />
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The title text refers to the game show {{w|Let's Make a Deal}}, hosted by Monty Hall, which was famous for having contestants pick among several doors which either had a real prize (for example, a car) or a joke prize (for example, a goat). [[Randall]] states that people find the dress color issue just as baffling as if upon opening the chosen door no one can agree if the item behind the door is a car or a goat. This is a reference to what has become known as the "{{w|Monty Hall problem}}:" if there are two goats and a prize behind three doors, the contestant has chosen a door, and one of the unchosen doors is opened to reveal a goat, should the contestant change his/her choice? Statistically, the answer is yes, but many people find this counterintuitive; discussion of this problem in ''Parade'' magazine touched off public outrage similar to the viral dress image.<br />
<br />
Randall is presumably pointing out how ridiculous it is for people who don't understand the underlying science to become so adamant in defending their beliefs. A spoof of the "Monty Hall problem" previously appeared in [[1282: Monty Hall]], where [[Beret Guy]] decides to take the goat.<br />
<br />
==Transcript==<br />
:[Two images of Megan in a dress on each side of an image of a close up of a real dress with the same colors. On the left, she is colored blue on a dark blue background, while on the right, she is brown against a white background. Her dress is the same color in each panel - the same as the real one in between.]<br />
<br />
{{comic discussion}}<br />
[[Category:Comics with color]]<br />
[[Category:Comics featuring Megan]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2532:_Censored_Vaccine_Card&diff=2196702532: Censored Vaccine Card2021-10-23T00:02:24Z<p>172.70.34.91: </p>
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<div>{{comic<br />
| number = 2532<br />
| date = October 22, 2021<br />
| title = Censored Vaccine Card<br />
| image = censored_vaccine_card.png<br />
| titletext = CVS's pharmacies are fine, but I much prefer their [censored]s.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by COVID-13's 5TH DOSE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
This comic is loosely related to a series of comics related to the 2020 pandemic of the coronavirus SARS-CoV-2, which causes COVID-19. <br />
<br />
The comic hinges on sharing photos on social media of vaccination cards as proof that the user has been vaccinated (in this case, gotten a booster shot). Such cards contain personal identification that should probably not be made public. The irony is that the user has censored some impersonal lines, such as the instructions that are identical on all vaccination cards, and many easy-to-guess lines, while not censoring any of said personal information.<br />
The fourth line, labelled "other" is probably completely blank (as the third dose was on the current date), but is completely blacked out.<br />
<br />
The caption indicates that his intention is to "seem more mysterious". This is best exemplified by blanking most of the word "clinician" to leave "CIA".<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
:[Profile picture with three unreadable lines on its left:<br />
Check it out, I just got my booster! <br />
<br />
:[Picture of the U.S. COVID-19 Vaccination Record Card attached on a media post. The card includes pre-printed information in black and handwritten information in blue, the latter indicated here by italics. Some of the text has been blacked out, indicated here by "[Censored]".]<br />
<br />
:COVID-:[Censored] Vaccination record card<br />
:[At the upper right of the card appears the logo of the U.S. Department of Health and Human Services, a stylized eagle surrounded by the words "Department of Health & Human Services USA", although those words are not legible in this drawing. Next to that appears the logo of the Centers for Disease Control and Prevention, a shaded box with the letters "CDC" and the words "Centers for Disease Control and [Censored]" below it.]<br />
----<br />
<br />
<br />
:Please keep this record card, which includes [Censored]<br />
:about [Censored]<br />
:Por favor, guarde esta tarjeta de registro, que incluve [Censored]<br />
:[Censored] sobre [Censored]<br />
<br />
:''Munroe'' ''Randall''<br />
----<br />
:Last Name First Name<br />
<br />
:''10-17-[Censored]84'' ''41592653''<br />
----<br />
:Date of birth Patient number<br />
<br />
{{comic discussion}}</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2526:_TSP_vs_TBSP&diff=219037Talk:2526: TSP vs TBSP2021-10-08T18:26:12Z<p>172.70.34.91: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
The title text refers to lyrics in the Alanis Morissette song Ironic -MonteCarloe [[Special:Contributions/172.70.126.211|172.70.126.211]] 16:59, 8 October 2021 (UTC)<br />
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I wonder why Randall used 1024^4 instead of 2^40. -MonteCarlo [[Special:Contributions/162.158.74.150|162.158.74.150]] 17:10, 8 October 2021 (UTC)<br />
:To highlight the similarity between 1000 and 1024, I suppose.--[[User:Pere prlpz|Pere prlpz]] ([[User talk:Pere prlpz|talk]]) 18:03, 8 October 2021 (UTC)<br />
:And a byte is 1024^0 bytes, kilobyte=1024^1, megabyte=1024^3, etc. Talking entirely in terms of 2^10N loses the sheer simplicity and easy approximation.<br />
:(Though not as much as 'short' -illions. 5.45 trillion? That's 5, then the decimal padded/shortened to exactly three figures (450), ''then'' three sets of three zeros. Stupid system.) [[Special:Contributions/172.69.54.136|172.69.54.136]] 18:20, 8 October 2021 (UTC)<br />
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A table with common or interesting volumes measured in teraspoons would be a good addition.--[[User:Pere prlpz|Pere prlpz]] ([[User talk:Pere prlpz|talk]]) 18:03, 8 October 2021 (UTC)<br />
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he did kilonife kiloknife because the k in knife stands for kilo [[Special:Contributions/172.70.34.91|172.70.34.91]] 18:26, 8 October 2021 (UTC)Bumpf</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2521:_Toothpaste&diff=218628Talk:2521: Toothpaste2021-09-28T22:12:49Z<p>172.70.34.91: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
The editing done so far looks fairly good. Hopefully not too many reversions, or it might be like moving the deckchairs back to their original locations on the Titanic! [[Special:Contributions/172.70.35.70|172.70.35.70]] 05:46, 28 September 2021 (UTC)<br />
<br />
Was Megan going to say: "It's just like- putting toothpaste back in the tube"? If so this should go into the description (and if not then what was she going to say?) --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:40, 28 September 2021 (UTC)<br />
<br />
Putting the mouth over the tube? It is not the tooth paste in your mouth that needs to get back. It is that on the tooth brush... I think it is possible (although not sanitary) to get tooth paste still in a blob on the tooth brush into the tube if it is a soft plastic tube. Because then when you press it together, the air comes out, and then when you release it will suck air back in (I have seen how the paste coming out gets sucked back in if it is not put on the brush). But if you then put the end of the tube onto the blob of toothpaste on the brush, it would suck the paste right back in. So I think it is true that you can get the paste back in the tube. But not by blowing, and of course there are many kinds of toothpaste containers, and not all of them could suck it back in. You should not put it back but you could! So it is a bad saying, and Megan is correct in pointing that out. What she suggest is disgusting, though, for sure. If that is the worst she ever said, though, she has been too kind to Cueball :-D In some ways it is not a very great comic, but I guess the fun part is when she assumes that she can take something bad said back because Cueball states you can do with things said like tooth paste back in a tube, and since you can put toothpaste back in the tube, she must be able to take her words back. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:50, 28 September 2021 (UTC)<br />
:The tubes I have experience with may be able to suck a bit of paste back, but not much of it - they have little to no elasticity or how it's called, you permanently deform them when squeezing paste out. You would need to apply pressure, which, well, you either need some machine for or blow into them. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 16:09, 28 September 2021 (UTC)<br />
<br />
I disagree that blowing paste into tube is disgusting. Now, reusing such paste, sure, although it's unlikely to be that much unhygienic as I don't think the bacteria can survive in tooth paste for long. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 16:09, 28 September 2021 (UTC)<br />
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Putting toothpaste back in the tube is easy with a syringe or an icing gun. But I want to know what happened at the 10th dentist's office? [[User:Cwallenpoole|Cwallenpoole]] ([[User talk:Cwallenpoole|talk]]) 16:58, 28 September 2021 (UTC)<br />
<br />
I always heard it as "you can't put the genie back in the bottle". [[Special:Contributions/172.70.34.165|172.70.34.165]] 18:02, 28 September 2021 (UTC)<br />
<br />
i have literally never heard this expression [[Special:Contributions/172.70.34.91|172.70.34.91]] 22:12, 28 September 2021 (UTC)Bumpf</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2520:_Symbols&diff=218509Talk:2520: Symbols2021-09-25T20:08:30Z<p>172.70.34.91: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
<br />
Great work by whomever did this, but is it possible R_e is something else? I agree that the numerical aspect makes it seem like a fluid mechanics problem, but I've never seen the Reynolds number with a subscripted e... only a regular size e, such that it is Re, not R_e. [[Special:Contributions/108.162.237.93|108.162.237.93]] 20:36, 24 September 2021 (UTC)<br />
: R sub e (not Re) is Effective Reproduction Number. This is related to infection rates. I'm pretty sure it's R sub e, not Re given that infection rates are very much on his mind right now.<br />
:: It would be out of place relative to all the other entries, though, which are all physics related. IMO it's more likely this was an error.<br />
: Earth's radius is abbreviated "R sub e" [[Special:Contributions/162.158.107.4|162.158.107.4]] 21:30, 24 September 2021 (UTC)<br />
: Could be the remainder of a series (i.e. the error when using the first terms of the series as an approximation). Determining upper bounds on this error is usually very tedious.<br />
: R sub e is tire effective rolling radius (or effective radius)--a radius based on the distance traveled by one rotation of a pneumatic tire. Re is similar to the unloaded radius (for radial tires) and normally larger than the loaded radius (distance from axle to ground).<br />
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T to the fourth power looks like blackbody radiation, any ideas what specifically that formula represents? [[Special:Contributions/162.158.203.22|162.158.203.22]] 20:40, 24 September 2021 (UTC)<br />
:There's an equation for what reflects off a spherical object that is a quartic equation (although I'd expect concave reflectors, not convex ones, to risk skin-burn. Or, more likely something to do with UV (non-)absorbtion or generation, but I imagine someone knows ''exactly'' what it is, without someone like me just guessing wildly. ;) [[Special:Contributions/141.101.99.82|141.101.99.82]] 21:05, 24 September 2021 (UTC)<br />
This wiki does not seem to have a consistent formatting structure for lists<br />
<br />
The ''N<sub>A</sub>'' could also soon become NAN (not a number) thus being only a step away from the dangerous arthmeric error. --[[Special:Contributions/162.158.88.43|162.158.88.43]] 21:38, 24 September 2021 (UTC)<br />
<br />
'''Bold Title'''<br />
:Content starting with a tab<br />
<br />
<br />
*'''Bold title''' content continues on same line<br />
<br />
<br />
*Regular title<br />
Content on a new line, but not starting with a tab<br />
<br />
As well as tables and mixes of these formats. Maybe someone should pick one and apply it to all the explanations. I just noticed it because of the inconsistencies as people are quickly throwing something together for this new comic. [[Special:Contributions/162.158.107.4|162.158.107.4]] 21:02, 24 September 2021 (UTC)<br />
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I read the penultimate line as "Mg" and was trying to imagine a meaning for "megagrams per kilogram". Sloppy Greek letter there, Randall. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 03:17, 25 September 2021 (UTC)<br />
<br />
Why are partial derivatives considered graduate-level? They're typically covered in first level undergraduate science courses, along with gradients and such. [[User:FPSCanarussia|FPSCanarussia]] ([[User talk:FPSCanarussia|talk]]) 03:34, 25 September 2021 (UTC)<br />
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The reference to "micrometer" links to the Wikipedia page for the measuring device, but it should link to the page for the unit of length: https://en.wikipedia.org/wiki/Micrometre [[User:Professor Frink|Professor Frink]] ([[User talk:Professor Frink|talk]]) 15:58, 25 September 2021 (UTC)<br />
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Adding to “Micrometer/Micrometre” above: this “any” is not really correct:<br />
:Of course, micrometers are used as a measurement of distance in other contexts, but any distance-measuring device capable of accurately measuring micrometer distances would also be expensive.<br />
The “Micrometers” as seen in the Wikipedia article can measure distances of some micrometers accurately, but are not really expensive. Probably even cheaper than any equipment which can ''not'' measure distances. --[[Special:Contributions/162.158.88.239|162.158.88.239]] 18:19, 25 September 2021 (UTC)<br />
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In certain circles (or, perhaps, between them as they roll), the typical Reynolds number is {{w|Reynolds Technology|just three digits}}... ;) [[Special:Contributions/162.158.159.95|162.158.159.95]] 20:04, 25 September 2021 (UTC)<br />
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"When radiative transfer is large enough to be the most important form of heat interchange, it is normally also large enough to sear the skin with thermal or ultraviolet burns." Radiative transfer is the dominant heat transfer from a (idle) human body in a 20C room. There is no risk of seared skin in this situation. As an aside if people understood the role of radiative heat transfer we'd have more comfortable and cheaper HVAC systems (and more underfloor heating).[[Special:Contributions/172.70.34.91|172.70.34.91]] 20:08, 25 September 2021 (UTC)<br />
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I cannot recall ever using Avogadro's constant in a stochiometric calculation. You do everything in mole or gram mole. N<sub>A</sub> implicitly cancels and never even appears.[[Special:Contributions/172.70.34.91|172.70.34.91]] 20:08, 25 September 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2516:_Hubble_Tension&diff=2181462516: Hubble Tension2021-09-17T14:23:17Z<p>172.70.34.91: /* Explanation */ Corrected wording of measurement via radar gun to "speeds" not "distances.</p>
<hr />
<div>{{comic<br />
| number = 2516<br />
| date = September 15, 2021<br />
| title = Hubble Tension<br />
| image = hubble_tension.png<br />
| titletext = Oh, wait, I might've had it set to kph instead of mph. But that would make the discrepancy even wider!<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by Dave - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
[[Ponytail]] is telling [[Cueball]] about the {{w|expansion of the universe}} telling him that there are three main estimates of the rate of expansion, and that they all disagree. She then tells him of the two well known (and very complicated) methods, and finally the joke is that the third method is performed by a guy named Dave (who replies from off-panel), and he claims to measure the speeds with a radar gun, as if the galaxies were speeding here on Earth.<br />
<br />
The fact that most {{w|galaxies}} are receding from us, and that the distance to the galaxy is directly proportional to the speed (as measured by {{w|red-shift}}) was discovered in the 1920s by {{w|Edwin Hubble}} and others. This constant of proportionality is known as the {{w|Hubble Constant}}.<br />
<br />
One way of measuring the Hubble Constant is to measure the distance to (relatively) nearby galaxies. Once distance is obtained, speed can be easily obtained by measuring the red-shift and thus the Hubble Constant calculated. Measuring the distance turns out to be fiendishly difficult because a distant bright star looks the same as a dim star that is closer, and localized movements can influence the speed of recession &mdash; though less significantly, for multiple reasons, the further away are the objects that you study.<br />
<br />
In practice, astronomers have a number of ways of measuring distance that work at different scales, and they can be built upon to measure distance to far away galaxies. This is known as the {{w|Cosmic distance ladder}}. <br />
<br />
The first rung is {{w|parallax}}. As the Earth orbits around the Sun, nearby stars appear to move slightly relative to distant stars; a star that moves by one second of arc is said to have a distance of 1 {{w|Parsec}} &mdash; about 3¼ light years or 30 trillion (3x10<sup>13</sup>) kilometers. <br />
<br />
The next rung is {{w|Cepheid variables}}, which periodically brighten and dim. The frequency of variation is related to the absolute brightness of the star, and thus by comparing the absolute to the relative brightness (subject to the {{w|Inverse-square law}} where not otherwise obscured) the distance can be measured. <br />
<br />
The final rung is {{w|Type Ia supernova}}, which occur when an accreting {{w|white dwarf}} exceeds 1.4 solar masses. Because the initial mass is always identical, the absolute brightness of the explosion is as well, so the distance can be similarly calculated.<br />
<br />
Putting these together, the best measurement of the Hubble Constant is 73 km/s/Mparsec.<br />
<br />
This is in conflict with the other main way of measuring the Hubble Constant, analyzing makeup of the {{w|Cosmic Microwave Background}} (CMB) radiation, which yields a value of 68 km/s/Mparsec. The difference is statistically significant, and well outside the error bounds of each measurement.<br />
<br />
Since the CMB technique relies on our understanding and assumptions about the early universe, as well as on the cosmological effects of General Relativity on large scales, if this discrepancy proved real it could be the gateway to new discoveries in cosmology and gravity, as well as possibly shed light on the origin of the universe and a '{{w|Theory Of Everything}}'. Cosmologists got quite excited about this. It might also be that there was a previously unaccounted-for error in any of the rungs of the cosmological distance ladder, and that once that is fixed, the two results will be consistent.<br />
<br />
The third method introduced in this comic is a guy named Dave who is trying to use a {{w|radar speed gun}} (as used by the police for detecting speeding cars) to try to measure the movement of astronomical bodies. A radar system works by sending electromagnetic radiation from the gun and then measuring the returned radiation to determine how far away or how fast a moderately distant object is moving. Because of the transmission and return times required (and the inverse-square law), a radar device will only be able to get information about the very closest objects, such as the Moon (a type of {{w|Earth–Moon–Earth communication|Moon bounce}}) and other objects orbiting the Earth (or ''perhaps'' the Sun), where the influence of being in orbit utterly dominates over any possible Hubble-shift. And that still needs powerful radar systems like the former {{w|Arecibo Telescope}} to be able to get any useful information that far away, a hand-held radar gun would not be able to 'lock on' across even those distances.<br />
<br />
Going by back-calculating grossly 'idealized' universe models, as suggested by the other two estimates, a receding velocity of 85 miles per hour ('mph'; about 137 kilometers per hour, 'kph' or 'km/h') should be seen at a distance of roughly 1700-1850 light-years, on the order of the thickness of our galactic disc. Much too far to use a radar gun on, also much too close to exclude any significant galactic stellar motions. Much the same is true if the figure is actually 85 kph (1050-1130 ly), as suggested it might be in the title text.<br />
<br />
Aside from being practically incorrect, that value of 85 kph relates to around 53 mph, which might be the normally observed traffic speed on certain roads (especially if someone is conspicuously using a radar gun!) if by 'all directions' you effectively mean 'both directions' of traffic flow that Dave could possibly be measuring. Dave may have been referring to the kind of {{w|Ford Galaxy|Galaxy}} that he ''can'' more easily find out the velocity of.<br />
<br />
The comic is likely making fun of the common internet phenomenon of amateur (wannabe?) scientists seeking to discredit established scientific facts by reporting the results of experiments made using everyday tools. Dave has probably heard of the fact that there is no agreement in the scientific measurements of the Hubble constant and decided to try to settle the controversy using the tools at his disposal, without remotely realizing that the margin of error required in the measurements is well outside the range of what can be used with conventional objects.<br />
<br />
Dave might also lack an understanding of units of measure and dimensions. Ponytail describes the measurements of the rate of universal expansion, a speed that varies with distance, in km/s/Mparsec, having dimension 1/T or 1/time. Dave made his measurements in miles/hour or km/h, which have dimension L/T or length/time. These are not comparable with the official units. Dave does not appear to be aware of this (and Ponytail does not draw Cueball or Dave's attention to it).<br />
<br />
==Transcript==<br />
:[Cueball and Ponytail are walking to the right. Ponytail has her palm raised.]<br />
:Ponytail: There are three main estimates of the universe's expansion rate and they all disagree.<br />
<br />
:[They keeping walking to the right.]<br />
:Ponytail: Measurements of star distances suggest the universe is expanding at 73 km/s/megaparsec.<br />
<br />
:[They are still walking to the right.]<br />
:Ponytail: Measurements of the cosmic microwave background suggest it's expanding at 68 km/s/megaparsec.<br />
<br />
:[They continue walking to the right. Ponytail points towards Dave who replies from off-panel to the right.]<br />
:Ponytail: And Dave, who has a radar gun, says it's expanding at 85 mph in all directions.<br />
:Dave (off-panel): ''Those galaxies are really booking it!''<br />
:Ponytail: Thanks, Dave.<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Ponytail]]<br />
[[Category:Astronomy]]<br />
[[Category:Physics]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2516:_Hubble_Tension&diff=2180922516: Hubble Tension2021-09-16T05:51:06Z<p>172.70.34.91: Added descriptions.</p>
<hr />
<div>{{comic<br />
| number = 2516<br />
| date = September 15, 2021<br />
| title = Hubble Tension<br />
| image = hubble_tension.png<br />
| titletext = Oh, wait, I might've had it set to kph instead of mph. But that would make the discrepancy even wider!<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by Dave - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
The fact that most galaxies are receeding from us, and that the distance to the galaxy is directly proportional to the speed (as measured by redshift) was discovered in the 1920s by Edwin Hubble and others. This constant of proportionality is known as the Hubble Constant.<br />
<br />
One way of measuring the Hubble Constant is to measure the distance to (relatively) nearby galaxies. Once distance is obtained, speed can be easily obtained by measuring the redshift and thus the Hubble Constant calculated. Measuring the distance turns out to be feindishly difficult because a distant bright star looks the same as a dim star that is closer.<br />
<br />
In practice, astronomers have a number of ways of measuring distance that work at different scales, and they can be built upon to measure distance to far away galaxies. This is known as the cosmological distance ladder. <br />
<br />
The first rung is parallax. As the Earth orbits around the Sun, nearby stars appear to move slightly relative to distant stars; a star that moves by one second of arc is said to have a distance of 1 Parsec, or about 4 light years. <br />
<br />
The next rung is Cepheid variables, which periodically brighten and dim. The frequency of variation is related to the absolute brightness of the star, and thus by comparing the absolute to the relative brightness the distance can be measured. <br />
<br />
The final rung is Type 1a Supernovae, which occur when an accreting white dwarf exceeds 1.4 solar masses. Because the initial mass is always identical, the absolute brightness of the explosion is as well, so the distance can be calculated.<br />
<br />
Putting these together, the best measurement of the Hubble Constant is 73 km/s/Mparsec.<br />
<br />
This is in conflict with the other main way of measuring the Hubble Constant, using the Cosmic Microwave Background radiation, which yields a value of 68 km/s/Mparsec. The difference is statistically significant, and well outside the error bounds of each measurement.<br />
<br />
Since the CMB technique relies on our understanding and assumptions about the early universe, as well as on the cosmological effects of General Relativity on large scales, if this discrepancy proved real it could be the gateway to new discoveries in cosmology, gravity, and possibly shed light on the origin of the universe and a theory of everything. Cosmologists got quite excited about this. It might also be that there was a previously unaccounted-for error in any of the rungs of the cosmological distance ladder, and that once that is fixed, the two results will be consistent.<br />
<br />
This also disagrees with Dave.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
Cueball and Ponytail are walking.<br />
<br />
Physicist [Ponytail]: There are three main estimates of the universe's expansion rate and they all disagree.<br />
<br />
Physicist [Ponytail]: Measurements of star distances suggest [that] the universe is expanding at 73 km/s per megaparsec.<br />
<br />
Physicist [Ponytail]: Measurements of the cosmic microwave background suggest [that the universe is] expanding at 68 km/s per megaparsec.<br />
<br />
Physicist [Ponytail]: And Dave, who has a radar gun, says it's expanding at 85 [miles per hour] in all directions. <br><br />
Dave [off-screen]: Those galaxies are really booking it. <br><br />
Physicist [Ponytail]: Thanks, Dave.<br />
<br />
Title text: Oh, wait, I might've had it set to kph instead of mph. But that would make the discrepancy even wider!<br />
{{comic discussion}}</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2511:_Recreate_the_Conditions&diff=217663Talk:2511: Recreate the Conditions2021-09-05T14:31:56Z<p>172.70.34.91: </p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Notice that the picture of the palm tree looks kind of like the spray of particles in the first slide. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 05:03, 4 September 2021 (UTC)<br />
:No...? Not at all... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:14, 5 September 2021 (UTC)<br />
<br />
One goal of particle colliders such as LHC at CERN is to recreate conditions similar to those few seconds after the Big Bang, but they have still not destroyed the earth.{{unsigned|162.158.129.67|06:08, 4 September 2021}}<br />
:That we know of... [[Special:Contributions/162.158.159.71|162.158.159.71]] 12:41, 4 September 2021 (UTC)<br />
::Well we may not know their goals... But if you read this they have not (yet) destroyed the Earth --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:14, 5 September 2021 (UTC)<br />
:::You cannot rule out that we are speaking(/typing), unknowingly, from the afterlife/data-backup-and-simulation to which we (or, possibly, each still cogent individual, with or without a solipstic-inclination to each (my!) personal experience) are treated to the 'continuation' of our existence(s) due to something that happens at the very moment the false vacuum decays, or whatever.<br />
:::(Or, on another track, we have irretrievably and inevitably doomed the Earth already, it is just a convenient fiction that it has not ''yet'' concluded its nigh-on imminent final destruction, having been already seeded by enough nanosingularities/strange-particles/antichronons/cavorite/Vogons.)<br />
::: ((Or both!)) :P [[Special:Contributions/172.70.34.91|172.70.34.91]] 14:31, 5 September 2021 (UTC)<br />
<br />
I believe one of Tom Scott's oldest videos is about a pina collider that he built. [[Special:Contributions/172.70.130.211|172.70.130.211]] 13:24, 4 September 2021 (UTC)<br />
:Yes, [https://www.youtube.com/watch?v=rbenrpfuxHs Here it is] [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 16:33, 4 September 2021 (UTC)<br />
<br />
People designing particle accelerators have observed that one problem with new accelerators is attracting qualified people to come work there. This was a particular problem with {{w|FRIB}} in Michigan, due to the weather/climate. The obvious solution is to plan to build an accelerator in a place to which lots of people would like to relocate, e.g., {{w|Tahiti}}. Sorry, I can't find this in print; it was just less-than-fully-serious conversations at conferences.[[Special:Contributions/172.68.141.225|172.68.141.225]] 01:13, 5 September 2021 (UTC)<br />
:I doubted that there are so many particle accelerators that scientists would be choosy about the location and wouldn't jump at any chance they had. Then I found that there are over 30,000 particle accelerators in the world [https://www.symmetrymagazine.org/article/april-2014/ten-things-you-might-not-know-about-particle-accelerators Ten Things You Didn't Know About Particle Accelerators] [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 02:37, 5 September 2021 (UTC)<br />
<br />
This comics resembles final picture and title text from https://what-if.xkcd.com/129/. [[Special:Contributions/172.68.244.173|172.68.244.173]] 11:27, 5 September 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2511:_Recreate_the_Conditions&diff=217662Talk:2511: Recreate the Conditions2021-09-05T14:31:23Z<p>172.70.34.91: </p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Notice that the picture of the palm tree looks kind of like the spray of particles in the first slide. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 05:03, 4 September 2021 (UTC)<br />
:No...? Not at all... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:14, 5 September 2021 (UTC)<br />
<br />
One goal of particle colliders such as LHC at CERN is to recreate conditions similar to those few seconds after the Big Bang, but they have still not destroyed the earth.{{unsigned|162.158.129.67|06:08, 4 September 2021}}<br />
:That we know of... [[Special:Contributions/162.158.159.71|162.158.159.71]] 12:41, 4 September 2021 (UTC)<br />
::Well we may not know their goals... But if you read this they have not (yet) destroyed the Earth --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:14, 5 September 2021 (UTC)<br />
::You cannot rule out that we are speaking(/typing), unknowingly, from the afterlife/data-backup-and-simulation to which we (or, possibly, each still cogent individual, with or without a solipstic-inclination to each (my!) personal experience) are treated to the 'continuation' of our existence(s) due to something that happens at the very moment the false vacuum decays, or whatever.<br />
:::(Or, on another track, we have irretrievably and inevitably doomed the Earth already, it is just a convenient fiction that it has not ''yet'' concluded its nigh-on imminent final destruction, having been already seeded by enough nanosingularities/strange-particles/antichronons/cavorite/Vogons.)<br />
::: ((Or both!)) :P [[Special:Contributions/172.70.34.91|172.70.34.91]] 14:31, 5 September 2021 (UTC)<br />
<br />
I believe one of Tom Scott's oldest videos is about a pina collider that he built. [[Special:Contributions/172.70.130.211|172.70.130.211]] 13:24, 4 September 2021 (UTC)<br />
:Yes, [https://www.youtube.com/watch?v=rbenrpfuxHs Here it is] [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 16:33, 4 September 2021 (UTC)<br />
<br />
People designing particle accelerators have observed that one problem with new accelerators is attracting qualified people to come work there. This was a particular problem with {{w|FRIB}} in Michigan, due to the weather/climate. The obvious solution is to plan to build an accelerator in a place to which lots of people would like to relocate, e.g., {{w|Tahiti}}. Sorry, I can't find this in print; it was just less-than-fully-serious conversations at conferences.[[Special:Contributions/172.68.141.225|172.68.141.225]] 01:13, 5 September 2021 (UTC)<br />
:I doubted that there are so many particle accelerators that scientists would be choosy about the location and wouldn't jump at any chance they had. Then I found that there are over 30,000 particle accelerators in the world [https://www.symmetrymagazine.org/article/april-2014/ten-things-you-might-not-know-about-particle-accelerators Ten Things You Didn't Know About Particle Accelerators] [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 02:37, 5 September 2021 (UTC)<br />
<br />
This comics resembles final picture and title text from https://what-if.xkcd.com/129/. [[Special:Contributions/172.68.244.173|172.68.244.173]] 11:27, 5 September 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2511:_Recreate_the_Conditions&diff=2175972511: Recreate the Conditions2021-09-04T04:37:54Z<p>172.70.34.91: </p>
<hr />
<div>{{comic<br />
| number = 2511<br />
| date = September 3, 2021<br />
| title = Recreate the Conditions<br />
| image = recreate_the_conditions.png<br />
| titletext = We've almost finished constructing the piña collider.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a BIG BANG FLAVORED PALM CHUNGUS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
{{comic discussion}}</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=Talk:2509:_Useful_Geometry_Formulas&diff=217503Talk:2509: Useful Geometry Formulas2021-09-02T09:00:19Z<p>172.70.34.91: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
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Area formulas are for 2D object as seen instead of surface of a projected 3D object. Sebastian --[[Special:Contributions/162.158.89.200|162.158.89.200]] 02:36, 31 August 2021 (UTC)<br />
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The "decorative stripes and dotted lines" are the parts of the diagrams that are intended to indicate the third dimension. The conceit of the comic is that these are superfluous. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 02:56, 31 August 2021 (UTC)<br />
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Ca someone explain how the last one works? [[User:GcGYSF(asterisk)P(vertical line)e|GcGYSF(asterisk)P(vertical line)e]] ([[User talk:GcGYSF(asterisk)P(vertical line)e|talk]]) 04:28, 31 August 2021 (UTC)<br />
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: ''bh'' is the area of the front face. The top face is a parallelogram with sides ''d'' and ''b'', with an angle of ''θ'' between them, so its area is ''d b sin(θ)''. The right face is a parallelogram with sides ''d'' and ''h'', with an angle of ''90º - θ'' between them, so its area is ''h d sin(90º - θ) = h d cos(θ)''. So the area of the whole picture is ''bh + d b sin(θ) + d h cos(θ)''.<br />
: --[[Special:Contributions/172.68.24.165|172.68.24.165]] 04:46, 31 August 2021 (UTC)<br />
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:: In case you don't know the area of a parallelogram by heart, you can read d b sin(θ) as b * d sin(θ), where d sin(θ) is the height of the parallelogram; if you cut the right corner of the parallelogram off and add it on the left, you get a rectangle where the bottom side is b and the height is that d sin(θ), so it works out. The other parallelogram's area is h * d cos(θ), with the same reasoning. [[Special:Contributions/162.158.90.241|162.158.90.241]] 05:00, 31 August 2021 (UTC)<br />
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Funnily enough, both this comic and [[2506]] are about projection. [[User:CRLF|CRLF]] ([[User talk:CRLF|talk]]) 05:11, 31 August 2021 (UTC)<br />
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: I had considered working that into the explanation, but that needs to account for the fact that the indicated measurements (e.g. the angle θ) have to be read in 2D, not in 3D and projected. But it would be correct to say that the 2D shapes are projections of simple 3D objects. [[Special:Contributions/162.158.90.149|162.158.90.149]] 05:23, 31 August 2021 (UTC)<br />
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: Between this, [[2506]], and all the ones about Mercator and other map projections ... "projection" is a very large word in Randall's brain's word cloud. [[Special:Contributions/172.69.63.8|172.69.63.8]] 15:29, 31 August 2021 (UTC)<br />
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:: Feels to me like every comic since 2500 could be tagged "projection" in one sense of the word or another. --[[Special:Contributions/172.69.69.225|172.69.69.225]] 21:55, 31 August 2021 (UTC)<br />
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;Does the bottom-left formula have a mistake?</s><br />
It seems like the bottom-left formula should be ''A''=''d''(''πr''+''h'') rather than ''A''=''d''(<sup>''πr''</sup>/<sub>2</sub>+''h''), because there are two half-ellipses that add up to a complete ellipse. Am I missing something? (This doesn't ''seem'' like an extra joke, does it?) [[Special:Contributions/162.158.106.179|162.158.106.179]] 05:28, 31 August 2021 (UTC)<br />
: No, it's correct. ''d'' is all of the major axis, not just half, so we have to divide that by ''2''. [[Special:Contributions/162.158.92.83|162.158.92.83]] 05:51, 31 August 2021 (UTC)<br />
:: Oh, right; good call! [[Special:Contributions/162.158.106.179|162.158.106.179]] 06:49, 31 August 2021 (UTC)<br />
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;Does the top-right formula have a mistake?<br />
I think it should be in brackets, the top triangle area needs the ''<sup>1</sup>/<sub>2</sub>'' also, so it should be: ''A''=''<sup>1</sup>/<sub>2</sub>(πab + bh)''<br />
:No, it's correct. The bottom is a half ellipse, with area ''1/2 π a b'', and the top is a triangle with base ''2 b'' and height ''h'', so its area is ''1/2 2b h = bh''. The total area is ''1/2 π a b + b h''.<br />
--[[Special:Contributions/172.68.25.144|172.68.25.144]] 06:49, 31 August 2021 (UTC)<br />
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;3D formulae for reference:<br />
''4πr^2''<br />
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''πb(a+√(b^2+h^2))'' if a=b<br />
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''πr(2r+h)''<br />
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''2(bd+bh+dh)''<br />
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[[Special:Contributions/162.158.107.80|162.158.107.80]] 09:54, 31 August 2021 (UTC)<br />
:It would be clarifying to add these to the comic, but of course they are flagrantly wrong. [[User:Baffo32|Baffo32]] ([[User talk:Baffo32|talk]]) 09:57, 31 August 2021 (UTC)<br />
::Surely ripe for a table, in place of much of the longhand paragraph spiel (which could be kept, but simpler for just the narrative but otherwise non-technical details)... "Shape (2D)", "Area", "Pretended Shape (3D)", "Surface Area", "Volume", ¿"Notes"? (Not sure about specific Notes, some things could/should be said below the formulae/descriptions in the relevent cell to which that matters, in special cases where necessary, which might be better than a Notes either empty or jammed up with all the combined row-specific corollaries, etc, that I can imagine.) Anyway, an idea. [[Special:Contributions/141.101.76.11|141.101.76.11]] 11:56, 31 August 2021 (UTC)<br />
:::I think the formulas are correct. Those given should be from the text book, not for those with ellipse bases. Someone has put a lot of work into giving these complicated formulas for the cone and cylinder. But I think that is overkill. I have added to the explanation the simple versions before, and would suggest deleting the complicated, which was never the intention of either text book or Randall! ;-)--[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:36, 31 August 2021 (UTC)<br />
: Surface area. Not volume. My bad. I usually consider volume associated with pics like like that. Don't use surface area much. [[User:Baffo32|Baffo32]] ([[User talk:Baffo32|talk]]) 22:22, 1 September 2021 (UTC)<br />
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add an extra edited image that is the comic without dotted lines to make it easier to see the 2d shapes? [[Special:Contributions/172.69.71.177|172.69.71.177]] 12:46, 31 August 2021 (UTC)Bampf<br />
:And an animated GIF of the 3D solid objects rotating to show their real shapes. At different speeds. If you have the time. :-) Robert Carnegie rja.carnegie@gmail.com [[Special:Contributions/141.101.76.11|141.101.76.11]] 16:31, 31 August 2021 (UTC)<br />
: Image here: https://i.imgur.com/dq7VmnK.png Editing done myself, feel free to upload it to this wiki if you have an account on this wiki. :) --[[Special:Contributions/162.158.88.29|162.158.88.29]] 17:22, 1 September 2021 (UTC)<br />
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Please do check my (additional) changes to the bottom-right item (hexagon-cum-prism) in both main and transcript texts. As hinted in my edit notes, cos-theta is important because the skewed tetrahedron (rhomboid, whether in plan or the true area of the 'fake' perspective) is not d*b in area. The fact that without the theta it would look like a standard oblique orthographic projection with entirely right-angled corners is perhaps part of the (intended?) confusion, although we can probably assume that all unmarked (and, of course, uncongruent/uncomplimentary) angles are 90° so that it isn't a full on parallelepiped with an additional phi-angle on an adjacent face and a complicated third dependent-angle somewhere upon the remaining face-plane. As such, I put in the cosine element to both the 3d surface formula (it only affects the bd-shape, the both of them) and the 3d volume (from this shape, extrudes without further adjustment straight up the h-axis), but I ''always'' have to second guess if I've done this simple bit of trig right, it seems, even though I should know better and just trust to SOHCAHTOA... ;) [[Special:Contributions/162.158.158.146|162.158.158.146]] 13:24, 31 August 2021 (UTC)<br />
:(Case in point: I thought I'd added cosines, and I'd put sines ''anyway'', when fussing about copying the clipboarded theta-character into the right place! Re-read, seen, corrected(?) this myself. Unless I thought I was was wrong; but I was wrong, I was right!) [[Special:Contributions/162.158.155.145|162.158.155.145]] 13:33, 31 August 2021 (UTC)<br />
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I believe both of those prism formulas should use sine theta. If theta is ninety degrees, then sine theta will be 1 (thus reducing to the rectangular case), whereas cosine of 90 degrees is zero.[[User:Tovodeverett|Tovodeverett]] ([[User talk:Tovodeverett|talk]]) 15:19, 31 August 2021 (UTC)<br />
:You're right (me again, from just above), I was rushed and ''had'' been right first time, I realised while I was off-grid and it was nagging away at the back of my head. I'm better on paper (or when I can sanity-test real code, but for some reason tapping it in like this just screws my mind up, taking away/inverting my technical ability and reason. (I blame the microwaves emitting from my tablet... pass the tinfoil hat!) [[Special:Contributions/162.158.158.178|162.158.158.178]] 16:29, 31 August 2021 (UTC)<br />
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Unconvinced by the cone! The equation shown, is correct for an isosceles triangle with a half-ellipse on its base. But that shape has 'corners' where the sides meet that half-ellipse. In a 3D projected view of an actual cone, the sides will meet the base ellipse at a tangent, meaning that it is more than a half-ellipse. But I suppose it's close enough as an approximation...[[Special:Contributions/172.69.55.131|172.69.55.131]] 15:57, 1 September 2021 (UTC)<br />
: I verified your claim by imagining the surface of the cone as formed by a set of lines extending from the different points on the ellipse to a single fixed point at the tip. No matter where you put that tip point, the outermost lines seem tangent to the ellipse. Seems it works for both perspective and orthographic projections. Updated the explanation. Randall's formula is incorrect, especially for very short cone projections. [[User:Baffo32|Baffo32]] ([[User talk:Baffo32|talk]]) 22:46, 1 September 2021 (UTC)<br />
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; It's 3am (okay 5am) and I made it really long!<br />
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I just followed the directions in the "incomplete" which said to add in explanations of the formulae ... Please feel free to edit to take out redundancy. However I did add in the following explanations:<br />
- the fact that the formula in the third figure is actually the same as the cross-section represented by the ellipse, which is why you may not get the joke after reading the first picture;<br />
- the use of 'd', 'r' and 'h' in the third figure, which adds to the confusion as they imply "diameter", "radius" and "height"<br />
- the fact that the area calculations must take into account the overlapping shapes (there were previously references to "semi-ellipses" which are extrapolations, not what's drawn there)<br />
Haven't yet done the last figure<br />
- pretty sure 'b' 'd' and 'h' are for 'breadth', 'depth' and 'height' and while 'height' is also used for 2D rectangles, 'breadth' less so in maths textbooks (usually 'width')<br />
- whoever pointed out that there is a theta as well, pretty sure it's only there because it's necessary for the area calculation, as 'depth' only really applies as labelled to rectangular prisms - if the base were not rectangular, 'd' would not be equal to the 'depth'<br />
Will try to come back later and shorten... [[Special:Contributions/162.158.166.40|162.158.166.40]] 18:56, 1 September 2021 (UTC)<br />
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Someone [https://www.explainxkcd.com/wiki/index.php?title=2509:_Useful_Geometry_Formulas&diff=217438&oldid=217434 thought that] "formulae" was a typo for "formulas" (which it might easily be, on a QWERTY or similar layout). Not going to revert, but note that (for a mathematical formula, if perhaps not a chemical one/etc, but there's plenty of mixed use) this is actually quite correct. If it were up to me alone (I didn't write that one, orother mentions like in the above Talk contribution), for the record, I'd probably have used "formulæ" myself. ;) [[Special:Contributions/162.158.155.145|162.158.155.145]] 20:28, 1 September 2021 (UTC)<br />
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If you don't assume that the bottom right figure is 3D, what's the justification for projecting upward and assuming that the angle theta is also the angle of the top parallelogram? [[User:Arl guy|Arl guy]] ([[User talk:Arl guy|talk]]) 02:25, 2 September 2021 (UTC)<br />
:If you assume that the two rectangles have equal width and height, then it can be mathematically proven that the angles must be equal (probably using congruent triangles). However this assumption is not stated on the figure. That said, you would make the same assumption for the 3D figure, along with a whole bunch of other assumptions of course.[[Special:Contributions/172.70.147.23|172.70.147.23]] 06:31, 2 September 2021 (UTC) Edit: The two rectangles must have equal width and height to make the rest of the shapes parallelograms in the first place. If they aren't identical you get trapezoids all round and possibly a bunch of different angles. [[Special:Contributions/172.70.143.22|172.70.143.22]] 06:43, 2 September 2021 (UTC)<br />
:There's always many possible {{w|Ames room|unindicated perspective tricks}} (or axonometric/othographic ones, as might be more appropriate) in which the components of lines and relationships towards/away from the viewer are non-zero (or {{w|Penrose triangle|not non-zero in the way expected}}). Various of the shapes involved could be infinitely warped with leans, curves or even highly inflected wiggles to allow ''some'' 'as expected' profile even as others that should be connected are not. (Though it would make the surface 'planes' warped and distorted, even more against the conventions of wireframe diagrams.)<br />
:Because of dependencies, as the theta moves the other similar angles ''might'' be thetas too, or they could be kept as RAs and (?)three ''other'' chosen angles could be distorted (in or out of the page, by a calculable and entirely derivative amount) to compensate. Or, like the Triangle illusion, there's overlaid duplicate edges with not all/any vertices actually being the same, just in the same illustrated place. (Again, making a mockery of the 'simple' diagram, but we're already way past that. ;) ) [[Special:Contributions/162.158.155.247|162.158.155.247]] 08:56, 2 September 2021 (UTC)</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2502:_Every_Data_Table&diff=2165542502: Every Data Table2021-08-14T12:24:36Z<p>172.70.34.91: </p>
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<div>{{comic<br />
| number = 2502<br />
| date = August 13, 2021<br />
| title = Every Data Table<br />
| image = every data table.png<br />
| titletext = "I'm hoping 2022 is relatively normal because I don't know what symbol comes after the asterisk and the dagger."<br />
| imagesize =<br />
}}<br />
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==Explanation==<br />
{{incomplete|Created by a TRIPLE DAGGER. Do NOT delete this tag too soon.}}<br />
This comic is another entry in a [[:Category:COVID-19|series of comics]] related to the {{w|COVID-19 pandemic|2020-21 pandemic}} of the {{w|SARS-CoV-2}} virus, which causes {{w|COVID-19}}.<br />
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The COVID pandemic has had a large impact on the entire world and one way this can be seen is through strange stats resulting from the effects of the pandemic. Various statistics such as employment statistics, spending power, holiday miles, pet ownerships, births (or at least conceptions) and &mdash; naturally &mdash; deaths may have been either grossly suppressed/increased for the majority of 2020, and for 2021 may have hardly recovered, partially recovered, renormalised, bounced back with a vengeance or be over-compensated for in the effort to catch up.<br />
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It is hard to know what 2022 might be like. Nothing (at the time of this comic being published) is exactly back to normal and proper recovery or the resulting compensatory readjustment may not have concluded in time for 2022 to reflect the trends expected based upon pre-2020 figures, and the additional further years that future statistics will record.<br />
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As an example, the cycles of Summer and Winter Olympics/Paralympics has been disrupted due to the 2020 Summer Olympics being postponed to 2021, thus causing the next Winter Olympics to be only 1 year away (in 2022) and the next Summer Olympics/Paralympics to be 3 years away (in 2024). This has not occurred since the 1990s (when both of the Winter Games were shifted away from the Summer Games' years), or the 1940s (the last major interruption in the main Summer Olympic cycle).<br />
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Sometimes punctuation such as an asterisk (*) or a dagger (†, also called an obelisk) is used to denote an unusual entry in a table to be explained in a footnote with a matching symbol. Common symbols that are used if the first two are taken include multiple symbols (such as †† or ***), or a series of further symbols such as a double dagger (‡), the section symbol/silcrow (§), the parallel/double-pipe (‖) and the paragraph symbol/pilcrow (¶). Alternately you can start and continue with superscript numbers (¹, ², ³ ...), especially when you expect to commonly need {{w|Terry Pratchett|multiple}} and/or {{w|Randall Munroe|nested}} footnotes on each page, or gather them as endnotes, a whole chapter at a time.<br />
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The author, however, seems to have forgotten the potential monkey's paw nature of his wish. Relative is a relative term. It could well be that the whole pandemic thing becomes the new normal, thus removing the necessity of using symbols to delineate such years.<br />
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== Transcript ==<br />
<br />
:2017........ (scribble)<br />
:2018....... (scribble)<br />
:2019....... (scribble)<br />
:2020*...... (scribble)<br />
:2021<span style="font-family: serif;"><sup>†</sup></span>...... (scribble)<br />
:2022....... (scribble)<br />
:2023....... (scribble)<br />
:2024....... (scribble)<br />
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:[Caption under the panel:]<br />
:Every data table from now on<br />
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{{comic discussion}}<br />
<br />
[[Category:COVID-19]]<br />
[[Category:Statistics]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2496:_Mine_Captcha&diff=2158622496: Mine Captcha2021-08-01T01:07:00Z<p>172.70.34.91: grammar</p>
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<div>{{comic<br />
| number = 2496<br />
| date = July 30, 2021<br />
| title = Mine Captcha<br />
| image = mine_captcha.png<br />
| titletext = This data is actually going into improving our self-driving car project, so hurry up--it's almost at the minefield.<br />
}}<br />
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==Explanation==<br />
{{incomplete|Created by a LIVE MINEFIELD WITH HUGE NUMBER CUBES SKEWED AROUND. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}<br />
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This comic, like [[1897: Self Driving]], references the approach of using {{W|CAPTCHA}} inputs to solve problems, particularly those involving image classification that computers need to know how to solve. Specifically, it reflects {{W|reCAPTCHA}} v2's fallback puzzle which is based on identifying road features and vehicles. A reCAPTCHA puzzle might ask a user to "check all squares containing a STOP SIGN." in order to help train systems that must do it automatically.<br />
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This is actually a trick captcha. It asks to click on '''pictures''' of mines. There are no pictures of mines in the captcha, there are only numbers and empty fields. So this is trivially solvable by doing nothing and all this talk about Minesweeper solving below is moot but interesting to read nonetheless.<br />
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{{w|Minesweeper (video game)|Minesweeper}} is a logic puzzle game where the player must uncover tiles in a grid by clicking on them. Some of the tiles contain "mines" such that revealing those means immediate defeat. When uncovering a tile without a mine it shows how many of the (up to 8) adjacent tiles contain a mine or, if the tile has no neighbouring mines, it automatically and recursively reveals every neighbouring tile as far as all numbered 'clue' tiles. By reference to the indications provided by those numbers, a player (optionally, but typically) will mark those that they identify in their efforts to succesfully reveal all unmined locations and win the game having tripped none of the mines.<br />
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This comic uses the game to create a CAPTCHA that ironically asks the user to "Click all the pictures of MINES", the opposite of the traditional goal, hence the title Mine Captcha.<br />
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This mine CAPTCHA might be considered awkward for a variety of reasons. Firstly, unlike image recognition, which is a natural biological and developmental skill, humans don't naturally learn the tricks needed to win at Minesweeper. It is a logic game {{w|Microsoft Minesweeper|being bundled with Microsoft Windows}} which provides little obvious instruction and often it was bored people launching the program who would start randomly clicking on squares unsure of what they are supposed to do. Those who perservere get to learn the tricks and traps, but not everyone will do that and thus also understand how to adequately solve the CAPTCHA.<br />
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Secondly, clicking on the squares that contain mines is the opposite of what you do in actual Minesweeper, and players who are sufficiently familiar with the game might get tripped up by muscle memory, putting you at a disadvantage no matter your skill level with the original game.<br />
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Thirdly, minesweeper involves a certain degree of luck. While logical skills are important, there are possible instances (increasingly so as the chosen difficulty level is increased) where the numbers do not provide adequate information to confidently assure it is in a single specific square, leaving even expert players to have to guess and hope they do not trip on one the more unlikely (but possible) final mines after a lot of other mental work done to successfully clear and confirm the rest of the map. If luck plays any part in the CAPTCHA, this would increase false negatives in human detection. (The implication of most logic pizzles is that the problem given to the user is of a state where only one possible solution exists as an answer, but the conceipt of this one is that the solution is ''not'' known by the puzzle-creator.)<br />
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Fourthly, solving a game of Minesweeper is usually (although not in this case) impossible without clicking more of the empty gray squares to reveal enough info to figure out which ones have mines on them.<br />
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Fifthly, a CAPTCHA is meant to be a challenge designed to be solvable by humans but not computers; Minesweeper would be easily solvable by an AI (assuming no ambiguity) as it is, at its core, a logic puzzle, and the squares are simple shapes with solid-color backgrounds and thus relatively easy for an AI to process.<br />
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Regarding the game itself, 6 of the 16 tiles hae a colored number, in blue for the three number ones, green for a single instance of two, and red for the two number threes. Given the current board configuration, one can deduce that there are four mines (in squares A2, B2, B3 and D3, where letters (numbers) mark columns (rows)), see [[#Trivia|trivia section]]. For example, there are two mines within the squares A2,B1,B2, as signified by the 2 in A1, but only one of those can be in B1 or B2 (because of the 1 in C1). Therefore, A2 has to be a mine.<br />
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Each number is shown in a different font and style. This follows a technique used in CAPTCHAs that display text in various styles, often distorted, and ask the user to type in the displayed characters. <br />
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<pre><br />
A B C D<br />
<br />
1 2 . 1 .<br />
2 * * 3 .<br />
3 3 * . *<br />
4 . 1 . 1<br />
</pre><br />
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The title text is similar to [[1897: Self Driving]] where the CAPTCHA solver is asked to answer quickly, parodying the current tendency for CAPTCHAs to apparently be used as training data to teach AI how to correctly identify road hazards by instead suggesting the CAPTCHA offloads the task to a human instead. In this case the car is apparently driving into a minefield and can only avoid the mines if the user solves this CAPTCHA fast enough. Where the first would be plausible, although very dangerous, this time it hinges on ridiculous, as real minefields usually do not have large numbers indicating which of the surrounding land contains mines{{citation needed}}.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
[A "CAPTCHA" box.]<br />
<br />
To proceed, click<br>all the pictures of<br>MINES<br />
<br />
[A 4 by 4 ''Minesweeper'' field, with some cells revealed with numbers. Each number is drawn in a different font/style.]<br />
<br />
<pre><br />
2 . 1 .<br />
. . 3 .<br />
3 . . .<br />
. 1 . 1<br />
</pre><br />
<br />
==Trivia==<br />
*The solved version of the puzzle showing where the mines are in this comic, and thus the fields that needs to be pushed in this Captcha to prove you are human:<br />
:[[File:2946_Mine_Captcha_With_Bombs.png]]<br />
*The solved puzzle as it would look if played as a real minesweeper game, except the mines would be represented by flags. (The empty square top right corner has 0 bombs next to it. This is not written in the game but indicated as this field has been pushed down):<br />
:[[File:2946_Mine_Captcha_Solved.png]]<br />
*The original game can be played here: [https://minesweeper.online/ World of Minesweeper]<br />
**It is possible to build a 4x4 CAPTCHA game there:<br />
:[[File:2946_Mine_Captcha_Example_of_4x4_game.png]]<br />
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{{comic discussion}}<br />
<br />
[[Category:CAPTCHA]]<br />
[[Category:Self-driving cars]]<br />
[[Category:Comics with color]]</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2487:_Danger_Mnemonic&diff=2148502487: Danger Mnemonic2021-07-10T04:23:39Z<p>172.70.34.91: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 2487<br />
| date = July 10, 2021<br />
| title = Danger Mnemonic<br />
| image = danger_mnemonic.png<br />
| titletext = It's definitely not the time to try drinking beer before liquor.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a DRUNKEN SAILOR'S POISON IVY SNAKE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}<br />
<br />
This is a mash-up of three different common sayings: "red touches yellow, dead fellow. Red touches black, happy Jack," "leaves of three, leave them be," and "red sky at morning, sailors take warning. Red sky at night, sailor's delight."<br />
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The adult refers to three different sayings that remind people how to recognize dangerous things or situations. If all are true at once, then things must be especially bad. The sayings are:<br />
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'''Red touches yellow, kills a fellow.''' This is a saying for how to recognize a venomous coral snake, which has red, black, and yellow stripes, which the red and yellow stripes adjacent. A nonvenomous king snake also has red, black, and yellow stripes, but the black stripes separate the red and yellow ones.<br />
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'''Leaves of three, leave them be''' is used to identify poison ivy from its many lookalikes, such as the Virginia creeper in https://xkcd.com/443/.<br />
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'''Red sky at morning, sailor take warning. Red sky at night, sailor's delight.''' This is a bit of folklore indicating that the weather at sea is likely to be worse during the day if the sunrise was strongly red.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
{{comic discussion}}</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2487:_Danger_Mnemonic&diff=2148482487: Danger Mnemonic2021-07-10T04:21:55Z<p>172.70.34.91: /* Explanation */</p>
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<div>{{comic<br />
| number = 2487<br />
| date = July 10, 2021<br />
| title = Danger Mnemonic<br />
| image = danger_mnemonic.png<br />
| titletext = It's definitely not the time to try drinking beer before liquor.<br />
}}<br />
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==Explanation==<br />
{{incomplete|Created by a DRUNKEN SAILOR'S POISON IVY SNAKE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}<br />
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This is a mash-up of three different common sayings: "red touches yellow, dead fellow. Red touches black, happy Jack," "leaves of three, leave them be," and "red sky at morning, sailors take warning. Red sky at night, sailor's delight."<br />
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The adult refers to three different sayings that remind people how to recognize dangerous things or situations. If all are true at once, then things must be especially bad. The sayings are:<br />
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- '''Red touches yellow, kills a fellow.''' This is a saying for how to recognize a venomous coral snake, which has red, black, and yellow stripes, which the red and yellow stripes adjacent. A nonvenomous king snake also has red, black, and yellow stripes, but the black stripes separate the red and yellow ones.<br />
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-"leaves of three, leave them be" is used to identify poison ivy from its many lookalikes, such as the Virginia creeper in https://xkcd.com/443/.<br />
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-'''Red sky at morning, sailor take warning. Red sky at night, sailor's delight.''' This is a bit of folklore indicating that the weather at sea is likely to be worse during the day if the sunrise was strongly red.<br />
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==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
{{comic discussion}}</div>172.70.34.91https://www.explainxkcd.com/wiki/index.php?title=2487:_Danger_Mnemonic&diff=2148442487: Danger Mnemonic2021-07-10T04:15:22Z<p>172.70.34.91: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 2487<br />
| date = July 10, 2021<br />
| title = Danger Mnemonic<br />
| image = danger_mnemonic.png<br />
| titletext = It's definitely not the time to try drinking beer before liquor.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a DRUNKEN SAILOR'S POISON IVY SNAKE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}<br />
<br />
This is a mash-up of three different common sayings: "red touches yellow, dead fellow. Red touches black, happy Jack," "leaves of three, leave them be," and "red in the morning, sailor's warning. Red at night, sailor's delight."<br />
<br />
The adult refers to three different sayings that remind people how to recognize dangerous things or situations. If all are true at once, then things must be especially bad. The sayings are:<br />
<br />
- '''Red touches yellow, kills a fellow.''' This is a saying for how to recognize a venomous coral snake, which has red, black, and yellow stripes, which the red and yellow stripes adjacent. A nonvenomous king snake also has red, black, and yellow stripes, but the black stripes separate the red and yellow ones.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
{{comic discussion}}</div>172.70.34.91