explain xkcd - User contributions [en]

2490: Pre-Pandemic Ketchup

2025-05-04T17:42:33Z

Nico31415926: Undo vandalism. I don't care what you personally think about the pandemic; it's not relevant to the actual article.

{{comic
| number = 2490
| date = July 16, 2021
| title = Pre-Pandemic Ketchup
| image = pre_pandemic_ketchup.png
| titletext = I wonder what year I'll discard the last weird food item that I bought online in early 2020.
}}

==Explanation==
This comic is another in a [[:Category:COVID-19|series of comics]] related to the {{w|COVID-19 pandemic}}.

Just like [[2474: First Time Since Early 2020]], [[Randall]] compares the pre-pandemic life and the post-pandemic life in this comic. Life has changed dramatically due to the COVID-19 pandemic and the subsequent lockdowns and restrictions by governments around the world.

In this comic, [[Cueball]] bought a bottle of ketchup before the pandemic and they have not bought that kind of ketchup since, possibly due to supply chain disruptions or that brand not being available to order online. It may be a reference to the shortage of ketchup packets caused by an increase in takeout orders and restaurants replacing the ketchup bottle on the table with single serving units.{{Dubious}} Cueball is now cleaning out his cupboard, perhaps as a form of "pandemic spring cleaning" to make way for the future, and considers throwing it away. An offscreen character encourages him to toss it.

In the title text, Cueball (or possibly [[Randall]]) is wondering in which year he would discard the last weird food item that he bought online in early 2020. If he's going for the [[Expiration Date High Score]] to beat [[Megan]]'s high score of 24.3, he should probably wait until 2045 or so.

==Transcript==
:[Cueball is standing in a kitchen, looking at bottle with label which he is holding in his hand. He is talking to a person off-panel behind him, who replies. There is a cupboard above him, with stuff protruding from the shelves. Below that is a counter, with a drawer and a cupboard. There is an bottle with fluid, a can and a jar on top. Only the latter two has labels.]
:Cueball: Oh wow, pre-pandemic ketchup!
:Cueball: We haven't bought this kind since before.
:Cueball: I'm gonna toss it.
:(off-screen): Eww, yes.

:[Caption below the panel:]
:Spring 2020 forms a weird dividing line in my kitchen.

{{comic discussion}}

[[Category:COVID-19]]
[[Category:Comics featuring Cueball]]
[[Category:Food]]

3084: Unstoppable Force and Immovable Object

2025-05-04T17:40:28Z

Nico31415926: Fix vandalism

{{comic
| number = 3084
| date = May 2, 2025
| title = Unstoppable Force and Immovable Object
| image = unstoppable_force_and_immovable_object_2x.png
| imagesize = 297x379px
| noexpand = true
| titletext = Unstoppable force-carrying particles can't interact with immovable matter by definition.
}}

==Explanation==
{{incomplete|This page was created by an INFINITE MASS, MOST COMMONLY KNOWN AS "YOUR MOM". Don't remove this notice too soon.}}
An "unstoppable force meeting an immovable object" is a common expression when two things with mutually exclusive properties are forced to interact.

In the comic this is depicted with three drawings, first showing an arrow representing an unstoppable force moving toward an object that is immovable. In the next drawing they meet and the force arrow enters the object. In the final drawing the force arrow is moving past the object that has, of course, not been moved. But the force has also not been stopped. In the caption below [[Randall]] states that he cannot understand why people find this scenario to be tricky.

Most of the time, the expression is just that, an expression, one that is meant to convey there will be a lot of destruction when the two things meet. Sometimes it is a euphemism for more complex things such as people or ideologies (who have contradictory goals and are unwilling or unable to compromise), other times it's an exaggeration for large and powerful forces that are not literally unstoppable but still cause massive damage when they run into each other.

Randall proposes a solution to the paradox: the unstoppable force will not actually interact with the immovable object; the unstoppable force is not stopped and the immovable object is not moved.

An example explanation of this situation is described in a [https://www.youtube.com/watch?v=9eKc5kgPVrA video] by {{w|Minute Physics}}. This comic could actually be said to show what is shown in the video.

Randalls comic makes a play on the word "force" which has different interpretations depending on context. In casual language, an object can be a "force" if it carries enough energy, while to a physicist like Randall it describes a fundamental influence between particles of matter, and not all forces interact with all types of matter, nor ''can'' they be stopped (only depleted, by interaction and dispersion over their effective distance). The humor derives from the differences between the lay-impressions of the scenario and a more technical interpretation, in line with prior [[123: Centrifugal Force|informative comics]] of this ilk.

In the title text Randall makes it clear that unstoppable force-carrying particles do not interact with immovable matter by definition. Thus each of these "impossible" concepts can exist, but since they can never interact, the problem of what will happen when they do, is thus not relevant. In quantum physics all forces are mediated by force-carrying particles, but this is not usually something that is relevant to take into account, when macroscopic objects interact.

==Transcript==
:[In one panel there are three drawings representing the same scenario at three different times. In the first drawing shows a right-pointing arrow ti the left, and a rounded trapezium-like object to the right of the centre. They are both labeled with a line going from the label above down to the objects:]
:Unstoppable Force
:Immovable Object

:[In the second drawing the arrow is shown in the process of moving through the trapezoid, the part of the arrow within the trapezoid is drawn in gray lines.]

:[In the third drawing the arrow is to the right of the trapezoid.]

:[Caption below the panel:]
:I don't see why people find this scenario to be tricky.

{{comic discussion}}

[[Category:Physics]]

3083: Jupiter Core

2025-05-04T17:38:17Z

Nico31415926: Undo vandalism

{{comic
| number = 3083
| date = April 30, 2025
| title = Jupiter Core
| image = jupiter_core_2x.png
| imagesize = 581x443px
| noexpand = true
| titletext = Juno mission data suggests that Jupiter actually contains Matryoshka doll-style nested copies of every other planet in the Solar System.
}}

==Explanation==
{{incomplete|This page was created recently by A PLANET WITH FEELINGS. Don't remove this notice too soon.}}

{{w|Jupiter}} is the largest planet in the {{w|Solar System}}, the fifth planet from the Sun, and the closest-in {{w|gas giant}}. The core of the planet is hidden by an enormous gaseous atmosphere, and this comic lists a number of theories about the structure of that core. The first two are theories that are or have been held by reputable planetary scientists (they can be found in the Wikipedia entry), while the rest are ridiculous ideas from [[Randall]]'s mind.

; Diffuse mix of heavy elements and metallic hydrogen

: This is the current leading theory suggested by measurements taken by NASA's {{w|Juno (spacecraft)|Juno}} probe, a spacecraft orbiting Jupiter since 2016.

; Rocky core with metallic hydrogen mantle

: This was one of the leading proposals prior to the Juno mission.

; Valuable treasure

: Unidentifiable objects that may be gemstones or precious metals, surrounded by dollar signs. May be a reference to the occasionally proposed idea that gas giant cores might be composed of diamond. This idea was mentioned in Arthur C. Clarke's ''{{w|2010: Odyssey Two}}'', and in ''{{w|2061: Odyssey Three}}'' the diamond is found as it was ejected from Jupiter at the end of 2010.

; Emergency backup Earth

: This would be a copy of the Earth that can be put into place once we finish destroying our planet. In popular science Jupiter is often described as a "protector" of Earth since its large gravitational field attracts asteroids that could otherwise hit Earth. This is extending this take to the point where Jupiter has a backup planet in case it fails its mission at protecting the Earth. "Emergency Backup Earth" was previously proposed as an [[1253: Exoplanet Names|exoplanet name]], and was changed to a different exoplanet [[1555: Exoplanet Names 2|later]]. Jupiter's core is not an exoplanet — if anything, it would be a planet, since it is located inside the Solar system.

; Regular planet pretending to be a gas giant to avoid attention

: The joke here is that there is secretly a 'regular' planet (whatever that means — presumably relatively Earth-like) which is shy or secretive and does not want attention, so it pretends to be a gas giant by hiding inside Jupiter. Of course, planets are not shy in real life, as they do not have feelings.{{cn}} The planet inside of Jupiter appears to be Earth-like, and most likely has reasonably advanced life on it, since the large support structures and large surrounding structure itself must presumably have been built by somebody. They're probably quite annoyed at us, considering we've [[1727: Number of Computers|dropped several probes into Jupiter]].

: This might be a reference to [[wikia:w:c:starwars:At Attin|At Attin]], a fictional planet in the {{w|Star Wars}} Cinematic Universe. At Attin is a planet that has an artificially created protective barrier designed to hide it from discovery, so as to conceal its production of [[wikia:w:c:starwars:At Attin Mint|Republic credits]]. The [[wikia:w:c:starwars:Barrier|barrier]] makes the much smaller planet within look like a gas giant and has artificial electrical storms, produced by electrical mines, that destroy any unauthorized ships from approaching the inner planet. At Attin appears in the Star Wars show {{w|Star Wars: Skeleton Crew|Skeleton Crew}} which was released only a few months prior to this comic.

; Hard ball from avocado

: This theory proposes that Jupiter's core is a giant avocado pit, which is the large seed located in the center of an avocado. The outer layers of Jupiter also appear to be the flesh and skin of an avocado in the drawing, thereby creating a very, very large avocado. If the total mass of Jupiter ([https://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html 1.898×1027 kg]) were converted to avocados, as seen in the image, Jupiter would represent 1.81×1018 times Earth's global avocado production in 2023, of approximately [https://www.statista.com/statistics/577455/world-avocado-production 10.5×109 kg].

; Baby Jupiter, still gestating

: This theory proposes that Jupiter is a life form which reproduces by carrying a baby version of itself as its core. While this is obviously not the case, it could provide large hints as to how the solar system originated if true. This also prompts questions as to Jupiter's sex, whether it {{w|Asexual reproduction|reproduces asexually}} and, if not, who the other parent is. Recursion also has interesting effects here, as the small Jupiter must also have a core — it's unclear whether this would contain an even tinier Jupiter, and so on.

:The "theories" of {{w|Immanuel Velikovsky}} propose that Venus came into existence as a cometary body somehow ejected from Jupiter. This body supposedly spent some time bouncing around the solar system by a mechanism similar to quantum mechanics, producing effects described in the Bible, before settling down into its current orbit. (None of this is consistent with our understanding of physics.) The Baby Jupiter shown in the comic might be "born" in a similar manner.

:This is also reminiscent of the {{w|Doctor Who}} episode ''{{w|Kill the Moon}}'', in which it transpires that Earth's Moon is in fact a giant egg, and eventually hatches a space creature which, before flying away, lays a replacement egg/Moon in its place.

; No core; flat Earth conspiracists are wrong about Earth but right about Jupiter

: {{w|Modern flat Earth beliefs|Flat Earth}} is a debunked conspiracy theory that the Earth is not actually spherical, but flat, with some believing that world leaders are actively trying to hide this fact from the general public. This version of Jupiter proposes that while Earth may not be flat, Jupiter is, thereby not having a core at all.
: While we see the Flat Jupiter from an angle in this depiction, clearly for it to ''look'' spherical from Earth the disc of Jupiter (with 'fake phases' and even carefully adjusted shadows from the Jovian moons) must more or less face the Earth for most of the time. It is not known what arrangements were made to get the illusion past those images supposedly sent back from the various spacecraft that were passing by, or actually orbiting, Jupiter.

; {{w|Matryoshka doll}} (title text)

: Since Jupiter is by far the largest planet of the solar system (and in fact larger by both mass and volume than all other Solar System planets combined), it could hypothetically contain all other planets nested inside one another. The order from largest to smallest would be Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars and Mercury. Pluto could be included too, {{w|IAU definition of planet|if you are so inclined}}.

==Transcript==

:Current leading theories for what's in the center of Jupiter:

:[Variations of Jupiter. All except for the last are illustrated with a quartered 'solid segment' of the planet's 'atmosphere' removed to reveal the core.]

:[Jupiter with liquid material at its core]
:Diffuse mix of heavy elements and metallic hydrogen

:[Jupiter with a rocky core]
:Rocky core with metallic, hydrogen mantle

:[Jupiter with a pile of coins for a core, multiple dollar signs being shown]
:Valuable treasure

:[Jupiter with Earth for a core]
:Emergency backup Earth

:[Hollow Jupiter with a rocky planet in the middle, the outer layer held in place by inner supports]
:Regular planet pretending to be a gas giant to avoid attention

:[Jupiter with a smooth ball for a core]
:Hard ball from avocado

:[Jupiter with a small version of Jupiter for a core]
:Baby Jupiter, still gestating

:[Jupiter as a flat circle, with nothing chopped off]
:No core; flat Earth conspiracists are wrong about Earth but right about Jupiter

{{comic discussion}}<noinclude>

[[Category:Astronomy]]
[[Category:Food]]
[[Category:Conspiracy theory]]

2347: Dependency

2025-05-04T17:37:49Z

Nico31415926: Revert vandalism

{{comic
| number = 2347
| date = August 17, 2020
| title = Dependency
| image = dependency.png
| titletext = Someday ImageMagick will finally break for good and we'll have a long period of scrambling as we try to reassemble civilization from the rubble.
}}

==Explanation==
Technology architecture is often illustrated by a [https://www.guru99.com/images/1/102219_1135_TCPIPvsOSIM1.png stack diagram], in which higher levels of rectangles indicate components that are dependent on components in lower levels. This is analogous to a physical tower of blocks, in which higher blocks rest on lower blocks. The stack in this cartoon bears a striking resemblance to a physical block tower, suggesting the danger that the tower will lose its balance when a critical piece is removed, in this case a piece near the bottom, labeled as being maintained by a single semi-anonymous person located somewhere relatively unimportant doing it for their own unknown reasons without fame or acknowledgement. The concept of balance is not intended to be communicated by a stack diagram, making this a humorously absurd extension of a well-known diagram style.

===Background and Examples===
Taking code re-usability and modularization to its logical extreme has been a long-time tenet for programmers; programming began as a slow task on very memory-constrained systems, utilizing punch cards and days of delay waiting to discover a bug, so that reuse made things possible that otherwise wouldn't be. Once systems became small, fast, and able to hold a lot of data, the ability to provide higher and higher degrees of automation made reusable libraries a huge engine behind the development of technology. By outsourcing what would seem like basic functions, such as string manipulation, to other libraries, developers waste less time reinventing the wheel, so the philosophy goes (or as Beret Guy's business practices literally: [[2140: Reinvent the Wheel]]), and thus many tiny packages, many of which contained only one function, became popular dependencies. This was especially true in Unix and Linux, where an entire program is commonly used for one small task, and programs exist to tie others together into powerful shell scripts.
* {{w|Bash (Unix shell)|'''Bash shell'''}}
: The bash shell, which is used by virtually ''every'' Unix-like and Linux derivates and that is used by many system adminisitrators has been maintained since around 1993 by one person from Ohio, US for over 30 years as of 2025: Chet Ramey<ref>[https://tiswww.case.edu/php/chet/ Chet Ramey, Personal website (Last updated: Thu Sep 25 10:49:15 EDT 2014)]</ref><ref>[https://web.archive.org/web/20160811002459/http://www.computerworld.com.au/article/222764/ "The A-Z of Programming Languages: BASH/Bourne-Again Shell, (2008)" ]</ref>.
* {{w|'''ImageMagick'''}}
:ImageMagick, mentioned in the title text, is a popular, standalone utility released in 1990 that is used for performing transformations between various graphics file formats, and various other transformations. While there are also numerous libraries and APIs for performing these tasks within larger programs, ImageMagick is so popular and easy to use that many programs use its API or just find it easier to {{w|Shell (computing)#Other uses|shell out}} to ImageMagick to perform a necessary transformation. They therefore {{w|Dependency hell|depend}} on ImageMagick, and would break if ImageMagick were to disappear.
* {{w|'''OpenSSL'''}}: {{w|Heartbleed|Heartbleed bug}}
: In 2014, the Heartbleed revealed a significant portion of the internet was vulnerable to attack due to a bug in OpenSSL, a free and open-source library facilitating secure communication. One headline at the time demonstrated this comic in real life: [https://www.buzzfeed.com/chrisstokelwalker/the-internet-is-being-protected-by-two-guys-named-st "The Internet is Being Protected by Two Guys Named Steve"]. The aforementioned Steves were overworked, underfunded, and largely unknown volunteers whose efforts nevertheless underpinned the security of major websites throughout the world. Randall provided a concise, helpful explanation of the bug in [[1354: Heartbleed Explanation]].

* {{w|'''Core-js'''}}
: {{w|Node.js}} (a platform for JavaScript) and Python are two modern ecosystems providing huge stashes of centralized libraries where developers of the world can come together to stand on the shoulders of all the small useful libraries they make for each other, to make new ones that are more and more powerful, and also more and more prone to sudden new unexpected bugs somewhere in the dependency chain. JavaScript was designed to be an easy to use front end scripting language, not a basic and core backend language as users of node.js's {{w|npm (software)|NPM}} package manager have made it be. While in theory, such a system may sound good for developers who would need to write and maintain fewer lines of code, systems which are highly optimized are also highly susceptible to rapid changes. For example, the famous left-pad incident in the NPM package manager left many major and minor web services which depended on it unable to build. [https://www.theregister.com/2016/03/23/npm_left_pad_chaos/ A disgruntled developer unpublishing 11 lines of code was able to break everybody's build, because everyone was using it.]

: In 2020, the sole maintainer of the library [https://github.com/zloirock/core-js/blob/master/docs/2023-02-14-so-whats-next.md core-js], used by 75% of the top 100 websites to polyfill in new JavaScript features for old browsers and depended on by tons of popular libraries such as Babel, ran over two dark-clothed drunk pedestrians, one of whom was laying down, at night in Russia while speeding in front of a crossing. He had quit previous jobs to be able to maintain core-js, resulting in not having enough money to settle, and he was sentenced to 18 months in an open prison ([https://ru.wikipedia.org/wiki/%D0%9A%D0%BE%D0%BB%D0%BE%D0%BD%D0%B8%D1%8F-%D0%BF%D0%BE%D1%81%D0%B5%D0%BB%D0%B5%D0%BD%D0%B8%D0%B5 "колония-поселение"]).

* '''xz tool'''
: Leading up to 2024, a user account going by the name Jia Tan gained the trust of ''{{w|XZ Utils|xz}}'''s (one and only) maintainer. Over the course of 3 years, Jia Tan cleverly inserted a patch into ''xz'' that allows a remote user to gain root-level access via the common ssh protocol. This {{w|XZ_Utils_backdoor|compromised version of ''xz''}} was released in March 2024. Another programmer, Andres Freund, found this backdoor before ''xz'' was widely distributed.

The current model of libraries and open-source development (topics which Randall has addressed extensively in the past) relies heavily on the free and continued dedication of unpaid hobbyists. Though some major projects such as Linux may be able to garner enough attention to build an organization, many smaller projects, which are in turn reused by larger projects, may only be maintained by one person, either the founder or another who has taken the torch. Maintaining libraries requires both extensive knowledge of the library itself as well as any use cases and the broader community around it, which usually is suited for maintainers who have spent years at the task, and thus cannot be easily replaced. Thus, there are many abandoned projects on the internet as people move on to greener pastures. Far from the days of backwards compatibility, that's usually not a problem, unless a project happens to be far up the dependency chain, as illustrated, in which case there may be a crisis down the road for both the developers and the users down the chain.

==Transcript==
:[A tower of blocks is shown. The upper half consists of many tiny blocks balanced on top of one another to form smaller towers, labeled:]
:All modern digital infrastructure

:[The blocks rest on larger blocks lower down in the image, finally on a single large block. This is balanced on top of a set of blocks on the left, and on the right, a single tiny block placed on its side. This one is labeled:]
:A project some random person in Nebraska has been thanklessly maintaining since 2003

== References ==
<references/>
{{comic discussion}}
[[Category: Programming]]

2929: Good and Bad Ideas

2024-05-07T06:34:37Z

Nico31415926:

{{comic
| number = 2929
| date = May 6, 2024
| title = Good and Bad Ideas
| image = good_and_bad_ideas_2x.png
| imagesize = 595x522px
| noexpand = true
| titletext = While it seemed like a fun prank at the time, I realize my prank fire extinguishers full of leaded gasoline were a mistake.
}}

==Explanation==
{{incomplete|Created by a BLOOD FOR THE BLOOD GOD- Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This is a scatter plot comparing how good an idea sounds to how good the idea actually is. For example, leaded gasoline sounds like a good idea due to the anti-knocking effects, but is actually a bad idea due to lead toxicity. Fake prank fire extinguishers however sound bad and are bad as they can result in a dangerous situation in an emergency. Putting mold on infections sounds like a bad idea, but this could be referring to Penicillin, an antibiotic.

The title text combines leaded gasoline and a fake prank fire extinguisher into something that is worse than either. Not only is the fire extinguisher fake, it also releases flammable material onto the fire, and there is the additional lead toxicity.

{| class="wikitable"
|-
! Idea !! What it means !! How good it sounds !! How good it actually is !! Explanation
|-
|Leaded Gasoline||Adding tetraethyl lead to gasoline to increase performance||++||---||Lead is toxic. Burning the leaded gasoline in an engine releases the lead in the air. This is bad.
|-
|Bloodletting||Releasing "bad blood" from the veins||---||---||You need your blood.
|-
|Asbestos||Mineral which does not burn and is good isolation||+++||---||Asbestos was used extensively. Sadly the microscopic fibers which make up asbestos greatly increase the risk of cancer when inhaled.
|-
|Extension cords with prongs on both ends||||||||
|-
|Stair Kayaking||||||||
|-
|Fake prank fire extinguishers||||||||
|-
|Always saying what you think||||||||
|-
|Replying to spammers||||||||
|-
|Solar cars||||||||
|-
|Heelies||||||||
|-
|Prequels||||||||
|-
|Transition Lenses||||||||
|-
|Cutting pizza in squares||||||||
|-
|Project Orion||||||||
|-
|Combo washer dryers||||||||
|-
|Cutting sandwiches diagonally||||||||
|-
|Diverging diamond interchanges||||||||
|-
|Toasting sandwiches||||||||
|-
|Crumple zones||||||||
|-
|Sliced bread||||||||
|-
|Pizza||||||||
|-
|Eating citrus fruit while at sea||||0 (neutral)||+++||The vitamin C present in citrus fruits prevents one from contracting {{w|Scurvy|scurvy}}.
|-
|Putting mold on infections||||||||
|-
|Wheels on luggage||||||||
|-
|Heat pumps||||||||
|-
|Laser eye surgery||||||||
|-
|Fecal transplants||||||||
|-
|}
==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

Talk:2843: Professional Oaths

2023-10-24T06:11:25Z

Nico31415926:

added transcript [[User:Certified_nqh|Me]][[[285: Wikipedian Protester|''citation needed'']]][[Category:Pages using the "citation needed" template]] 05:47, 19 October 2023 (UTC)

every /^H.*ic$/ would be 4 syllables if it wasn't for hydroelectric [[User:Certified_nqh|Me]][[[285: Wikipedian Protester|''citation needed'']]][[Category:Pages using the "citation needed" template]] 05:55, 19 October 2023 (UTC)
:Maybe that should be "hydrœlectric", then! [[Special:Contributions/172.71.242.85|172.71.242.85]] 21:59, 19 October 2023 (UTC)

His-tor-ic[[Special:Contributions/162.158.146.77|162.158.146.77]]SomeoneElse1624

Clearly some lone editor had a grudge against hermeneutics, putting 'study' in scare quotes like that. AzureArmageddon 07:38, 19 October 2023 (UTC)

Hippopotamic Oath: First, lead your horse to water. [[Special:Contributions/172.70.86.139|172.70.86.139]] 08:02, 19 October 2023 (UTC)
:Cap doffed. Cap very much doffed. [[User:Yorkshire Pudding|Yorkshire Pudding]] ([[User talk:Yorkshire Pudding|talk]]) 20:16, 19 October 2023 (UTC)

Hypobolic Oath: Do your worst! [[Special:Contributions/172.70.250.73|172.70.250.73]] 09:55, 19 October 2023 (UTC)

Hypochondriac Oath: First, pretend to be sick! [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 13:05, 19 October 2023 (UTC)
:Nitpick: Hypochondriacs don't pretend to be sick, they believe they have an illness or are unduly worried about the possibility of having an illness. Someone who pretends to be sick is a malingerer. [[Special:Contributions/172.69.70.135|172.69.70.135]] 16:43, 19 October 2023 (UTC)
::Ok, fair :) So: Hypochondriac Oath: First, consult your doctor! [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 08:32, 20 October 2023 (UTC)

"A hippodrome is a circular arena" The classical Greek/Roman was not circular:
"One end of the ancient Greek hippodromos was semicircular, and the other end square with an extensive portico"
Maybe it would be more correct to talk about '''pairs''' of hypergolic substances?
[[User:Rps|Rps]] ([[User talk:Rps|talk]]) 12:19, 19 October 2023 (UTC)

I think the hyperbaric oath is probably referring to hyperbaric chambers, which are used in medical settings, such as treating scuba divers suffering from the bends. 14:08, 19 October 2023 (UTC)
:I wonder if the "holigraphic" one is directly inspired by [https://www.bbc.co.uk/news/business-67080941 this recent display]. (Although, by my reading, that's not ''really'' holographic, just an advanced form of stereographic display.) [[Special:Contributions/172.71.178.171|172.71.178.171]] 06:01, 20 October 2023 (UTC)

I missed the Hydroponic Oath (“first, maintain nutrient concentration”), the Hypocritic Oath (“first, judge others as you ''don't'' wish to be judged”), and the Hyperbolic Oath (“first, take two intersecting asymptotes”). [[Special:Contributions/108.162.221.60|108.162.221.60]] 15:34, 19 October 2023 (UTC)
:Isn't the Hypocritic Oath just "First, don't do this"?

I prefer the Hypocritical oath (insert political party of your choosing here). [[Special:Contributions/172.71.219.106|172.71.219.106]] 17:29, 19 October 2023 (UTC)
:All of them. [[explain_xkcd:Community_portal/Miscellaneous#Help_with_Creating_a_User_Page|Trogdor147]] ([[explain_xkcd:Community_portal/Miscellaneous#Help_with_Creating_a_User_Page|talk]]) 18:18, 19 October 2023 (UTC)

The Hypodermic Oath: "I've got you, under my skin..." [[User:Yorkshire Pudding|Yorkshire Pudding]] ([[User talk:Yorkshire Pudding|talk]]) 20:20, 19 October 2023 (UTC)

The Hypoglycemic Oath: "First, eat some sweets!" [[Special:Contributions/162.158.19.56|162.158.19.56]] 00:17, 20 October 2023 (UTC)

The Hypothetical Oath: "First, presume there is an oath." [[Special:Contributions/162.158.18.71|162.158.18.71]] 00:23, 20 October 2023 (UTC)

The Hieroglyphic Oath - “First, do no tomb-robbing.” [[User:Miamiclay|Miamiclay]] ([[User talk:Miamiclay|talk]]) 04:16, 20 October 2023 (UTC)

Hippy Oath: First, chill out, man! 
Hip-shaker Oath: First, do a shimmy. 
Hypotenuse Oath: First, find the squares of the other two sides. 
Hyperactive Oath: First, eat no sugar. 
[[Special:Contributions/172.70.91.236|172.70.91.236]] 10:36, 20 October 2023 (UTC)
::Hip-shaker Oath: First, do not lie.[[Special:Contributions/172.71.146.241|172.71.146.241]] 20:18, 23 October 2023 (UTC)

Hydrophobic Oath: First, repel water! 
Hydrophilic Oath: First, attract water! 
Hydrox Oath: First, enjoy a cookie! 
[[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]]) 14:24, 22 October 2023 (UTC)

Quite surprised that he didn't include a "Hypocritical Oath".
[[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 06:11, 24 October 2023 (UTC)

2343: Mathematical Symbol Fight

2023-05-10T16:31:14Z

Nico31415926:

{{comic
| number = 2343
| date = August 7, 2020
| title = Mathematical Symbol Fight
| image = mathematical_symbol_fight.png
| titletext = Oh no, a musician just burst in through the door confidently twirling a treble clef.
}}

==Explanation==
This comic imagines which {{w|List of mathematical symbols|mathematical symbols}} would be good in a fight if they were made corporeal in two (or three) dimensions.

Generally, objects with longer reach and pointier ends wound up on the right ("more useful") side of the scale, and symbols with less reach and more curves wound towards the left ("less useful") side. A straight line is farthest to the "more dangerous" side; however, the straight line does not appear to be any thicker or thinner, or pointier, than any of the other lines that would make it more "useful" (It should be noted that this chart seems to fall afoul of what {{w|Eliezer Yudkowsky}} (who also wrote HPMoR) calls the ''intent to kill'': that humans tend to define "winning a fight" and "useful" as causing some form of bodily harm on their opponent despite survival and purely defensive strategies being an equally valid goals.).

Below the chart, with the symbols listed in order of usefulness, eight characters wield eight of the symbols. See the [[#Table of symbols|table]] below for the meaning of each symbol.

The comic invokes {{w|Surreal humour|surreal humor}} by suggesting that mathematical symbols could be handled as physical objects in the real world. Another component of the humor is the implication that it is useful to prepare to use mathematical symbols in a fight, even though mathematicians, who use mathematical symbols, usually do not conduct their debates violently (though some stories suggest that {{w|Hippasus}} was killed by his fellow Pythagoreans for his proof that irrational numbers exist), and even if they did, they wouldn't use large reproductions of their symbols as weapons.

The title text refers to a {{w|Treble clef}}, which is not a mathematical symbol but rather a {{w|List of musical symbols|musical symbol}}. The note of concern in the text suggests musical symbols may be viewed in such fights as exotic or especially dangerous. See also the last entry in the table below.

==Table of symbols==
{| class="wikitable"
! Symbol
! Meaning
! Notes on using in a fight
|-
| ℝ
|The set of [[wikipedia:real number|real number]]s
|[[Megan]] seems to be struggling with a giant version of this symbol because of its weight. A very strong person might find it slightly more useful as a bludgeon.
|-
| θ
|[[wikipedia:Theta#Mathematics_and_science|Theta]]
|This symbol is not very sharp, and [[White Hat]] is unable to use it in combat. It would not work as a good shield due to the hole in the symbol, but it possibly could be thrown. (The later version of Xena's chakram had a bar in the middle.)
|-
| ∅
|[[wikipedia:Empty set|Empty set]]
|Similarly shaped to theta, but identified as being slightly more useful, presumably because the parts of the bar that extend beyond the circle can be used as thrusting weapons. Alternatively, the round nature of the symbol makes it easier to handle for defense, by holding on to the line and using the edge of the circular part to block.
|-
| ∞
|infinity
|Could be gripped between the rings and used as a blunt instrument.
|-
| >
|Greater than
|Could be used to thrust with the point, but lacks a grip by which to do so. If held by one leg, the angle and balance is wrong to use it as a pick. Could also be used as a [[wikipedia:Boomerang|boomerang]].
|-
| ∝
|[[wikipedia:Proportionality_(mathematics)#Direct_proportionality|Direct Proportionality]] (not to be confused with lowercase {{w|Alpha#Mathematics and science|alpha}})
|Could be brandished by the ring and used to thrust with the prongs, but the two prongs extending at 90-degree angles make thrusting motions awkward.
|-
| ∪
|{{w|union (set theory)}}
|Could be used as a boomerang, which is {{tvtropes|PrecisionGuidedBoomerang|notoriously less practical in real life than in fiction}}
|-
| ∈/ϵ
|{{w|Element (mathematics)|member of}} (set theory) or the "lunate" lowercase {{w|Epsilon#Symbol|epsilon}}
|[[Cueball]] is holding this in the manner of a Klingon "{{w|Bat'leth}}" from the ''Star Trek'' franchise. The Bat'leth is [https://youtu.be/VsElSDXPgSA infamous] among swordfighters for being rather impractical, and that the Klingon warrior race would have been better suited using swords like humans. It seems Randall agrees, as the ∈ is quite far on the left of the chart.
|-
| π
|[[wikipedia:Pi|pi]]
|Could be used as a hammer, but the two handles would make doing so impractical.
|-
| ∀
|"{{w|Universal quantification|for all}}"
|Could be held by the crossbar clenched in a fist, and then used as a {{w|push dagger}}, with the legs acting as a guard. Or could be held by the legs.
Compared to the similar Δ (delta) the point is sharper, the grip is closer to the point so it would be easier to control (keep the weapon from twisting). It is unclear why it is listed as much less effective than the delta. Perhaps the guard legs are too long?
|-
| ∂
|{{w|∂}} ([[wikipedia:Partial derivative|partial derivative]] or [[wikipedia:Boundary_(topology)|boundary operator]])
|It's not clear why Randall ranks this symbol as so much less effective than the similarly-shaped 𝜌, but the curl in the "tail" of the ∂ would give it a shorter lever arm when swung and would disrupt the balance.
|-
| +
|[[wikipedia:Plus_and_minus_signs#Plus_sign|Plus]]
|Maybe thrown like a {{w|shuriken}}? It could also be used like [[wikipedia:Kylo Ren|Kylo Ren]]'s lightsaber.
|-
| Ψ
|[[wikipedia:Psi#Mathematics|Psi]]
|It could be used as a slightly-less-functional trident or pitchfork, with a shorter handle. More particularly, it resembles a {{w|Sai (weapon)|sai}} (which, funnily enough, is how "Psi" is pronounced).
|-
| ≠
|not equal sign
|Could be gripped by the crossbar, using the lengths to puncture. Notably, the equal sign (=) is absent from the chart, likely because the lengths are separate and would not be used as a single entity.
|-
| ~
|[[wikipedia:Tilde#Mathematics|tilde]], meaning "approximately", equivalent, or several transforms of a function. Sometimes also used to symbolize logical NOT.
|A potentially dangerous throwing weapon. Could also be similar to a wavy bladed dagger ({{w|Kris}}) or a sword ({{w|Flame-bladed sword}}).
|-
| #
|[[wikipedia:Cardinality|Cardinality]], [[wikipedia:Connected_sum|connected sum]] (knot theory), or [[wikipedia:Primorial|primorial]].
|[[Blondie]] uses this symbol, gripping it by two of the prongs on one side. The other three prongs could thus be swung at opponents, but being sharp on all sides would pose a threat to the user as well as the opponent.
|-
| Δ
|[[wikipedia:Delta_(letter)|Delta]]
|Could be held with one bar clenched in a fist, and then used as a {{w|push dagger}}. It is unclear why listed as much more effective than ∀. Also, delta could be thrown like a star.
|-
| ⇒
|[[wikipedia:Material_conditional|Material consequence]] or [[wikipedia:Logical_consequence|Logical consequence]], meaning "implies"
|The point is nice, but having two poles (or one board-like thick handle, if the shape is drawn "closed" at the back) would be difficult to wield. A collection of them might make a nice defensive pike line.
|-
| ⋅
|decimal point (or multiplication sign)
|Functionally a ball, and could therefore be thrown as a projectile weapon, or scattered on the ground as a trip hazard.
|-
| ζ
|{{w|Zeta#Mathematics_and_science|Zeta}}
|Could be sharpened into a scythe or curved saber, depending on the curvature and length of the 'tail' at the bottom.
|-
| ℵ
|[[wikipedia:Aleph_number|Aleph number]]
|The irregular shape of the symbol leads to edges and points on all sides; thus it could be brandished or thrown in the manner of a shuriken.
|-
| Γ
|uppercase Greek letter {{w|Gamma#Uppercase|Gamma}}
|If this letter is formed with {{w|serif}}s, it could be used as an axe or hook, and if it is made {{w|sans-serif}}, it would make a powerful pick or war hammer.
|-
| √
|{{w|Radical symbol}}
|Randall has drawn this sign with a long overbar, which makes it useful like a {{w|Pole weapon|pole arm}}. [[Black Hat]] has chosen this symbol in his fight against [[Hairy]].
|-
| ''ρ''
|{{w|Prime_constant|italic rho}}
|[[Ponytail]] is brandishing this symbol against [[Danish]], apparently using it like a club or hammer and striking with the curve.
|-
| ∮
|{{w|contour integral}}
|This symbol is drawn with a very tight center, giving it an almost identical figure to the regular integral symbol. Presumably, the added bulk for marginal additional use earns it a rating of 'less effective'.
|-
| ∫
|{{w|integral}}
|Could be used in the manner of a shepherd's crook, or as a {{w|Bill (weapon)|billhook}}. Could be used as a {{w|spear thrower}}, combined with ⋅ or ⇀.
|-
| →
|Implies; X→Y means that if X is true, then Y is also true
|[[Danish]] is brandishing this symbol against Ponytail, apparently using it like a spear.
|-
| ⊥
|{{w|up tack}} or falsum, indicating a false proposition in logic, perpendicular lines in geometry, or the bottom element in a partial order
|Used as a {{w|war hammer}} (held by the long stem), the opponent would be struck with either leg of the top of the T. Held by the short legs (like a wishbone), could be used as a two handed sword.
(If tipped with a knapped stone head, it could become a {{w|Folsom point|falsum point}}.)
|-
| ⇀
|{{w|Vector notation}}
|Could be used as a single-barbed spear or, if held by the other end, similarly to a sabre. The multi-functionality is probably why it is listed as more useful than the 'implies' arrow.
|-
| ––
|{{w|Fraction#Vocabulary|Fraction bar}} (division) or {{w|Overline#Math_and_science|overline}} (complex conjugate or mean) or {{w|Plus and minus signs#Minus sign|minus sign}}.
|[[Hairy]] is brandishing this symbol against Black Hat. The single shaft would allow it to be used in the manner of a {{w|quarterstaff}}, {{w|bō}}, or other {{w|stick-fighting}} weapon. Of the symbols shown in the comic, Randall considers this one the most useful in a fight, presumably because of its greater reach than the vector arrow and its simplicity compared to the radix root symbol. Alternatively, could be handled like a pike, with a reach greater than that of an implication or vector arrow.
|-
| 𝄞
|{{w|Treble clef}} (title text)
|Mentioned in the title text; this is not a mathematical symbol, but a musical symbol. The treble clef is a much more complicated symbol than those used in mathematics, hence the musician's "confidence" in his weapon. The curve at the bottom could be used as a hook, the upper curl could be used as a blunt weapon, and the tight curl of the center would serve as a better defensive shield than theta.
|}

==Transcript==
:[A chart is shown with 30 different symbols arranged above a line with arrows in both ends and with 17 ticks between the arrow heads. The symbols are mostly in two rows, but the first two symbols from the left do not have another symbol above them, and towards the right there are a segment with three rows of symbols. Above the symbols there is a heading and a subheading. And beneath those there is a long arrow pointing right with a label above it.]
:<big>Mathematical Symbols</big>
:By how useful they would be in a fight
:More useful
: ℝ ∅ > ∝ π + Ψ ~ ⇒ ⋅ Γ √ ∮ ∫ ⇀
: θ ∞ ∪ ∈ ∀ ∂ ≠ # Δ ζ ℵ ''ρ'' → ⊥ ––

:[Below the double arrow line are eight characters that fight each other in groups of two by using some of the symbols shown above them as weapons. They have chosen symbols that are almost above them in the chart.]
:[Megan is awkwardly handling a giant "ℝ" holding it up against White Hat who is holding a "θ" (or "∅"?) with both hands, as a shield.]
:[Cueball is holding an "∈" in both hands, with its "tines" pointed towards Blondie, who is swatting at him with a "#".]
:[Ponytail is leaping at Danish, swinging a "''ρ''" like an axe, while Danish is leaning back and thrusting a "→" back at her.]
:[Black Hat is swinging a long "√" like a polearm at Hairy, who is holding a long "⎯" defensively.]

==Trivia==
*Here is a list of symbols from left to right (by rightmost edge):
** ℝ θ ∅ ∞ > ∪ ∝ ∈ ∀ π ∂ + ≠ Ψ # ~ △ ζ ⇒ ⋅ ℵ Γ ''ρ'' √ → ∮ ∫ ⊥ ⇀ ––
**Note: Where two symbols had similar right-most edges, the overlay grid on an ASUS pro-art display was used to decide which one went further right.

{{comic discussion}}

[[Category:Charts]]
[[Category:Rankings]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Blondie]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Danish]]
[[Category:Comics featuring Black Hat]]
[[Category:Comics featuring Hairy]]
[[Category:Math]]
[[Category:Music]]

Talk:2710: Hydropower Breakthrough

2022-12-14T06:04:50Z

Nico31415926:

ChatGPT sez:
:The comic depicts Beret Guy, a character known for his expertise in science and engineering, standing on a podium and announcing that their hydroelectric dam has achieved a level of efficiency greater than one, producing more water than was fed into it. This is cause for celebration, as it indicates that the dam is functioning properly and efficiently. However, the second off-panel voice raises a question, suggesting that there may be more to the situation than initially thought.
:The title text adds further information by revealing that a hydroelectric dam is also known as a heavy water reactor. This suggests that the dam may not be operating in the traditional way, but rather may be using a different type of technology, such as nuclear power, to produce the excess water. This could raise concerns about safety and the potential risks associated with this type of technology.
Meh. [[Special:Contributions/172.69.33.45|172.69.33.45]] 03:44, 13 December 2022 (UTC)

It *is* possible. All Beret Guy has to do is use the electricity to run air conditioners, which will have one side condensing water from the atmosphere, ergo more water coming out than went in. [[User:SDSpivey|SDSpivey]] ([[User talk:SDSpivey|talk]]) 04:00, 13 December 2022 (UTC)
:I think there's a conservation of energy violation here, but can't model the entire system. [[Special:Contributions/172.70.134.97|172.70.134.97]] 14:31, 13 December 2022 (UTC)

Considering that he phrases it "more water than we fed into it" in the past tense, it might just be that there's a leak in the dam.
[[Special:Contributions/172.69.33.19|172.69.33.19]] 04:06, 13 December 2022 (UTC) mraction

More variation: "more water than *we* fed into it" ie not counting water from the river that feeds it, or rainfall. There's also the title text turn of phrase "heavy water reactor". "heavy" could refer to either the "water" (in the sense of gravity, or deuterium passing through), or the "reactor" (as in its mass) - [[Special:Contributions/172.70.210.242|172.70.210.242]] 05:43, 13 December 2022 (UTC)

If Q is only barely >1 it could square the circle by converting atoms to oxygen by fusion in order to create water but the whole energy of the dam is used to make the fusion of a few oxygen atoms.

"Another member of audience, who is presumably familiar with regular physics, says "Wait.", because conservation of mass usually applies to water such that a dam should produce the same amount of water as that fed into it. That said, for a regular dam in a natural valley like the one shown in this comic, it is entirely normal for the dam to "produce" more water than input in the sense that in addition to water from upstream rivers, the dam will also output any "unofficial" inflow from direct rainfall above and from uncharted sources of groundwater below." 
I thought that the "Wait" comment was in relation to the fact that the announcement, although achieving something that was not achieved so far, is impractical. As the power plants are expected to produce energy, announcement that they produce additional water is irrelevant, and the "wait" comment indicated that they have missed the point. {{unsigned ip|172.68.50.204}}

Given the title of ''Hydropower Breakthrough'', is a possible interpretation that the dam is just about to fail? --[[Special:Contributions/172.68.110.171|172.68.110.171]] 10:35, 13 December 2022 (UTC)

My immediate thought was that he was using the generated electricity to ignite a hydrogen cell, but my immediate thoughts are always weird. [[Special:Contributions/172.70.134.97|172.70.134.97]] 14:31, 13 December 2022 (UTC)

I feel Randall's comic is strongly indicative of a fair degree of skepticism around recent fusion power hype (many existing ''fission'' reactors produce an energy surplus, but fail to meet their cost of operations)... Yet, the comic's explanation currently reads as a guileless exhortation of fusion's possibilities, making no mention of the many other challenges faced by fusion reactors, besides this critical ''first step'' of generating more power than required to sustain the reaction. The comic is clearly making light of the recent publication\marketing push, yet the explanation gives no sign that fusion power is anything but practical & just around the corner. Fusion still has many remaining challenges to overcome, before reaching practicality as an energy source even for military applications (moreso still, for public utility); wind & solar are the top KWh:$ producers & another 10 or 100 billion spent researching fusion are very unlikely to change that in the next couple decades. In fact, solar research returns more Watts per dollar. The comic should probably mention the other challenges involved in nuclear fusion power, besides raw output quantity?
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 16:00, 13 December 2022 (UTC)
:Top KWh:$ producers sure, by which statistics? The effectivity of different kinds of power plants varies widely both with specific location, cost of input and the method used, but usually the hydroelectric damns build in good terrain would take a lead, especially considering that they can work for more than century. Which wind or solar power plant can hope for that? There is sure lot of research still necessary to make fusion power plants reality, but long term it can easily pay itself, and it can work anywhere, while damns need to be build on river, wind onshore (offshore are MUCH less effective and no research will change that) and solar, well, not too far from equator and somewhere with sunny weather, it wouldn't work when raining. Or, well, in space. Fission might also get good value from research if the research actually will be happening. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:21, 13 December 2022 (UTC)

I think the explanation is overthinking it. The joke is that there's a leak in the dam.
[[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 16:37, 13 December 2022 (UTC)
:You mean you only see one of the long list of jokes in this comic? -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:21, 13 December 2022 (UTC)
:: I guess my mind just thought of the simplest joke first? :shrug: -- [[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 06:03, 14 December 2022 (UTC)

The explanation says nothing about the effect this would have downriver from the dam. [[User:Inquirer|Inquirer]] ([[User talk:Inquirer|talk]]) 16:51, 13 December 2022 (UTC)

I wonder if the image depicts Vajont Dam, https://en.wikipedia.org/wiki/Vajont_Dam, which was overtopped by a massive wave generated by a landslide--briefly outputting MUCH more water than was input. [[Special:Contributions/172.71.150.3|172.71.150.3]] 18:38, 13 December 2022 (UTC)

Is not counting rain, equivalent to only counting the energy released by the laswers, not the energy fed into the lasers? [[User:Arachrah|Arachrah]] ([[User talk:Arachrah|talk]]) 20:47, 13 December 2022 (UTC)

Another possible reason for the "Wait." comment is that, if Beret Guy's dam is indeed magically creating water, then left unchecked it could, over time, lead to the sea levels rising higher than all land surface on Earth. This would indeed be a very unfortunate situation. [[User:Dansiman|Dansiman]] ([[User talk:Dansiman|talk]]) 22:24, 13 December 2022 (UTC)

One of the things I just edited out was the claim that discharging (effectively) distilled water could dehydrate the environment. With an unnaturally hypertonic (dilute) water-source, creatures would not dry out but (if anything) ''absorb'' more water under osmotic pressure, which could lead to cells bursting from too much effort to balance things out. Hypotonic water (too many salts, for a given organism) would draw cellular/bodily stores of water out. Probably a 'pure water discharge' of the kind described would locally dilute the natural body of water that it was set to run into, but would also fairly quickly make itself/its dump-body more eager than normal to adopt ions from the immediate geologies of the run-off path. If you don't presume deluging a parched land with basically your fancy new-water output, there might be effects upon plants and animals adapted to more hard and/or briney water-environments (e.g. creating a disruptive freshwater lagoon within a saltwater marsh), with some ecological concerns to be addressed by careful use of mixing ponds (almost the opposite of most waste-water outlettings, which may require settling ponds or filtrating reed-beds) and questions about relative temperatures (which can be useful ''or'' disruptive to the survival of local creatures who might previously have migrated to more naturally warmer expanses of water), but overall it'd be better than most post-industrial water outflows. With the right eco-oversight to spot side-effects. [[Special:Contributions/172.71.242.74|172.71.242.74]] 01:39, 14 December 2022 (UTC)

Talk:2710: Hydropower Breakthrough

2022-12-14T06:04:25Z

Nico31415926:

ChatGPT sez:
:The comic depicts Beret Guy, a character known for his expertise in science and engineering, standing on a podium and announcing that their hydroelectric dam has achieved a level of efficiency greater than one, producing more water than was fed into it. This is cause for celebration, as it indicates that the dam is functioning properly and efficiently. However, the second off-panel voice raises a question, suggesting that there may be more to the situation than initially thought.
:The title text adds further information by revealing that a hydroelectric dam is also known as a heavy water reactor. This suggests that the dam may not be operating in the traditional way, but rather may be using a different type of technology, such as nuclear power, to produce the excess water. This could raise concerns about safety and the potential risks associated with this type of technology.
Meh. [[Special:Contributions/172.69.33.45|172.69.33.45]] 03:44, 13 December 2022 (UTC)

It *is* possible. All Beret Guy has to do is use the electricity to run air conditioners, which will have one side condensing water from the atmosphere, ergo more water coming out than went in. [[User:SDSpivey|SDSpivey]] ([[User talk:SDSpivey|talk]]) 04:00, 13 December 2022 (UTC)
:I think there's a conservation of energy violation here, but can't model the entire system. [[Special:Contributions/172.70.134.97|172.70.134.97]] 14:31, 13 December 2022 (UTC)

Considering that he phrases it "more water than we fed into it" in the past tense, it might just be that there's a leak in the dam.
[[Special:Contributions/172.69.33.19|172.69.33.19]] 04:06, 13 December 2022 (UTC) mraction

More variation: "more water than *we* fed into it" ie not counting water from the river that feeds it, or rainfall. There's also the title text turn of phrase "heavy water reactor". "heavy" could refer to either the "water" (in the sense of gravity, or deuterium passing through), or the "reactor" (as in its mass) - [[Special:Contributions/172.70.210.242|172.70.210.242]] 05:43, 13 December 2022 (UTC)

If Q is only barely >1 it could square the circle by converting atoms to oxygen by fusion in order to create water but the whole energy of the dam is used to make the fusion of a few oxygen atoms.

"Another member of audience, who is presumably familiar with regular physics, says "Wait.", because conservation of mass usually applies to water such that a dam should produce the same amount of water as that fed into it. That said, for a regular dam in a natural valley like the one shown in this comic, it is entirely normal for the dam to "produce" more water than input in the sense that in addition to water from upstream rivers, the dam will also output any "unofficial" inflow from direct rainfall above and from uncharted sources of groundwater below." 
I thought that the "Wait" comment was in relation to the fact that the announcement, although achieving something that was not achieved so far, is impractical. As the power plants are expected to produce energy, announcement that they produce additional water is irrelevant, and the "wait" comment indicated that they have missed the point. {{unsigned ip|172.68.50.204}}

Given the title of ''Hydropower Breakthrough'', is a possible interpretation that the dam is just about to fail? --[[Special:Contributions/172.68.110.171|172.68.110.171]] 10:35, 13 December 2022 (UTC)

My immediate thought was that he was using the generated electricity to ignite a hydrogen cell, but my immediate thoughts are always weird. [[Special:Contributions/172.70.134.97|172.70.134.97]] 14:31, 13 December 2022 (UTC)

I feel Randall's comic is strongly indicative of a fair degree of skepticism around recent fusion power hype (many existing ''fission'' reactors produce an energy surplus, but fail to meet their cost of operations)... Yet, the comic's explanation currently reads as a guileless exhortation of fusion's possibilities, making no mention of the many other challenges faced by fusion reactors, besides this critical ''first step'' of generating more power than required to sustain the reaction. The comic is clearly making light of the recent publication\marketing push, yet the explanation gives no sign that fusion power is anything but practical & just around the corner. Fusion still has many remaining challenges to overcome, before reaching practicality as an energy source even for military applications (moreso still, for public utility); wind & solar are the top KWh:$ producers & another 10 or 100 billion spent researching fusion are very unlikely to change that in the next couple decades. In fact, solar research returns more Watts per dollar. The comic should probably mention the other challenges involved in nuclear fusion power, besides raw output quantity?
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 16:00, 13 December 2022 (UTC)
:Top KWh:$ producers sure, by which statistics? The effectivity of different kinds of power plants varies widely both with specific location, cost of input and the method used, but usually the hydroelectric damns build in good terrain would take a lead, especially considering that they can work for more than century. Which wind or solar power plant can hope for that? There is sure lot of research still necessary to make fusion power plants reality, but long term it can easily pay itself, and it can work anywhere, while damns need to be build on river, wind onshore (offshore are MUCH less effective and no research will change that) and solar, well, not too far from equator and somewhere with sunny weather, it wouldn't work when raining. Or, well, in space. Fission might also get good value from research if the research actually will be happening. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:21, 13 December 2022 (UTC)

I think the explanation is overthinking it. The joke is that there's a leak in the dam.
[[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 16:37, 13 December 2022 (UTC)
:You mean you only see one of the long list of jokes in this comic? -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:21, 13 December 2022 (UTC)
:: I guess my mind just thought of the simpler joke first? :shrug:
[[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 06:03, 14 December 2022 (UTC)

The explanation says nothing about the effect this would have downriver from the dam. [[User:Inquirer|Inquirer]] ([[User talk:Inquirer|talk]]) 16:51, 13 December 2022 (UTC)

I wonder if the image depicts Vajont Dam, https://en.wikipedia.org/wiki/Vajont_Dam, which was overtopped by a massive wave generated by a landslide--briefly outputting MUCH more water than was input. [[Special:Contributions/172.71.150.3|172.71.150.3]] 18:38, 13 December 2022 (UTC)

Is not counting rain, equivalent to only counting the energy released by the laswers, not the energy fed into the lasers? [[User:Arachrah|Arachrah]] ([[User talk:Arachrah|talk]]) 20:47, 13 December 2022 (UTC)

Another possible reason for the "Wait." comment is that, if Beret Guy's dam is indeed magically creating water, then left unchecked it could, over time, lead to the sea levels rising higher than all land surface on Earth. This would indeed be a very unfortunate situation. [[User:Dansiman|Dansiman]] ([[User talk:Dansiman|talk]]) 22:24, 13 December 2022 (UTC)

One of the things I just edited out was the claim that discharging (effectively) distilled water could dehydrate the environment. With an unnaturally hypertonic (dilute) water-source, creatures would not dry out but (if anything) ''absorb'' more water under osmotic pressure, which could lead to cells bursting from too much effort to balance things out. Hypotonic water (too many salts, for a given organism) would draw cellular/bodily stores of water out. Probably a 'pure water discharge' of the kind described would locally dilute the natural body of water that it was set to run into, but would also fairly quickly make itself/its dump-body more eager than normal to adopt ions from the immediate geologies of the run-off path. If you don't presume deluging a parched land with basically your fancy new-water output, there might be effects upon plants and animals adapted to more hard and/or briney water-environments (e.g. creating a disruptive freshwater lagoon within a saltwater marsh), with some ecological concerns to be addressed by careful use of mixing ponds (almost the opposite of most waste-water outlettings, which may require settling ponds or filtrating reed-beds) and questions about relative temperatures (which can be useful ''or'' disruptive to the survival of local creatures who might previously have migrated to more naturally warmer expanses of water), but overall it'd be better than most post-industrial water outflows. With the right eco-oversight to spot side-effects. [[Special:Contributions/172.71.242.74|172.71.242.74]] 01:39, 14 December 2022 (UTC)

Talk:2710: Hydropower Breakthrough

2022-12-14T06:03:54Z

Nico31415926:

ChatGPT sez:
:The comic depicts Beret Guy, a character known for his expertise in science and engineering, standing on a podium and announcing that their hydroelectric dam has achieved a level of efficiency greater than one, producing more water than was fed into it. This is cause for celebration, as it indicates that the dam is functioning properly and efficiently. However, the second off-panel voice raises a question, suggesting that there may be more to the situation than initially thought.
:The title text adds further information by revealing that a hydroelectric dam is also known as a heavy water reactor. This suggests that the dam may not be operating in the traditional way, but rather may be using a different type of technology, such as nuclear power, to produce the excess water. This could raise concerns about safety and the potential risks associated with this type of technology.
Meh. [[Special:Contributions/172.69.33.45|172.69.33.45]] 03:44, 13 December 2022 (UTC)

It *is* possible. All Beret Guy has to do is use the electricity to run air conditioners, which will have one side condensing water from the atmosphere, ergo more water coming out than went in. [[User:SDSpivey|SDSpivey]] ([[User talk:SDSpivey|talk]]) 04:00, 13 December 2022 (UTC)
:I think there's a conservation of energy violation here, but can't model the entire system. [[Special:Contributions/172.70.134.97|172.70.134.97]] 14:31, 13 December 2022 (UTC)

Considering that he phrases it "more water than we fed into it" in the past tense, it might just be that there's a leak in the dam.
[[Special:Contributions/172.69.33.19|172.69.33.19]] 04:06, 13 December 2022 (UTC) mraction

More variation: "more water than *we* fed into it" ie not counting water from the river that feeds it, or rainfall. There's also the title text turn of phrase "heavy water reactor". "heavy" could refer to either the "water" (in the sense of gravity, or deuterium passing through), or the "reactor" (as in its mass) - [[Special:Contributions/172.70.210.242|172.70.210.242]] 05:43, 13 December 2022 (UTC)

If Q is only barely >1 it could square the circle by converting atoms to oxygen by fusion in order to create water but the whole energy of the dam is used to make the fusion of a few oxygen atoms.

"Another member of audience, who is presumably familiar with regular physics, says "Wait.", because conservation of mass usually applies to water such that a dam should produce the same amount of water as that fed into it. That said, for a regular dam in a natural valley like the one shown in this comic, it is entirely normal for the dam to "produce" more water than input in the sense that in addition to water from upstream rivers, the dam will also output any "unofficial" inflow from direct rainfall above and from uncharted sources of groundwater below." 
I thought that the "Wait" comment was in relation to the fact that the announcement, although achieving something that was not achieved so far, is impractical. As the power plants are expected to produce energy, announcement that they produce additional water is irrelevant, and the "wait" comment indicated that they have missed the point. {{unsigned ip|172.68.50.204}}

Given the title of ''Hydropower Breakthrough'', is a possible interpretation that the dam is just about to fail? --[[Special:Contributions/172.68.110.171|172.68.110.171]] 10:35, 13 December 2022 (UTC)

My immediate thought was that he was using the generated electricity to ignite a hydrogen cell, but my immediate thoughts are always weird. [[Special:Contributions/172.70.134.97|172.70.134.97]] 14:31, 13 December 2022 (UTC)

I feel Randall's comic is strongly indicative of a fair degree of skepticism around recent fusion power hype (many existing ''fission'' reactors produce an energy surplus, but fail to meet their cost of operations)... Yet, the comic's explanation currently reads as a guileless exhortation of fusion's possibilities, making no mention of the many other challenges faced by fusion reactors, besides this critical ''first step'' of generating more power than required to sustain the reaction. The comic is clearly making light of the recent publication\marketing push, yet the explanation gives no sign that fusion power is anything but practical & just around the corner. Fusion still has many remaining challenges to overcome, before reaching practicality as an energy source even for military applications (moreso still, for public utility); wind & solar are the top KWh:$ producers & another 10 or 100 billion spent researching fusion are very unlikely to change that in the next couple decades. In fact, solar research returns more Watts per dollar. The comic should probably mention the other challenges involved in nuclear fusion power, besides raw output quantity?
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 16:00, 13 December 2022 (UTC)
:Top KWh:$ producers sure, by which statistics? The effectivity of different kinds of power plants varies widely both with specific location, cost of input and the method used, but usually the hydroelectric damns build in good terrain would take a lead, especially considering that they can work for more than century. Which wind or solar power plant can hope for that? There is sure lot of research still necessary to make fusion power plants reality, but long term it can easily pay itself, and it can work anywhere, while damns need to be build on river, wind onshore (offshore are MUCH less effective and no research will change that) and solar, well, not too far from equator and somewhere with sunny weather, it wouldn't work when raining. Or, well, in space. Fission might also get good value from research if the research actually will be happening. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:21, 13 December 2022 (UTC)

I think the explanation is overthinking it. The joke is that there's a leak in the dam.
[[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 16:37, 13 December 2022 (UTC)
:You mean you only see one of the long list of jokes in this comic? -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:21, 13 December 2022 (UTC)
I guess my mind just thought of the simpler joke first? :shrug:
[[User:Nico31415926|An idiot]] ([[User talk:Nico31415926|talk]]) 06:03, 14 December 2022 (UTC)

The explanation says nothing about the effect this would have downriver from the dam. [[User:Inquirer|Inquirer]] ([[User talk:Inquirer|talk]]) 16:51, 13 December 2022 (UTC)

I wonder if the image depicts Vajont Dam, https://en.wikipedia.org/wiki/Vajont_Dam, which was overtopped by a massive wave generated by a landslide--briefly outputting MUCH more water than was input. [[Special:Contributions/172.71.150.3|172.71.150.3]] 18:38, 13 December 2022 (UTC)

Is not counting rain, equivalent to only counting the energy released by the laswers, not the energy fed into the lasers? [[User:Arachrah|Arachrah]] ([[User talk:Arachrah|talk]]) 20:47, 13 December 2022 (UTC)

Another possible reason for the "Wait." comment is that, if Beret Guy's dam is indeed magically creating water, then left unchecked it could, over time, lead to the sea levels rising higher than all land surface on Earth. This would indeed be a very unfortunate situation. [[User:Dansiman|Dansiman]] ([[User talk:Dansiman|talk]]) 22:24, 13 December 2022 (UTC)

One of the things I just edited out was the claim that discharging (effectively) distilled water could dehydrate the environment. With an unnaturally hypertonic (dilute) water-source, creatures would not dry out but (if anything) ''absorb'' more water under osmotic pressure, which could lead to cells bursting from too much effort to balance things out. Hypotonic water (too many salts, for a given organism) would draw cellular/bodily stores of water out. Probably a 'pure water discharge' of the kind described would locally dilute the natural body of water that it was set to run into, but would also fairly quickly make itself/its dump-body more eager than normal to adopt ions from the immediate geologies of the run-off path. If you don't presume deluging a parched land with basically your fancy new-water output, there might be effects upon plants and animals adapted to more hard and/or briney water-environments (e.g. creating a disruptive freshwater lagoon within a saltwater marsh), with some ecological concerns to be addressed by careful use of mixing ponds (almost the opposite of most waste-water outlettings, which may require settling ponds or filtrating reed-beds) and questions about relative temperatures (which can be useful ''or'' disruptive to the survival of local creatures who might previously have migrated to more naturally warmer expanses of water), but overall it'd be better than most post-industrial water outflows. With the right eco-oversight to spot side-effects. [[Special:Contributions/172.71.242.74|172.71.242.74]] 01:39, 14 December 2022 (UTC)

Talk:2710: Hydropower Breakthrough

2022-12-13T16:37:06Z

Nico31415926:

985: Percentage Points

2022-10-11T05:56:35Z

Nico31415926:

{{comic
| number = 985
| date = December 2, 2011
| title = Percentage Points
| image = percentage_points.png
| titletext = Grayton also proposed making college scholarships available exclusively to sexually active teens, amnesty for illegal immigrants who create room for themselves by killing a citizen, and a graduated income tax based on penis size. He has been endorsed by Tracy Morgan, John Wilkes Booth's ghost, and the Time Cube guy.
}}

==Explanation==
Senator Grayton is a fictional character, made up for this comic; which is unusual for xkcd, as it typically uses real-world references.

The issues that Grayton supports:

*Tax Breaks to Drunk Drivers: Grayton proposes giving those who have been convicted of a {{w|DUI}} or DWI (i.e. Driving Under the Influence or Driving While Intoxicated) money back on their taxes, when those infractions are typically severely penalized, as drunk driving has resulted in numerous deaths.
*{{w|Predator Drones}} and the {{w|Christmas controversy|War on Christmas}}: The War on {{w|Christmas}} is not a real war; it is simply the perception by some {{w|Christian}}s that non-Christians are trying to replace traditional Christmas imagery with more inclusive and generic holiday customs. No politicians have explicitly announced their support of the "War on Christmas," and the idea that one would not only do so, but would also want to use drones—ostensibly to harm or possibly kill people—in the effort is an absurd exaggeration of a relatively harmless culture war.

The term {{w|percentage point}} is used to overcome an ambiguity when comparing two percentages.

'''Reduction of a stated number by a percentage'''
:When the original value is given as a number, there is no ambiguity. In the statement below the only possible conclusion is that now only 162,000 people approve of Grayton.
:''Previously 200,000 people approved of Senator Grayton, and then his approval rating dropped by 19%.''

'''Reduction of a percentage by a percentage'''
:When the original approval rating is given as a percentage (20% in the comic), then a reduction of 19% has two possible meanings:
:1) Of the 20% who previously approved (200,000 people), 19% no longer approve. In this case the result is 162,000 as in the above example.
:2) Compared to the original results, 19% fewer of the entire original sample of 1 million people approve. In this case only 1% of the original 1 million approve, equal to 10,000 people.

If using the second method of comparing percentages, the approvals rating should be described as having dropped by 19 percentage points. In reality, the distinction between the two methods is often overlooked, leading to confusion.

The caption's issue with "percentage" versus "percentage points" is that if Grayton's 20% approval rating drops by 19%, that means that his support has only dropped 3.8 percentage points since 19% of 20% is only 3.8%. That would mean that even after all his outrageous statements, his support dropped only from 20% to 16.2%. However, if the news reports that his 20% approval rating dropped 19 ''percentage points'', that means his support has dropped to 1%, which appears to be more accurate given Grayton's egregious policy decisions and the description of his campaign as having "imploded."

The punchline to all this is that Randall is more bothered by the "percent" ambiguity than by Grayton's appalling policy plans.

References in the title text:

*{{w|Tracy Morgan}} is an actor who plays Tracy Jordan in the TV Show ''{{w|30 Rock}}''. He has been reprimanded for controversial comments on homosexuals and {{w|Sarah Palin}} (in separate incidents).
*{{w|John Wilkes Booth}} is the person who assassinated {{w|Abraham Lincoln}}. He was a {{w|Confederate}} sympathizer and supported slavery. The mention of his ghost could also be a reference to King Falls AM, an audio drama which features his ghost multiple times.
*"The {{w|Time Cube}} Guy" would be Otis Eugene "Gene" Ray. To put things ''very'' politely (as Mr. Ray was a very angry man with severe schizophrenia), he created a website known as Time Cube where he set out his personal model of reality, which he called Time Cube. He suggested that all of modern physics is wrong, in addition to claiming that religion is evil, specifically Christianity, and that the idea of family is poisoning children. Ray passed away in 2015.
*College scholarships to sexually active teens: Many people think adolescents should not engage in sexual activity, let alone be encouraged to do so by college scholarships. This is the opposite of {{w|Abstinence-only sex education|abstinence programs}}, which encourage teens not to be sexually active until marriage.
*Illegal immigrants who create room for themselves by killing a citizen: {{w|Illegal immigration to the United States|Illegal immigration}} is a highly controversial topic in the United States. One argument against illegal immigration is that illegal immigrants are taking jobs away from American citizens. Proponents of immigration assert that this is not the case, since more people in the overall economy creates jobs and brings in more tax revenue. Neither group would be in favor of illegal immigrants murdering citizens even though it would not result in a net gain or loss in population.
*Graduated income tax based on penis size: Many men are sensitive about their penis size and would probably consider the measurement of their penises for tax assessment purposes an enormous embarrassment and invasion of privacy. Even the scenario in which those with relatively smaller penises would be levied less tax than those with larger penises would probably not be sufficient for them to accept this policy, and even if they did, those with larger penises would probably consider this policy to be unfair. And the alternative—a scenario in which ''larger'' penises pay less taxes—would be both unfair and incredibly demeaning. Not to mention, it is also entirely unclear as to how tax laws would apply to women in this scenario.

==Transcript==
:[Cueball is sitting in an armchair watching TV while listening to a news report coming from the TV as shown by a zigzag line.]
:Voice from TV: Senator Grayton's campaign has imploded following the candidate's promise to give tax breaks to drunk drivers and to authorize the use of unmanned Predator drones in the War On Christmas. Grayton had been polling at 20%, but his support has since plunged by 19%.

:[Caption below the panel:]
:I hate the ambiguity created when people don't distinguish between percentages and percentage points.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring real people]] 
[[Category:Politics]]
[[Category:Math]]
[[Category:Penis]]