explain xkcd - User contributions [en]

3097: Bridge Types

2025-06-03T06:06:45Z

172.68.22.41:

{{comic
| number = 3097
| date = June 2, 2025
| title = Bridge Types
| image = bridge_types_2x.png
| imagesize = 740x581px
| noexpand = true
| titletext = Pontoon bridges are just linear open-sided waterbeds.
}}

==Explanation==
{{incomplete|This page was recently created by a RAINBOW BRIDGE. Don't remove this notice too soon.}}
This comic shows, in a four-by-four grid of images, a series of bridge types. The first two rows of images are of authentic bridges, whereas those in the last two rows are progressively more absurd. The joke lies in the progression of bridge types from simple to realistically complex to totally bogus.

{| class="wikitable"
!Label
!Status
!Type
!Notes
|-
|Plank
|Real
|{{w|Timber_bridge|Timber Bridge}}
|TBD
|-
|Rope
|Real
|{{w|Simple_suspension_bridge|Simple suspension bridge}}
|TBD
|-
|Truss
|Real
|
|TBD
|-
|Trestle
|Real
|
|TBD
|-
|Arch
|Real
|
|TBD
|-
|Suspended Arch
|Real
|
|TBD
|-
|Draw
|Real
|
|TBD
|-
|Suspension
|Real
|
|TBD
|-
|Filler
|Real (Absurd Name)
|
|TBD
|-
|Budget Overrun
|Real (Absurd Name)
|
|TBD
|-
|Jump
|Not Real
|N/A
|TBD
|-
|Halfhearted
|Not Real
|N/A
|TBD
|-
|Waterbed
|Not Real
|N/A
|TBD
|-
|L'Engle
|Not Real
|
|TBD
|-
|Fun
|Not Real
|
|TBD
|-
|Repurposed Elevator
|Not Real
|
|TBD
|}

The first image in the third row purports to represent a "filler" bridge. Unlike the other "bridges" in the third and fourth rows, this image represents a real construction, though it is more appropriately known as a {{w|Causeway|causeway}}. Searches on "filler bridge" call up various forms of {{w|Rhinoplasty|rhinoplasty}}, or "nose jobs". The pun may or may not be intentional.

The second image in the third row is labeled "Budget overrun". The somewhat outlandishly-designed {{w|Cable-stayed_bridge|cable-stayed bridge}} shown bears some resemblance to the {{w|Leonard_P._Zakim_Bunker_Hill_Memorial_Bridge|Zakim bridge}} over the Charles River in downtown Boston, close to where cartoonist Randall resides. The Zakim Bridge is one of the most conspicuous elements of Boston's {{w|Big_Dig|"Big Dig"}} project, notorious for its size, cost (double the original budget) and poor execution at many levels.

The second image in the fourth row is labeled "L'Engle". This is a reference to the young-adult novel {{w|A Wrinkle In Time}} by Madeleine L'Engle. In it, characters are told about crossing great distances by "tessering", moving via a tesseract through a higher dimension which essentially brings the two ends of the journey together from the perspective of the traveler. The image shows the two ends of the gap being brought together, with the gap apparently crumpled in between them.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}

{{comic discussion}}<noinclude>

[[Category:Engineering]]
[[Category:Multiple Cueballs]]

3094: Mass Spec

2025-05-27T05:59:40Z

172.68.22.41:

{{comic
| number = 3094
| date = May 26, 2025
| title = Mass Spec
| image = mass_spec_2x.png
| imagesize = 407x253px
| noexpand = true
| titletext = Patients at least found it to be an improvement over Millikan's incredibly messy and unpleasant oil drop suspension procedure.
}}

==Explanation==
{{incomplete|This page was created by HARVEY FLETCHER (UNCREDITED). Don't remove this notice too soon.}}
In the early 1920s, the domestic bathroom scale (initially a form of {{w|Spring_scale|spring scale}}) was introduced to customers in the United States of America. The device soon became popular, and has remained so to the present. Although means to ascertain the weight of the human body existed before the 1920s, they were not in common use, and were not thought necessary in routine physical / medical examinations.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}

{{comic discussion}}<noinclude>

3085: About 20 Pounds

2025-05-07T19:06:56Z

172.68.22.41: /* Explanation */ brief explanation of dark matter

{{comic
| number = 3085
| date = May 5, 2025
| title = About 20 Pounds
| image = about_20_pounds_2x.png
| imagesize = 666x278px
| noexpand = true
| titletext = In addition to gravity, burritos interact through the strong, weak, and electromagnetic forces, which is believed to be a major contributor to their popularity.
}}

==Explanation==
{{incomplete|Created by a £20 20-LB PARTICLE. Are any categories missing? Don't remove this notice too soon.}}

The nature of {{w|dark matter}} is a significant unsolved problem in physics. We observe that galaxies spin faster than we expect based on the nearby observable matter. Likewise galactic motions indicate additional mass that we have not observed in other ways. Dark matter is the name we give to this mass. In the comic, [[Cueball]] and [[Ponytail]] consult an {{w|oracle}} to learn about dark matter.

The pentacle and candles suggest that the oracle is supernatural, summoned by an occult ritual; something which would present its own challenges to our understanding of the physical world. There may be a pun here, in that they may be using 'dark magic' to communicate with something from the 'dark realm' on the assumption that it will know about dark matter. However, the word 'dark' in dark matter simply means that we do not know how to observe it; we have no evidence that dark matter is evil or satanic (though [[Randall]] may consider it [[:Category:Comics with cursed items|cursed]]). The oracle is used very similarly to how people have been using and customizing {{w|large language model|large language models}}.

In general, not all forces interact with all particles; indeed, {{w|gravity}} is believed to be the only force that interacts with everything we have observed. If a force doesn't interact with a particle, then the particles existence cannot be directly observed via disturbances in that force. In particular, something that doesn't interact with electromagnetism cannot be 'seen', as photons will pass through it relatively unaffected, and likewise cannot be felt, because collision is a side effect of the {{w|Pauli exclusion principle}}.

Even {{w|neutrino}}s—famous for {{what if|73|interacting with ''almost'' nothing}}—still interact via the {{w|weak force}}, allowing them to be detected with sufficiently large tanks of dense material (as most atoms interact with the weak force, however weakly). A particle that interacts with ''nothing'' except gravity could only be detected by a {{w|LIGO|gravitational telescope}}.

However, even if a particle does interact via a given force, an interaction is possible only if energy is conserved. If dark matter is entirely due to a single kind of particle with the fundamental mass of ''about twenty pounds'' (a rather vague measurement, in the rough vicinity of 10 kilograms, but in line with how apparently all-knowing oracles legendarily avoid unambiguous statements), this is an absolutely ludicrous amount of energy for particle physics. Any interaction would have to involve an equally ludicrous amount of other particle mass being in exactly the right place and time, a coincidence that could easily reach "never in the history of the universe" levels. By comparison, the {{w|top quark}}, the heaviest single particle we have observed, with a mass over a hundred times that of the proton, is still nevertheless around a tenth of a trillionth of a trillionth of a pound.

Under more normal circumstances, we might still hope to observe the properties of the particle via creating it ourselves under controlled laboratory conditions. But again, there is no reasonable way to focus the energy required into a single particle interaction. The {{w|Large Hadron Collider|most powerful particle accelerator in the world}}, for example, peaks at about ten thousand times the mass of the proton—a solid billion times less energy than required—so it's out too.

Despite all this, twenty pounds is also much too ''small'' to be detectable via gravitational interaction—its {{w|Perturbation (astronomy)|influence on the orbits of planets}}, say, or the strength of its {{w|gravitational lensing}} effect, would be entirely negligible. Thus in the scenario posed by the comic, there is no plausible way to observe more about dark matter while on Earth. Even if we did find some such particles naturally occurring, and had instruments that could measure such small gravitational forces, since it would interact only via gravity, the only properties it could have other than mass would be its decay rates from other particles—which, again, would all be essentially nil due to its mass.

The oracle proceeds to break expectations by suggesting that Ponytail and Cueball go out for {{w|burrito|burritos}}, something generally considered non-scientific.{{cn}} When faced with the apparent futility of continuing to try to investigate dark matter, the oracle predicts that going out for burritos is precisely as productive as any other approach—i.e., not at all. It justifies the suggestion by burritos being "pretty" good, again neither exactly quantifying the oracularity, and likely not even giving the optimal idea (for choice of food, or of any other "what now?" diversion that it might give).

The title text observes that burritos interact through all four known {{w|fundamental interactions}}, making burritos popular. The electromagnetic force mediates the chemical reactions leading to a burrito's taste, the strong force keeps atomic nuclei together, and gravity gives burritos heft, all of which are helpful for enjoying them. It's hard to see how the weak force, which takes part in radioactive decay, helps with burrito enjoyment or popularity, but the weak force is responsible for the nuclear fusion that allowed the complex elements of the burrito to exist in the first place.

The previous comic [[3084: Unstoppable Force and Immovable Object]] dealt with particles which do not even interact with gravity.

==Transcript==
:[Cueball and Ponytail are standing in front of a pentacle with lit candles at the corners. A black sphere, the oracle, is floating above the middle of the pentacle.]
:Ponytail: Dear oracle,
:Ponytail: What is the nature of dark matter?
:Oracle: It's about 20 pounds.

:[Close up of oracle]
:Off-panel: What?
:Oracle: Dark matter is a particle. It weighs about 20 pounds.
:Oracle: It only interacts through gravity.

:[Same view as first panel]
:Cueball: Only gravity, huh?
:Cueball: So none of our experiments are really going to tell us any more about it, then.
:Oracle: Afraid not.

:[Same view as first and third panels, except Cueball lifted his forearm.]
:Cueball: So what do we do?
:Oracle: You should go out for burritos.
:Ponytail: How will that help?
:Oracle: Well
:Oracle: Burritos are pretty good.

{{comic discussion}}<noinclude>
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Physics]]
[[Category:Food]]

3085: About 20 Pounds

2025-05-07T18:53:36Z

172.68.22.41: /* Explanation */ similar comic - 3084: Unstoppable Force and Immovable Object

{{comic
| number = 3085
| date = May 5, 2025
| title = About 20 Pounds
| image = about_20_pounds_2x.png
| imagesize = 666x278px
| noexpand = true
| titletext = In addition to gravity, burritos interact through the strong, weak, and electromagnetic forces, which is believed to be a major contributor to their popularity.
}}

==Explanation==
{{incomplete|Created by a £20 20-LB PARTICLE. Are any categories missing? Don't remove this notice too soon.}}

The nature of {{w|dark matter}} is a significant unsolved problem in physics. In the comic, [[Cueball]] and [[Ponytail]] consult an {{w|oracle}} to learn about dark matter. The pentacle and candles suggest occult rituals have been used to summon something supernatural; something which would present its own challenges to our understanding of the physical world. There may be a pun here, in that they may be using 'dark magic' to communicate with something from the 'dark realm' on the assumption that it will know about dark matter. However, the word 'dark' in dark matter simply means that we do not know how to observe it; we have no evidence that dark matter is evil or satanic (though [[Randall]] may consider it [[:Category:Comics with cursed items|cursed]]). The oracle is used very similarly to how people have been using and customizing {{w|large language model|large language models}}.

In general, not all forces interact with all particles; indeed, {{w|gravity}} is believed to be the only force that interacts with everything we have observed. If a force doesn't interact with a particle, then the particles existence cannot be directly observed via disturbances in that force. In particular, something that doesn't interact with electromagnetism cannot be 'seen', as photons will pass through it completely unaffected, and likewise cannot be felt, because collision is a side effect of the {{w|Pauli exclusion principle}}.

Even {{w|neutrino}}s—famous for {{what if|73|interacting with ''almost'' nothing}}—still interact via the {{w|weak force}}, allowing them to be detected with sufficiently large tanks of dense material (as most atoms interact with the weak force, however weakly). A particle that interacts with ''nothing'' except gravity could only be detected by a {{w|LIGO|gravitational telescope}}.

However, even if a particle does interact via a given force, an interaction is possible only if energy is conserved. If dark matter is entirely due to a single kind of particle with the fundamental mass of ''about twenty pounds'' (a rather vague measurement, in the rough vicinity of 10 kilograms, but in line with how apparently all-knowing oracles legendarily avoid unambiguous statements), this is an absolutely ludicrous amount of energy for particle physics. Any interaction would have to involve an equally ludicrous amount of other particle mass being in exactly the right place and time, a coincidence that could easily reach "never in the history of the universe" levels. By comparison, the {{w|top quark}}, the heaviest single particle we have observed, with a mass over a hundred times that of the proton, is still nevertheless around a tenth of a trillionth of a trillionth of a pound.

Under more normal circumstances, we might still hope to observe the properties of the particle via creating it ourselves under controlled laboratory conditions. But again, there is no reasonable way to focus the energy required into a single particle interaction. The {{w|Large Hadron Collider|most powerful particle accelerator in the world}}, for example, peaks at about ten thousand times the mass of the proton—a solid billion times less energy than required—so it's out too.

Despite all this, twenty pounds is also much too ''small'' to be detectable via gravitational interaction—its {{w|Perturbation (astronomy)|influence on the orbits of planets}}, say, or the strength of its {{w|gravitational lensing}} effect, would be entirely negligible. Thus in the scenario posed by the comic, there is no plausible way to observe more about dark matter while on Earth. Even if we did find some such particles naturally occurring, and had instruments that could measure such small gravitational forces, since it would interact only via gravity, the only properties it could have other than mass would be its decay rates from other particles—which, again, would all be essentially nil due to its mass.

The oracle proceeds to break expectations by suggesting that Ponytail and Cueball go out for {{w|burrito|burritos}}, something generally considered non-scientific.{{cn}} When faced with the apparent futility of continuing to try to investigate dark matter, the oracle predicts that going out for burritos is precisely as productive as any other approach—i.e., not at all. It justifies the suggestion by burritos being "pretty" good, again neither exactly quantifying the oracularity, and likely not even giving the optimal idea (for choice of food, or of any other "what now?" diversion that it might give).

The title text observes that burritos interact through all four known {{w|fundamental interactions}}, making burritos popular. The electromagnetic force mediates the chemical reactions leading to a burrito's taste, the strong force keeps atomic nuclei together, and gravity gives burritos heft, all of which are helpful for enjoying them. It's hard to see how the weak force, which takes part in radioactive decay, helps with burrito enjoyment or popularity, but the weak force is responsible for the nuclear fusion that allowed the complex elements of the burrito to exist in the first place.

The previous comic [[3084: Unstoppable Force and Immovable Object]] dealt with particles which do not even interact with gravity.

==Transcript==
:[Cueball and Ponytail are standing in front of a pentacle with lit candles at the corners. A black sphere, the oracle, is floating above the middle of the pentacle.]
:Ponytail: Dear oracle,
:Ponytail: What is the nature of dark matter?
:Oracle: It's about 20 pounds.

:[Close up of oracle]
:Off-panel: What?
:Oracle: Dark matter is a particle. It weighs about 20 pounds.
:Oracle: It only interacts through gravity.

:[Same view as first panel]
:Cueball: Only gravity, huh?
:Cueball: So none of our experiments are really going to tell us any more about it, then.
:Oracle: Afraid not.

:[Same view as first and third panels, except Cueball lifted his forearm.]
:Cueball: So what do we do?
:Oracle: You should go out for burritos.
:Ponytail: How will that help?
:Oracle: Well
:Oracle: Burritos are pretty good.

{{comic discussion}}<noinclude>
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Physics]]
[[Category:Food]]

3085: About 20 Pounds

2025-05-07T18:48:48Z

172.68.22.41: /* Explanation */ simplify sentences, remove excess words

{{comic
| number = 3085
| date = May 5, 2025
| title = About 20 Pounds
| image = about_20_pounds_2x.png
| imagesize = 666x278px
| noexpand = true
| titletext = In addition to gravity, burritos interact through the strong, weak, and electromagnetic forces, which is believed to be a major contributor to their popularity.
}}

==Explanation==
{{incomplete|Created by a £20 20-LB PARTICLE. Are any categories missing? Don't remove this notice too soon.}}

The nature of {{w|dark matter}} is a significant unsolved problem in physics. In the comic, [[Cueball]] and [[Ponytail]] consult an {{w|oracle}} to learn about dark matter. The pentacle and candles suggest occult rituals have been used to summon something supernatural; something which would present its own challenges to our understanding of the physical world. There may be a pun here, in that they may be using 'dark magic' to communicate with something from the 'dark realm' on the assumption that it will know about dark matter. However, the word 'dark' in dark matter simply means that we do not know how to observe it; we have no evidence that dark matter is evil or satanic (though [[Randall]] may consider it [[:Category:Comics with cursed items|cursed]]). The oracle is used very similarly to how people have been using and customizing {{w|large language model|large language models}}.

In general, not all forces interact with all particles; indeed, {{w|gravity}} is believed to be the only force that interacts with everything we have observed. If a force doesn't interact with a particle, then the particles existence cannot be directly observed via disturbances in that force. In particular, something that doesn't interact with electromagnetism cannot be 'seen', as photons will pass through it completely unaffected, and likewise cannot be felt, because collision is a side effect of the {{w|Pauli exclusion principle}}.

Even {{w|neutrino}}s—famous for {{what if|73|interacting with ''almost'' nothing}}—still interact via the {{w|weak force}}, allowing them to be detected with sufficiently large tanks of dense material (as most atoms interact with the weak force, however weakly). A particle that interacts with ''nothing'' except gravity could only be detected by a {{w|LIGO|gravitational telescope}}.

However, even if a particle does interact via a given force, an interaction is possible only if energy is conserved. If dark matter is entirely due to a single kind of particle with the fundamental mass of ''about twenty pounds'' (a rather vague measurement, in the rough vicinity of 10 kilograms, but in line with how apparently all-knowing oracles legendarily avoid unambiguous statements), this is an absolutely ludicrous amount of energy for particle physics. Any interaction would have to involve an equally ludicrous amount of other particle mass being in exactly the right place and time, a coincidence that could easily reach "never in the history of the universe" levels. By comparison, the {{w|top quark}}, the heaviest single particle we have observed, with a mass over a hundred times that of the proton, is still nevertheless around a tenth of a trillionth of a trillionth of a pound.

Under more normal circumstances, we might still hope to observe the properties of the particle via creating it ourselves under controlled laboratory conditions. But again, there is no reasonable way to focus the energy required into a single particle interaction. The {{w|Large Hadron Collider|most powerful particle accelerator in the world}}, for example, peaks at about ten thousand times the mass of the proton—a solid billion times less energy than required—so it's out too.

Despite all this, twenty pounds is also much too ''small'' to be detectable via gravitational interaction—its {{w|Perturbation (astronomy)|influence on the orbits of planets}}, say, or the strength of its {{w|gravitational lensing}} effect, would be entirely negligible. Thus in the scenario posed by the comic, there is no plausible way to observe more about dark matter while on Earth. Even if we did find some such particles naturally occurring, and had instruments that could measure such small gravitational forces, since it would interact only via gravity, the only properties it could have other than mass would be its decay rates from other particles—which, again, would all be essentially nil due to its mass.

The oracle proceeds to break expectations by suggesting that Ponytail and Cueball go out for {{w|burrito|burritos}}, something generally considered non-scientific.{{cn}} When faced with the apparent futility of continuing to try to investigate dark matter, the oracle predicts that going out for burritos is precisely as productive as any other approach—i.e., not at all. It justifies the suggestion by burritos being "pretty" good, again neither exactly quantifying the oracularity, and likely not even giving the optimal idea (for choice of food, or of any other "what now?" diversion that it might give).

The title text observes that burritos interact through all four known {{w|fundamental interactions}}, making burritos popular. The electromagnetic force mediates the chemical reactions leading to a burrito's taste, the strong force keeps atomic nuclei together, and gravity gives burritos heft, all of which are helpful for enjoying them. It's hard to see how the weak force, which takes part in radioactive decay, helps with burrito enjoyment or popularity, but the weak force is responsible for the nuclear fusion that allowed the complex elements of the burrito to exist in the first place.

==Transcript==
:[Cueball and Ponytail are standing in front of a pentacle with lit candles at the corners. A black sphere, the oracle, is floating above the middle of the pentacle.]
:Ponytail: Dear oracle,
:Ponytail: What is the nature of dark matter?
:Oracle: It's about 20 pounds.

:[Close up of oracle]
:Off-panel: What?
:Oracle: Dark matter is a particle. It weighs about 20 pounds.
:Oracle: It only interacts through gravity.

:[Same view as first panel]
:Cueball: Only gravity, huh?
:Cueball: So none of our experiments are really going to tell us any more about it, then.
:Oracle: Afraid not.

:[Same view as first and third panels, except Cueball lifted his forearm.]
:Cueball: So what do we do?
:Oracle: You should go out for burritos.
:Ponytail: How will that help?
:Oracle: Well
:Oracle: Burritos are pretty good.

{{comic discussion}}<noinclude>
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Physics]]
[[Category:Food]]

2936: Exponential Growth

2025-04-29T20:09:07Z

172.68.22.41: /* Explanation */ 3082:_Chess_Position

{{comic
| number = 2936
| date = May 22, 2024
| title = Exponential Growth
| image = exponential_growth_2x.png
| imagesize = 545x264px
| noexpand = true
| titletext = Karpov's construction of a series of increasingly large rice cookers led to a protracted deadlock, but exponential growth won in the end.
}}

==Explanation==

In this strip Black Hat begins by demonstrating {{w|exponential growth}}, using a variation of the {{w|wheat and chessboard problem}}, a classic demonstration of this mathematical principle. Exponential growth involves an initial quantity being multiplied by any number greater than one again and again. It can cause small numbers to compound into very large numbers faster than might be intuitive. This principle is important in a number of real life applications, ranging from biological growth to inflation to reaction kinetics.

The earliest versions of this story come from India and involve a man (the inventor of {{w|chess}}, in some tellings), being offered a reward by a king, and asking that a single grain of wheat (rice, in some versions) be placed on the first square of a chessboard, two on the second, and each subsequent square having twice as many grains as the one before. In the story, the king generally laughs off such a reward as being trivial, but soon learns that the reward would be impossible to pay. Since a chessboard contains 64 squares, the final square would contain 263 (9,223,372,036,854,775,808) grains. This would be around 600 billion tonnes of wheat (even in modern times, would be centuries of global wheat production).

In some versions of the story, the man is executed for embarrassing the king and/or being over-greedy; in others, he's rewarded for his cleverness; in yet others he becomes king himself as a consequence. There are also other versions that [https://www.comedy.co.uk/radio/finnemore_souvenir_programme/episodes/7/5/ subvert the well-known tale] by the king not being so naïve as to fall for the 'trick' played by the creator of the problem.

[[Black Hat]] initially appears to be using this example, to demonstrate a mathematical principle, but actually turns out to be using it to "win" a chess match by covering the chess board in rice until his opponent quits out of frustration. Naturally, despite his claims that it's "nearly impossible to counter", under the International Chess Federation ({{w|FIDE}})'s [https://www.fide.com/FIDE/handbook/LawsOfChess.pdf Laws of Chess], this would be illegal on several levels, as deliberately distracting or annoying your opponent is a violation, as is deliberately displacing the chess pieces. Black Hat being the chaotic [[classhole]] that he is, he likely simply doesn't care, and counts it as a win when his opponent stomps off out of annoyance.

{{w|Garry Kasparov}} and {{w|Anatoly Karpov}} are both Russian chess grandmasters and former world champions. The two men famously competed for the world championship in the 1980s. The Kasparov gambit is a famous gambit that Kasparov played multiple times (but not, as Black Hat's is, something that can be played very early in the game). The title text implies that Kasparov actually tried Black Hat's method on Karpov, who attempted to consume all the rice with "increasingly large rice cookers", but eventually couldn't keep up. While this is obviously fictional,{{cn}} it fits with the principle of exponential growth. If exponential growth is unrestricted, it will eventually grow beyond the constraints of anything that could plausibly be built to contain it.

In any case, it appears that in his enthusiasm to enact his scheme, Black Hat has neglected to even set up his own pieces (or they have already been completely buried), never mind wait for the game to commence, so his opponent has nothing to resign from - indeed his king still appears to be standing as he walks away.

Another Kasparov gambit is mentioned in [[3082:Chess Position]].

==Math==

The amount of rice collected on each square of the chess board is listed below. It all sums up to around 400 billion tons (or {{w|tonne}}s, the various distinctions being not so important), taking each grain as weighing approximately 0.02 grams. This is 500 times the annual world production.

The last day, alone, would require 200 billion tons. But the implicit nature of this doubling is that the amount of rice you put on at any stage is exactly equal to the amount of rice already on the board ''plus one extra grain''. So there were around 200 billion tons already, before the last square required a virtually identical additional amount.

* First row:
** a1: 1 grain
** a2: 2 grains
** a3: 4 ...
** a4: 8
** a5: 16
** a6: 32
** a7: 64
** a8: 128
* Second row
** b1: 256
** b2: 512
** b3: 1,024
** b4: 2,048
** b5: 4,096
** b6: 8,192
** b7: 16,384
** b8: 32,768
* First column of third to seventh rows
** c1: 65,536 grains (~ 1 kg)
** d1: 16,777,216 (~ 400 kg)
** e1: 4,294,967,296 (~ 100 tons)
** f1: 1,099,511,627,776 (~ 25,000 tons)
** g1: 281,474,976,710,656 (~ 6 million tons)
* Eighth row, in detail
** h1: 72,057,594,037,927,936 (~ 1.5 billion tons, more than the 2022 world harvest)
** h2: 144,115,188,075,855,872
** h3: 288,230,376,151,711,744
** h4: 576,460,752,303,423,488
** h5: 1,152,921,504,606,846,976
** h6: 2,305,843,009,213,693,952
** h7: 4,611,686,018,427,387,904
** h8: 9,223,372,036,854,775,808 (~ 200 billion tons)
* Total: 18,446,744,073,709,551,615

[https://upload.wikimedia.org/wikipedia/commons/e/e7/Wheat_Chessboard_with_line.svg Example on the chessboard (SVG diagram)]

==Transcript==

:[Black Hat is talking to Cueball standing next to him, arm raised.]
:Black Hat: Exponential growth is very powerful.

:[Closeup on Black Hat. Next to him is an image of the lower left part of a chessboard. The four leftmost squares in the bottom row have grains of rice on them -- one, two, four, and eight grains respectively.]
:Black Hat: A chessboard has 64 squares.
:Black Hat: Say you put one grain of rice on the first square, then two grains on the second, then four, then eight, doubling each time.

:[Black Hat has emptied a bag of rice on a chessboard. There are two additional bags next to him, each labeled "Rice", and a pile of rice already on the table. Some rice has spilled off, and a small pile of rice is growing at Black Hat's feet. A frustrated Hairy is walking away, fists clenched. On Hairy's side of the chessboard there is a white king and pawn.]
:[Caption above panel, representing Black Hat continuing to speak:]
:If you keep this up, your opponent will resign in frustration.
:It's called Kasparov's Grain Gambit. Nearly impossible to counter.

{{comic discussion}}

[[Category:Comics featuring Black Hat]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Hairy]]
[[Category:Chess]]
[[Category:Math]]
[[Category:Food]]
[[Category:Comics featuring real people]]

Talk:3082: Chess Position

2025-04-29T04:56:21Z

172.68.22.41:

This is very nearly the core plot conceit of the movie ''Π'' (1998). [[Special:Contributions/172.70.130.190|172.70.130.190]] 22:36, 28 April 2025 (UTC)
:I believe you want lower-case Pi: π not Π. https://en.wikipedia.org/wiki/Pi_(film) --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 22:54, 28 April 2025 (UTC)

Does anybody know whether Randall has taken up chess as a hobby? 5 of the 82 comics in the 3000s have been related to chess and only 2 in the 2000s were. If so, this should be included in the explanation. [[User:BobcatInABox|BobcatInABox]] ([[User talk:BobcatInABox|talk]]) 23:11, 28 April 2025 (UTC)
:3000s? [[Special:Contributions/172.71.190.236|172.71.190.236]] 23:40, 28 April 2025 (UTC)
:Oh right comic number not decade/millennium. [[Special:Contributions/172.70.43.157|172.70.43.157]] 23:41, 28 April 2025 (UTC)
:Wouldn't surprise me, there's a three year gap in between chess comics 2465 (May 2021) and 2936 (May 2024), then the aforementioned 5 in 5 months. [[Special:Contributions/172.70.114.251|172.70.114.251]] 00:46, 29 April 2025 (UTC)

I really suspect that the full explanation has something to do with this:

https://www.kasparov.com/the-implacable-logic-of-the-vortex-of-history/
[[Special:Contributions/172.68.7.206|172.68.7.206]] 23:34, 28 April 2025 (UTC) Dan
: Doubtful, that article was written in 2013, and it is unlikely that Randall came upon it just now to make this comic. Vortex is a general term for something that sucks you in. [[Special:Contributions/172.70.214.66|172.70.214.66]] 00:38, 29 April 2025 (UTC)

I sure hope that it stays as not a real thing [[User:Commercialegg|Commercialegg]] ([[User talk:Commercialegg|talk]]) 01:32, 29 April 2025 (UTC)
: It might not be, but it's easy enough to make: Train an adversarial network on human chess games. [[Special:Contributions/172.68.22.41|172.68.22.41]] 04:56, 29 April 2025 (UTC)

The part about losing the ability to play chess even after building a resistance feels familiar. Isn't that how the Elder Scrolls worked in Skyrim, at least. Even highly trained sages would lose the ability to see for a time after reading an Elder Scroll. And the Oblivion remaster just released the other day...
--[[User:Ragashingo|Ragashingo]] ([[User talk:Ragashingo|talk]]) 01:54, 29 April 2025 (UTC)

Talk:3081: PhD Timeline

2025-04-26T02:15:44Z

172.68.22.41:

What an age we live in... --[[User:DollarStoreBa'al |DollarStoreBa'al]][[User talk:DollarStoreBa'al | Converse]][https://www.explainxkcd.com/wiki/index.php/Special:Contributions/DollarStoreBa%27al My life choices] 15:48, 25 April 2025 (UTC)
:[https://www.cnn.com/2025/04/25/politics/fbi-director-wisconsin-judge-arrested/index.html It only gets rougher... ] It's enough to radicalize a person. [[Special:Contributions/172.69.65.187|172.69.65.187]] 16:09, 25 April 2025 (UTC)
:When even Randall starts freaking out, it usually indicates the most entertaining timeline. [[Special:Contributions/162.158.245.161|162.158.245.161]] 00:58, 26 April 2025 (UTC)

Events like this are scary, and they're even scarier if you have a personal or geographic connection to them like Randall does. I can understand why he would feel frustrated about his inability to do something concrete, and if this comic raises awareness for the situation then it has done a good thing. Not sure why I thought this comment was necessary; maybe it's just a way of processing the emotions that the comic made me feel. [[User:Dextrous Fred|Dextrous Fred]] ([[User talk:Dextrous Fred|talk]]) 15:49, 25 April 2025 (UTC)

I dont want to start an argument, but I am glad Randall Munroe is making a specific, reasonable point. A lot of times I see people saying either "there is no antisemitism on campus, nobody should ever get deported, ACTUAL terrorists should get green cards", and others say "EVERYONE WHO DISAGREES WITH ME SHOULD GET DEPORTED, EVERYONE WHO DISAGREES WITH ME IS A TERRORIST." I think both of them are extreme points obviously, and I am glad Randall is just taking the side, for now, of "this specific person did not violate their green card visa."

:Hi, expert-on-the-Öztürk-case but not-an-immigration-expert-really here. For clarity, Öztürk held an F-1 student visa but was not a lawful permanent resident (LPR) (green card holder), unlike the similar case of Mahmoud Khalil (Columbia university) who was a green card holder. And "green card visa" is not a thing, there's a "green card," which you cannot "violate" (although you could commit crimes that might have consequences for your LPR status), and you generally don't hear "violate their visa" although it's true that a visa is related to and may restrict that work you can do in the country. Regardless, no allegations have been made that Öztürk violated anything laws or rules or did anything other than lend her name to speech in a newspaper. [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 22:51, 25 April 2025 (UTC)

as always, based randall, at least for now. [[User:Tzelofachad|Tzelofachad]] ([[User talk:Tzelofachad|talk]]) 16:04, 25 April 2025 (UTC)
:Did you mean "biased"? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 16:31, 25 April 2025 (UTC)
::Did you mean "biased towards due process?" [[User:CharlesT|Nyrrix]] ([[User talk:CharlesT|talk]]) 16:51, 25 April 2025 (UTC)
::It's probably "based", as that's a term that can either be used in support or mockery of a philosophical position (because of Poe's Law, hard to know which in most cases, including here). It's more usually used in 4chan-like responses (and I doubt Randall would be considered "based" in those other places) than hereabouts, so perhaps it needs some clarification for those not (or not enough) in that sort of crame of mind. [[Special:Contributions/141.101.99.94|141.101.99.94]] 17:06, 25 April 2025 (UTC)
:Yes, Randall Munroe clearly only cares about this one incident because he does not at all care about politics. He's definitely not using this as an illustrative case on the countless other identical incidents happening under the Trump administration. /s /s /s /s /s. [[User:DrMeepster|'''Dr.'''Meepster]]
(<[[User_talk:DrMeepster|chat]]> •
<[{{fullurl:{{FULLPAGENAME}}|action=edit}} reply]>) 16:53, 25 April 2025 (UTC)

I really hope this is one of those comics that does NOT stand the test of time. In other words, I hope the next generation of graduate students sees this and thinks "oh, that must've been written in 2025, we don't have to worry about those kinds of things anymore." Perhaps "hope" isn't the right word, it implies I have hope. Maybe "pray fervently" is the right phrase. Sigh. [[Special:Contributions/198.41.227.72|198.41.227.72]] 16:30, 25 April 2025 (UTC)
:Sure ... "Oh, that was before third world war, we don't have to worry about those kinds of things anymore." -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 00:08, 26 April 2025 (UTC)
:We can go back to considering how the Ph.D. became a participation trophy for the financial benefit of the awarding institution - and, in the sciences, a source of slave labor. [[Special:Contributions/172.71.146.61|172.71.146.61]] 01:51, 26 April 2025 (UTC)

How do we edit the Categories? This should have category Politics. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 16:31, 25 April 2025 (UTC)
:Usually, once at least one other category (not created from templates like {{template|comic}}) you can edit the page and see the other cat(s) at the bottom, beyond the comic-discussion template. Or edit the Transcript section (or any Trivia one, whatever's the last one) as that'll also have the tail-end of the page. So long as you know there's a category "Foo", you should be able to work out how to add "Category:Foo".
:But don't add Foo if it doesn't exist, hoping that someone will tire of the redlink that's created. You may be wrong about it needing to exist, or miss the ''actual'' "Category:comics featuring Foo", and unless someone is feeling generous it's possible that your edit just gets reverted as not properly researched, or checked... I ''think'' there actually is a Politics category, by that name, but I'm trying to answer the general question, not yet going out there to look it up for certain (at which point, I may have just added it myself, making it useless to have explained how you could 'easily' do it... At least in this instance).
:'''TL;DR;''', though, look at the source (wiki-edit) of another comic that is about Politics and is so categorised. Go all the way to bottom, and you'll see which 'tag' you might want to put at the bottom of this one. Should be obvious. [[Special:Contributions/141.101.99.94|141.101.99.94]] 17:06, 25 April 2025 (UTC)
I think I've added that category now [[Special:Contributions/104.23.190.60|104.23.190.60]] 19:33, 25 April 2025 (UTC)

I'm so tired of this administration :( [[User:CharlesT|Nyrrix]] ([[User talk:CharlesT|talk]]) 16:49, 25 April 2025 (UTC)
:Are you a citizen of the USA? If so, are you dead? In exile? In jail? Have your assets been seized? No to these? Then this is your administration and mine. Own it, or act. "Tired" doesn't cut it. [[Special:Contributions/172.71.147.21|172.71.147.21]] 02:02, 26 April 2025 (UTC)

The comic on mobile has the title text has a youtube video URL, and if you click on the comic on desktop version, it links to the youtube video of the arrest. This isn't reflected in the description currently. [[Special:Contributions/172.70.126.121|172.70.126.121]] 16:51, 25 April 2025 (UTC)

The video URL is '''https://www.youtube.com/watch?v=JyypeEEOklM''' and appears to be "'''CBS Boston [282K subscribers]'''" so probably legit?
I will try to add the URL. --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 17:08, 25 April 2025 (UTC)
:For the sake of consistency, I copy-pasted the "note" from [[1723]] into this comic. '''I also think we should have a category and perhaps a template to make adding notes like this easier and more uniform.''' [[Special:Contributions/172.69.67.22|172.69.67.22]] 21:11, 25 April 2025 (UTC)
::Well, you can create it right now if you want! --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 22:08, 25 April 2025 (UTC)

Is this the first with an out of site link? {{unsigned}}
:No this happens often. For instance this comic {{xkcd|1723}}. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 20:09, 25 April 2025 (UTC)

Again, let's keep the explanation as neutral as possible. Facts only. [[User:Dogman15|Dogman15]] ([[User talk:Dogman15|talk]]) 18:49, 25 April 2025 (UTC)
:Dunlap's Laws. 1. Fact is solidified opinion. 2. Facts may weaken under extreme heat and pressure. 3. Truth is elastic. (Arthur Block's "Murphy's Laws", 1977.) - "Facts are elite, facts are fungible, facts are false. And once nothing is true, anything can be true." Alan Burdick, ''Trump vs Science'', New York ''Times'' Newsletter, 25 April 2025. [[Special:Contributions/172.68.22.41|172.68.22.41]] 02:10, 26 April 2025 (UTC)
: the problem is facts have a heavy anti trump bias. You CAN NOT state basic facts and not be against this regime [[Special:Contributions/162.158.112.187|162.158.112.187]] 00:05, 26 April 2025 (UTC)
:: I think it's important to emphasize that neutrality is simply a bias towards the truth rather than towards anything else. On a technical level, being unbiased precludes being neutral and being neutral precludes being unbiased, even if people mostly use the word "unbiased" in the same way as "neutral". In other words, bias isn't inherently a bad thing.[[Special:Contributions/172.71.102.219|172.71.102.219]] 00:48, 26 April 2025 (UTC)

Of course, the bit I was correcting (with bad grammar, and lack of facts) got totally changed about before I tried to post it. "''For instance citizens usually {{w|Deportation of Americans from the United States|cannot be deported for any reason}} (only extradited, although the US typically refuses to comply with requests even from countries that freely extradite to it), and would instead be subject only to local legal penalties, but relatively minor allegations have resulted in visitors' extraditions.''" was what I wrote. Now, I ''think'' that was neutral enough, but it doesn't fit there now anyway. [[Special:Contributions/172.70.58.113|172.70.58.113]] 22:45, 25 April 2025 (UTC)

:Ack, I think I'm the one who changed it before you could. My bad. Anyway, seconded. Opinion on the conflict in Gaza itself is not needed in this explanation; the edit that suggested that the student could be materially linked to Hamas by providing a link to an opinion poll of how Palestinians feel about the Oct 7 attacks is, in my opinion, very disingenuous, especially considering Ozturk is not Palestinian but Turkish, making the cited data even more blatantly irrelevant than it already would have been. [[User:Psycherprince|Psycherprince]] ([[User talk:Psycherprince|talk]]) 23:05, 25 April 2025 (UTC)

This article could potentially be a reasonable place to try to establish a norm of separately including opposing sides of political topics (rather than the usual edit conflicts). [[Special:Contributions/172.70.110.176|172.70.110.176]] 00:35, 26 April 2025 (UTC)

Step 6: Try not to lose your visa when traveling or studying abroad by being a nuisance, since visas (in any country) can be denied or revoked for virtually any reason. [[Special:Contributions/162.158.112.168|162.158.112.168]] 01:06, 26 April 2025 (UTC)
:Pray the leopards never eat your face.
::I'll bring decoy meat and try not to insult the cheetahs while visiting. [[Special:Contributions/162.158.112.186|162.158.112.186]] 01:45, 26 April 2025 (UTC)

Talk:3081: PhD Timeline

2025-04-26T02:10:26Z

172.68.22.41:

What an age we live in... --[[User:DollarStoreBa'al |DollarStoreBa'al]][[User talk:DollarStoreBa'al | Converse]][https://www.explainxkcd.com/wiki/index.php/Special:Contributions/DollarStoreBa%27al My life choices] 15:48, 25 April 2025 (UTC)
:[https://www.cnn.com/2025/04/25/politics/fbi-director-wisconsin-judge-arrested/index.html It only gets rougher... ] It's enough to radicalize a person. [[Special:Contributions/172.69.65.187|172.69.65.187]] 16:09, 25 April 2025 (UTC)
:When even Randall starts freaking out, it usually indicates the most entertaining timeline. [[Special:Contributions/162.158.245.161|162.158.245.161]] 00:58, 26 April 2025 (UTC)

Events like this are scary, and they're even scarier if you have a personal or geographic connection to them like Randall does. I can understand why he would feel frustrated about his inability to do something concrete, and if this comic raises awareness for the situation then it has done a good thing. Not sure why I thought this comment was necessary; maybe it's just a way of processing the emotions that the comic made me feel. [[User:Dextrous Fred|Dextrous Fred]] ([[User talk:Dextrous Fred|talk]]) 15:49, 25 April 2025 (UTC)

I dont want to start an argument, but I am glad Randall Munroe is making a specific, reasonable point. A lot of times I see people saying either "there is no antisemitism on campus, nobody should ever get deported, ACTUAL terrorists should get green cards", and others say "EVERYONE WHO DISAGREES WITH ME SHOULD GET DEPORTED, EVERYONE WHO DISAGREES WITH ME IS A TERRORIST." I think both of them are extreme points obviously, and I am glad Randall is just taking the side, for now, of "this specific person did not violate their green card visa."

:Hi, expert-on-the-Öztürk-case but not-an-immigration-expert-really here. For clarity, Öztürk held an F-1 student visa but was not a lawful permanent resident (LPR) (green card holder), unlike the similar case of Mahmoud Khalil (Columbia university) who was a green card holder. And "green card visa" is not a thing, there's a "green card," which you cannot "violate" (although you could commit crimes that might have consequences for your LPR status), and you generally don't hear "violate their visa" although it's true that a visa is related to and may restrict that work you can do in the country. Regardless, no allegations have been made that Öztürk violated anything laws or rules or did anything other than lend her name to speech in a newspaper. [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 22:51, 25 April 2025 (UTC)

as always, based randall, at least for now. [[User:Tzelofachad|Tzelofachad]] ([[User talk:Tzelofachad|talk]]) 16:04, 25 April 2025 (UTC)
:Did you mean "biased"? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 16:31, 25 April 2025 (UTC)
::Did you mean "biased towards due process?" [[User:CharlesT|Nyrrix]] ([[User talk:CharlesT|talk]]) 16:51, 25 April 2025 (UTC)
::It's probably "based", as that's a term that can either be used in support or mockery of a philosophical position (because of Poe's Law, hard to know which in most cases, including here). It's more usually used in 4chan-like responses (and I doubt Randall would be considered "based" in those other places) than hereabouts, so perhaps it needs some clarification for those not (or not enough) in that sort of crame of mind. [[Special:Contributions/141.101.99.94|141.101.99.94]] 17:06, 25 April 2025 (UTC)
:Yes, Randall Munroe clearly only cares about this one incident because he does not at all care about politics. He's definitely not using this as an illustrative case on the countless other identical incidents happening under the Trump administration. /s /s /s /s /s. [[User:DrMeepster|'''Dr.'''Meepster]]
(<[[User_talk:DrMeepster|chat]]> •
<[{{fullurl:{{FULLPAGENAME}}|action=edit}} reply]>) 16:53, 25 April 2025 (UTC)

I really hope this is one of those comics that does NOT stand the test of time. In other words, I hope the next generation of graduate students sees this and thinks "oh, that must've been written in 2025, we don't have to worry about those kinds of things anymore." Perhaps "hope" isn't the right word, it implies I have hope. Maybe "pray fervently" is the right phrase. Sigh. [[Special:Contributions/198.41.227.72|198.41.227.72]] 16:30, 25 April 2025 (UTC)
:Sure ... "Oh, that was before third world war, we don't have to worry about those kinds of things anymore." -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 00:08, 26 April 2025 (UTC)
:We can go back to considering how the Ph.D. became a participation trophy for the financial benefit of the awarding institution - and, in the sciences, a source of slave labor. [[Special:Contributions/172.71.146.61|172.71.146.61]] 01:51, 26 April 2025 (UTC)

How do we edit the Categories? This should have category Politics. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 16:31, 25 April 2025 (UTC)
:Usually, once at least one other category (not created from templates like {{template|comic}}) you can edit the page and see the other cat(s) at the bottom, beyond the comic-discussion template. Or edit the Transcript section (or any Trivia one, whatever's the last one) as that'll also have the tail-end of the page. So long as you know there's a category "Foo", you should be able to work out how to add "Category:Foo".
:But don't add Foo if it doesn't exist, hoping that someone will tire of the redlink that's created. You may be wrong about it needing to exist, or miss the ''actual'' "Category:comics featuring Foo", and unless someone is feeling generous it's possible that your edit just gets reverted as not properly researched, or checked... I ''think'' there actually is a Politics category, by that name, but I'm trying to answer the general question, not yet going out there to look it up for certain (at which point, I may have just added it myself, making it useless to have explained how you could 'easily' do it... At least in this instance).
:'''TL;DR;''', though, look at the source (wiki-edit) of another comic that is about Politics and is so categorised. Go all the way to bottom, and you'll see which 'tag' you might want to put at the bottom of this one. Should be obvious. [[Special:Contributions/141.101.99.94|141.101.99.94]] 17:06, 25 April 2025 (UTC)
I think I've added that category now [[Special:Contributions/104.23.190.60|104.23.190.60]] 19:33, 25 April 2025 (UTC)

I'm so tired of this administration :( [[User:CharlesT|Nyrrix]] ([[User talk:CharlesT|talk]]) 16:49, 25 April 2025 (UTC)
:Are you a citizen of the USA? If so, are you dead? In exile? In jail? Have your assets been seized? No to these? Then this is your administration and mine. Own it, or act. "Tired" doesn't cut it. [[Special:Contributions/172.71.147.21|172.71.147.21]] 02:02, 26 April 2025 (UTC)

The comic on mobile has the title text has a youtube video URL, and if you click on the comic on desktop version, it links to the youtube video of the arrest. This isn't reflected in the description currently. [[Special:Contributions/172.70.126.121|172.70.126.121]] 16:51, 25 April 2025 (UTC)

The video URL is '''https://www.youtube.com/watch?v=JyypeEEOklM''' and appears to be "'''CBS Boston [282K subscribers]'''" so probably legit?
I will try to add the URL. --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 17:08, 25 April 2025 (UTC)
:For the sake of consistency, I copy-pasted the "note" from [[1723]] into this comic. '''I also think we should have a category and perhaps a template to make adding notes like this easier and more uniform.''' [[Special:Contributions/172.69.67.22|172.69.67.22]] 21:11, 25 April 2025 (UTC)
::Well, you can create it right now if you want! --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 22:08, 25 April 2025 (UTC)

Is this the first with an out of site link? {{unsigned}}
:No this happens often. For instance this comic {{xkcd|1723}}. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 20:09, 25 April 2025 (UTC)

Again, let's keep the explanation as neutral as possible. Facts only. [[User:Dogman15|Dogman15]] ([[User talk:Dogman15|talk]]) 18:49, 25 April 2025 (UTC)
:Dunlap's Laws. 1. Fact is solidified opinion. 2. Facts may weaken under extreme heat and pressure. 3. Truth is elastic. (Arthur Block's "Murphy's Laws", 1977. - Facts are elite, facts are fungible, facts are false. And once nothing is true, anything can be true. Alan Burdick, ''Trump vs Science'', New York ''Times'' Newsletter, 25 April 2025. [[Special:Contributions/172.68.22.41|172.68.22.41]] 02:10, 26 April 2025 (UTC)
: the problem is facts have a heavy anti trump bias. You CAN NOT state basic facts and not be against this regime [[Special:Contributions/162.158.112.187|162.158.112.187]] 00:05, 26 April 2025 (UTC)
:: I think it's important to emphasize that neutrality is simply a bias towards the truth rather than towards anything else. On a technical level, being unbiased precludes being neutral and being neutral precludes being unbiased, even if people mostly use the word "unbiased" in the same way as "neutral". In other words, bias isn't inherently a bad thing.[[Special:Contributions/172.71.102.219|172.71.102.219]] 00:48, 26 April 2025 (UTC)

Of course, the bit I was correcting (with bad grammar, and lack of facts) got totally changed about before I tried to post it. "''For instance citizens usually {{w|Deportation of Americans from the United States|cannot be deported for any reason}} (only extradited, although the US typically refuses to comply with requests even from countries that freely extradite to it), and would instead be subject only to local legal penalties, but relatively minor allegations have resulted in visitors' extraditions.''" was what I wrote. Now, I ''think'' that was neutral enough, but it doesn't fit there now anyway. [[Special:Contributions/172.70.58.113|172.70.58.113]] 22:45, 25 April 2025 (UTC)

:Ack, I think I'm the one who changed it before you could. My bad. Anyway, seconded. Opinion on the conflict in Gaza itself is not needed in this explanation; the edit that suggested that the student could be materially linked to Hamas by providing a link to an opinion poll of how Palestinians feel about the Oct 7 attacks is, in my opinion, very disingenuous, especially considering Ozturk is not Palestinian but Turkish, making the cited data even more blatantly irrelevant than it already would have been. [[User:Psycherprince|Psycherprince]] ([[User talk:Psycherprince|talk]]) 23:05, 25 April 2025 (UTC)

This article could potentially be a reasonable place to try to establish a norm of separately including opposing sides of political topics (rather than the usual edit conflicts). [[Special:Contributions/172.70.110.176|172.70.110.176]] 00:35, 26 April 2025 (UTC)

Step 6: Try not to lose your visa when traveling or studying abroad by being a nuisance, since visas (in any country) can be denied or revoked for virtually any reason. [[Special:Contributions/162.158.112.168|162.158.112.168]] 01:06, 26 April 2025 (UTC)
:Pray the leopards never eat your face.
::I'll bring decoy meat and try not to insult the cheetahs while visiting. [[Special:Contributions/162.158.112.186|162.158.112.186]] 01:45, 26 April 2025 (UTC)

Talk:3078: Anchor Bolts

2025-04-21T14:32:23Z

172.68.22.41:

As a kid, I was ALWAYS worried about how plate tectonics would change the continent's layout in a few hundred million years' time, along with how the Sun will die (and maybe consume the Earth if we don't move it) in five billion years. Young me would be SO glad we are finally fixing the first issue. [[User:MinersHavenM43|MinersHavenM43]] ([[User talk:MinersHavenM43|talk]]) 03:28, 19 April 2025 (UTC)
: Was young you a Superman fan, and did you ever wonder what really happened on Krypton? Scientists and engineers, funded and enabled by a Trump-style politician and his promise to "Stop The Earthquakes NOW!", actually overcame (temporarily) the materials issues and solved the stress equations (see below), and installed a (temporarily) successful planetary plate-anchoring system. Jor-El objected to the project, he and any who supported him were de-funded as a result, and he spent his remaining time ensuring that he could get his son the [deleted] outa there before the accumulated strain ruptured the anchors and blew the planet apart. [[Special:Contributions/162.158.41.45|162.158.41.45]] 04:09, 19 April 2025 (UTC)
:Did you also worried about the collision with Andromeda galaxy? -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 05:15, 19 April 2025 (UTC)
::I was more sad that I wouldn't be able to see it within my lifetime :( [[User:MinersHavenM43|MinersHavenM43]] ([[User talk:MinersHavenM43|talk]]) 21:02, 19 April 2025 (UTC)

Would an anti-subduction screw really work? The tectonic plates are slow, but they are quite heavy, so they have a fair bit of momentum. Indeed, enough to overcome the not inconsiderable friction already present due to the weight of the uplifted portion of the upper plate. Such a screw would therefore need to exert quite a bit of additional pressure to bring the motion to a halt; Exactly how much I shall leave as an exercise for the reader (because I have no clue where to even start trying to work it out), but my guess is that you're gonna need some seriously high tensile strength material for these, even if they are placed at very short intervals along the plate boundary. [[Special:Contributions/172.68.84.172|172.68.84.172]] 03:52, 19 April 2025 (UTC)

:The screw material could easily be some sort of unobtanium, it would still not work. With the forces involved, the result would be the stone would break around the screws, IMHO. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 05:16, 19 April 2025 (UTC)

Looks like somebody got to Randall M. and pointed out that what he drew is a {{w|Bolt_(fastener)|bolt}}, not a screw. The title and caption of the comic have been edited accordingly. [[Special:Contributions/162.158.41.3|162.158.41.3]] 05:38, 19 April 2025 (UTC)

:The item depicted is a 'machine screw'; A bolt has a portion of the shaft un-threaded. An actual bolt would likely be more suitable for this application, but it's not uncommon for machine screws to be used instead.[[Special:Contributions/172.69.23.21|172.69.23.21]] 09:21, 19 April 2025 (UTC)

::This appears to be incorrect, as least in the USNA (United States in North America), fans of spurious renaming of political geography. "The [https://www.dude-n-dude.com/2025/03/16/amoebas-lorica-meme-ories-59-shame-no-2/ [sigh]] American Society of Mechanical Engineers (ASME) defines machine screws as featuring a diameter of up to 0.75 inches. While machine-screw diameters can be smaller than this, they can't be any larger, which means machine screws are typically smaller than most other screws." "Machine screws are used with a threaded hole to join two components together, sometimes requiring a nut. Bolts rely on nuts and are fitted through a clearance hole to secure parts together." [https://www.essentracomponents.com/en-us/news/solutions/fastening-components/a-guide-to-machine-screws On this evidence], the illustrated fastener is a bolt. [[Special:Contributions/172.71.142.16|172.71.142.16]] 14:34, 19 April 2025 (UTC)

:::It's hard to be pedantic about this, because nobody agrees on the distinction between a screw a bolt.[[Special:Contributions/172.68.245.131|172.68.245.131]] 13:24, 21 April 2025 (UTC)

::::Kinda figures. 'Cause, it seems, no matter how we try, or don't try, to make this bolt fit, we're screwed. [Runs.] [[Special:Contributions/172.71.147.211|172.71.147.211]] 14:20, 21 April 2025 (UTC)

This is silly. The global cooperation and engineering required to make this work (I'm assuming unobtanium as a given) far surpasses that required to decarbonise commerce and fix climate change, which project is not going well, to say the least. [[User:Neil UK|Neil UK]] ([[User talk:Neil UK|talk]]) 08:32, 19 April 2025 (UTC)
:I love how we'll give the narrative enough suspension of disbelief to allow for the bolognium we'd need to make this physically work, but actual humans, working together on a global scale project? That's way too unbelievable.[[Special:Contributions/172.70.126.168|172.70.126.168]] 22:19, 20 April 2025 (UTC)
::Yes, but that's the entire reason it's funny. [[User:Log of n|Log of n]] ([[User talk:Log of n|talk]]) 12:03, 21 April 2025 (UTC)

Added an Actual Citation Needed to vulcanism being bad for humanity. Without it, life may not have started in the first place. And fertile volcanic soils would not have sustained us/our predecessors if such life had started. Minor issues like localised danger are surely a blip in time compared to that, and even now there's only a danger to ''some'' humans (less than, say, yellowstone erupting, which isn't something a bolt could stop... in fact, drilling the bolthole sounds like it could ''cause'' a Yellowstone, if done wrongly (if, in fact, there is a 'right' way)). ...other than that, yeah, go ahead! [[Special:Contributions/172.70.91.181|172.70.91.181]] 09:49, 19 April 2025 (UTC)
:Sure, but that's not the right way to get that issue fixed. Feel free to rephrase it, or ask people to rephrase it for you in the incomplete tag. --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 11:21, 19 April 2025 (UTC)
::Did #2 --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 11:22, 19 April 2025 (UTC)
:::Solved the phrasing? I think I can remove the request from the Incomplete, but would want to retain the other expected bit (at least until the whole Incomplete gets removed, which would traditionally be no earlier than some time next week). Looks like there's arguments about this, though. [[Special:Contributions/172.70.58.97|172.70.58.97]] 14:20, 19 April 2025 (UTC)

To avoid having to travel through the mantle to insert the bolt from the bottom, wouldn't it be better to use something like a spring toggle bolt in this case? Seems like sort of a drywall situation to me. [[Special:Contributions/172.69.58.9|172.69.58.9]] 14:22, 19 April 2025 (UTC)
:Or a molly-bolt (which is dangerously close to using a {{w|wall plug}}/rawlplug ''with a screw''... as originally alluded). [[Special:Contributions/172.70.58.156|172.70.58.156]] 14:30, 19 April 2025 (UTC)

So what would be the result of this for the oceans (and connected systems)? Assuming that the bolts worked, and that the spreading at mid-ocean ridges was halted (by the vent system installed). The sea floor would not be renewed. Sediment would accumulate on the sea floor, and not be swepet under the rug. What would the long term consequences be? Would we have shallower oceans with less rocky bottoms? What would that do? (To currents, to climate, to marine life, ...) Would sedementation disrupt the circulation of ocean water through the lithosphere, messing with such things as the CO2 balance? [[Special:Contributions/108.162.246.57|108.162.246.57]] 20:35, 19 April 2025 (UTC)

Changed "crust" to "lithosphere" in a few places to avoid the popular misconception that the plates consist only of crust, rather than crust plus the upper rigid layer of mantle (upper mantle lithosphere). This misconception might be in the comic too, as the scaling of the bolted 'plates' looks more appropriate to the crust (typically ~10 km thick on the ocean side and ~35 km thick in a continent) rather than the real thickness of the plates of lithosphere (typically ~100 km).[[User:Waldronjwf|Waldronjwf]] ([[User talk:Waldronjwf|talk]]) 16:40, 20 April 2025 (UTC)

It's odd to me that the discussion of anchor bolts talks about holding buildings to foundations, and furniture to the floor, but not the geotechnical engineering application to prevent falling rocks/erosion. An anchor bolt in that case is generally cemented into a hole in the rock, and then tensioned against the face of the hill/cliff to stabilize it.[[Special:Contributions/172.70.38.246|172.70.38.246]] 13:36, 21 April 2025 (UTC)

:And all the state's boltings, and all the state's men,/Couldn't put {{w|Old_Man_of_the_Mountain#Collapse|Humpty together again}}. Vanity of vanities ... [[Special:Contributions/172.68.22.41|172.68.22.41]] 14:32, 21 April 2025 (UTC)

3078: Anchor Bolts

2025-04-19T20:19:32Z

172.68.22.41: /* Explanation */ wikilinks

{{comic
| number = 3078
| date = April 18, 2025
| title = Anchor Bolts
| image = anchor_screws_2x.png
| imagesize = 381x326px
| noexpand = true
| titletext = The biggest expense was installing the mantle ducts to keep the carbonate-silicate cycle operating.
}}

==Explanation==
{{incomplete|Created by an AUTOMATIC SUBLIMATOR. Don't remove this notice too soon. Need to rephrase a section, see the talk page.}}

The comic displays a cross-section of a subduction zone. {{w|Subduction}} is a geologic process in which two {{w|Plate tectonics|plates}} of planetary crust collide, and one is dragged under the other. The Earth's crust is divided into tectonic plates. They slowly move across the surface at a few centimeters per year, although the rate is nonuniform across plates. Sometimes, when they collide, the denser plate gets dragged under the less dense plate, in a process called subduction. {{w|Earthquake|Earthquakes}} are common at subduction zones, and subduction can also lead to volcanic activity. An "anti-subduction anchor bolt" would effectively stop the process of subduction and the movement of plate tectonics as a whole.{{citation needed}}

A round head bolt is screwed in through both the oceanic lithosphere and the continental crust from the bottom up, with a plain washer on either side, and a wing nut tightened at the surface. Washers are present to prevent the bolt and the wing nut from sinking into the crust, by distributing the forces over larger areas. There are several concerns not addressed in the comic with such a design. The implication that the bolt is being screwed in from the mantle side would imply that a very large bolt head was operated from inside the mantle. (There are nut-and-bolt-type systems that might be easier to deploy, such as {{w|toggle bolt}}s and {{w|Molly (fastener)|mollys}}. These would have the bolt head on the Earth's surface, rather than in the mantle, and use a spreading "nut" inside the Earth. They wouldn't require conducting enormous operations from below, "merely" a large hole bored from above.) As of the time of posting of the comic, humans have not drilled a hole through a continental crust, still less deployed large vehicles in the mantle. In addition, the presence of wing nuts, fasteners that are designed to be able to be screwed in by hand, implies work done by a larger being that has appendages able to use the wing nut. The bolt itself would be a technological challenge, as well. It would need to be made to withstand the temperature of Earth's mantle, around 1000°C near the surface. At these temperatures, most commercial stainless steel used to manufacture bolts would experience noticeable strength losses. The bolt would need be around 50 km long. Moreover, as subduction zones move parallel to each other, the construction would have to withstand high shear forces, something that a bolt is rather unsuited to compared to other tools, such as rivets. On top of that, ways to alleviate stress must be sought out as if the bolt fails, it could produce a highly amplified earthquake.

In the short term, earthquakes and volcanic eruptions are typically bad for those living nearby, and thus ways to prevent them happening might reduce economic risks in those areas. Volcanic eruptions deposit nutrients in the surrounding area, making rich soils. Volcanos also release gasses. The vents mentioned in the title text might replenish the nutrients and gasses, replacing the benefits of eruptions. Earthquakes sometimes trigger {{w|tsunami|tsunamis}}, which create or modify beaches, and redistribute nutrients from bays and estuaries across coastal plains. So, while the immediate effects of eruptions and earth quakes can be disruptive, they also enrich the environment. Areas at risk from these "disasters" are also attractive as a result of these same events.

When plates collide but do not subduct, they often uplift, thickening or raising the crust. The {{w|Himalayas|Himalaya}} mountains, are an example. Tectonic plates spread apart as new crust is deposited at ridges, most of which occur under oceans. If spreading continued, but subduction was prevented by the system of anchors pictured in this cartoon, there would likely be new areas of uplift. If positioned appropriately, the mantle ducts, mentioned in the title text, might slow or stop the spreading, reducing uplift.

The title text references the {{w|Carbonate–silicate cycle|carbonate-silicate geochemical cycle}}. Briefly, subduction and subsequent heating of the global crust restores carbon dioxide and silicate rocks to the planetary surface, countering the effects of carbonate deposition and silicate rock weathering. Anchor bolts sufficient to stop plate tectonics would also stop the carbonate-silicate cycle, leading to unexpected, and likely unwelcome, changes in the surface geosphere and biosphere. (Arguably, if the carbonate cycle alone could be paused, it might be a means of reducing the amount of carbon dioxide in the biosphere.) To restore the cycle by an unknown mechanism, "mantle ducts" have been installed as part of the planet-wide plate anchoring system. It is stated that the mantle duct installation was the most expensive part of the project, implying greater intellectual and technical challenges than the already-massive ones associated with anchor-bolt design and deployment.

This project would presumably render [[Beret Guy]]'s [[1388|Subduction License]] worthless.

==Transcript==
:[Panel shows Randall's usual illustration of a subduction zone: a tectonic plate subducting from the left side of the panel with water above it, and a mountain range forming on the right side of the panel on the other tectonic plate. Beneath each tectonic plate is the asthenosphere. The main difference between this image and others like it is that there is a bolt shown attaching the plates together in the subduction zone. The head of the bolt is shown in the asthenosphere below the subducting plate. There are two washers displayed, one between the bolt head and the subducting plate and one above the other above the upper plate on the side of a smaller mountain. A wing nut is positioned above this washer, with part of the bolt sticking out above the nut, higher than the tallest mountains in the panel]

:[Caption below the panel:]
:Good news: Geophysicists are '''''finally''''' installing Earth's required anti-subduction anchor bolts.

==Trivia==
In the [https://www.explainxkcd.com/wiki/images/archive/0/00/20250419063115%21anchor_screws_2x.png original version of the comic], the caption said "anti-subduction anchor '''screws'''" instead of "anti-subduction anchor '''bolts'''". The title of the comic was also changed, from "Anchor Screws" to "Anchor Bolts". The original comic image and title can be seen on an [https://web.archive.org/web/20250419024242/https://xkcd.com/3078/ archived version] of the [https://xkcd.com xkcd.com] site. The fastener illustrated is indeed a {{w|Bolt (fastener)|bolt}} (with a {{w|Wingnut (hardware)|wing nut}}), not a screw. A screw has a pointed end and is drilled into a hole that is smaller than the diameter of the screw; the pressure caused by its {{w|screw thread|thread}} and screw head binds two objects together. A screw does not need a nut to go with it.

A bolt has a flat end, and it goes into a hole that is larger than the diameter of the bolt; it needs a nut which, when fixed onto the bolt and tightened, together with the head creates the pressure that binds the two objects together. Because a nut is used to create pressure, "bolt" is a more correct term than "screw", although it is very common to talk of 'screws' for [[1474: Screws|screw-headed]] bolts which attach panels (with non-threaded holes) against a substrate which which incorporates a 'nut-like' threaded hole within it (or a nut encapsulated and held non-rotating in the backing plate's recess), even though they are also flat-faced at the thread-end and not self-tapping.

Or, for a differently worded definition, {{w|Screw#Differentiation between bolt and screw|see here}}.

{{comic discussion}}

[[Category:Subduction]]
[[Category:Geology]]
[[Category:Comics edited after their publication]]

3078: Anchor Bolts

2025-04-19T20:07:33Z

172.68.22.41: /* Explanation */ volcanic eruptions and tsunami make really rich/attractive places

{{comic
| number = 3078
| date = April 18, 2025
| title = Anchor Bolts
| image = anchor_screws_2x.png
| imagesize = 381x326px
| noexpand = true
| titletext = The biggest expense was installing the mantle ducts to keep the carbonate-silicate cycle operating.
}}

==Explanation==
{{incomplete|Created by an AUTOMATIC SUBLIMATOR. Don't remove this notice too soon. Need to rephrase a section, see the talk page.}}

The comic displays a cross-section of a subduction zone. Subduction is a geologic process in which two plates of planetary crust collide, and one is dragged under the other. The Earth's crust is divided into tectonic plates. They slowly move across the surface at a few centimeters per year, although the rate is nonuniform across plates. Sometimes, when they collide, the denser plate gets dragged under the less dense plate, in a process called subduction. Earthquakes are common at subduction zones, and subduction can also lead to volcanic activity. In the short term, earthquakes and volcanic eruptions are typically bad for those living nearby, and thus ways to prevent them happening might reduce economic risks in those areas. An "anti-subduction anchor bolt" would effectively stop the process of subduction and the movement of plate tectonics as a whole.{{citation needed}}

A round head bolt is screwed in through both the oceanic lithosphere and the continental crust from the bottom up, with a plain washer on either side, and a wing nut tightened at the surface. Washers are present to prevent the bolt and the wing nut from sinking into the crust, by distributing the forces over larger areas. There are several concerns not addressed in the comic with such a design. The implication that the bolt is being screwed in from the mantle side would imply that a very large bolt head was operated from inside the mantle. (There are nut-and-bolt-type systems that might be easier to deploy, such as {{w|toggle bolt}}s and {{w|Molly (fastener)|mollys}}. These would have the bolt head on the Earth's surface, rather than in the mantle, and use a spreading "nut" inside the Earth. They wouldn't require conducting enormous operations from below, "merely" a large hole bored from above.) As of the time of posting of the comic, humans have not drilled a hole through a continental crust, still less deployed large vehicles in the mantle. In addition, the presence of wing nuts, fasteners that are designed to be able to be screwed in by hand, implies work done by a larger being that has appendages able to use the wing nut. The bolt itself would be a technological challenge, as well. It would need to be made to withstand the temperature of Earth's mantle, around 1000°C near the surface. At these temperatures, most commercial stainless steel used to manufacture bolts would experience noticeable strength losses. The bolt would need be around 50 km long. Moreover, as subduction zones move parallel to each other, the construction would have to withstand high shear forces, something that a bolt is rather unsuited to compared to other tools, such as rivets. On top of that, ways to alleviate stress must be sought out as if the bolt fails, it could produce a highly amplified earthquake.

Volcanic eruptions deposit nutrients in the surrounding area, making rich soils. They also release gasses. Earthquakes sometimes trigger {{w|tsunami|tsunamis}}, which create or modify beaches, and redistribute nutrients from bays and estuaries across coastal plains. The vents mentioned in the title text might replenish the nutrients and gasses. So, while the immediate effects of eruptions and earth quakes can be disruptive, they also enrich the environment. Areas at risk from these "disasters" are also attractive as a result.

When plates collide but do not subduct, they often uplift, thickening or raising the crust. The Himmalaya mountains, are an example. Tectonic plates spread apart as new crust is deposited at ridges, most of which occur under oceans. If spreading continued, but subduction was prevented by the system of anchors pictured in this cartoon, there would likely be new areas of uplift. If positioned appropriately, the mantle ducts, mentioned in the title text, might slow or stop the spreading, reducing uplift.

The title text references the {{w|Carbonate–silicate cycle|carbonate-silicate geochemical cycle}}. Briefly, subduction and subsequent heating of the global crust restores carbon dioxide and silicate rocks to the planetary surface, countering the effects of carbonate deposition and silicate rock weathering. Anchor bolts sufficient to stop plate tectonics would also stop the carbonate-silicate cycle, leading to unexpected, and likely unwelcome, changes in the surface geosphere and biosphere. (Arguably, if the carbonate cycle alone could be paused, it might be a means of reducing the amount of carbon dioxide in the biosphere.) To restore the cycle by an unknown mechanism, "mantle ducts" have been installed as part of the planet-wide plate anchoring system. It is stated that the mantle duct installation was the most expensive part of the project, implying greater intellectual and technical challenges than the already-massive ones associated with anchor-bolt design and deployment.

This project would presumably render [[Beret Guy]]'s [[1388|Subduction License]] worthless.

==Transcript==
:[Panel shows Randall's usual illustration of a subduction zone: a tectonic plate subducting from the left side of the panel with water above it, and a mountain range forming on the right side of the panel on the other tectonic plate. Beneath each tectonic plate is the asthenosphere. The main difference between this image and others like it is that there is a bolt shown attaching the plates together in the subduction zone. The head of the bolt is shown in the asthenosphere below the subducting plate. There are two washers displayed, one between the bolt head and the subducting plate and one above the other above the upper plate on the side of a smaller mountain. A wing nut is positioned above this washer, with part of the bolt sticking out above the nut, higher than the tallest mountains in the panel]

:[Caption below the panel:]
:Good news: Geophysicists are '''''finally''''' installing Earth's required anti-subduction anchor bolts.

==Trivia==
In the [https://www.explainxkcd.com/wiki/images/archive/0/00/20250419063115%21anchor_screws_2x.png original version of the comic], the caption said "anti-subduction anchor '''screws'''" instead of "anti-subduction anchor '''bolts'''". The title of the comic was also changed, from "Anchor Screws" to "Anchor Bolts". The original comic image and title can be seen on an [https://web.archive.org/web/20250419024242/https://xkcd.com/3078/ archived version] of the [https://xkcd.com xkcd.com] site. The fastener illustrated is indeed a {{w|Bolt (fastener)|bolt}} (with a {{w|Wingnut (hardware)|wing nut}}), not a screw. A screw has a pointed end and is drilled into a hole that is smaller than the diameter of the screw; the pressure caused by its {{w|screw thread|thread}} and screw head binds two objects together. A screw does not need a nut to go with it.

A bolt has a flat end, and it goes into a hole that is larger than the diameter of the bolt; it needs a nut which, when fixed onto the bolt and tightened, together with the head creates the pressure that binds the two objects together. Because a nut is used to create pressure, "bolt" is a more correct term than "screw", although it is very common to talk of 'screws' for [[1474: Screws|screw-headed]] bolts which attach panels (with non-threaded holes) against a substrate which which incorporates a 'nut-like' threaded hole within it (or a nut encapsulated and held non-rotating in the backing plate's recess), even though they are also flat-faced at the thread-end and not self-tapping.

Or, for a differently worded definition, {{w|Screw#Differentiation between bolt and screw|see here}}.

{{comic discussion}}

[[Category:Subduction]]
[[Category:Geology]]
[[Category:Comics edited after their publication]]

3078: Anchor Bolts

2025-04-19T19:53:10Z

172.68.22.41: /* Explanation */ add uplift - if spreading continues but plates all locked, surface would crinkle up

{{comic
| number = 3078
| date = April 18, 2025
| title = Anchor Bolts
| image = anchor_screws_2x.png
| imagesize = 381x326px
| noexpand = true
| titletext = The biggest expense was installing the mantle ducts to keep the carbonate-silicate cycle operating.
}}

==Explanation==
{{incomplete|Created by an AUTOMATIC SUBLIMATOR. Don't remove this notice too soon. Need to rephrase a section, see the talk page.}}

The comic displays a cross-section of a subduction zone. Subduction is a geologic process in which two plates of planetary crust collide, and one is dragged under the other. The Earth's crust is divided into tectonic plates. They slowly move across the surface at a few centimeters per year, although the rate is nonuniform across plates. Sometimes, when they collide, the denser plate gets dragged under the less dense plate, in a process called subduction. Earthquakes are common at subduction zones, and subduction can also lead to volcanic activity. In the short term, earthquakes and volcanic eruptions are typically bad for those living nearby, and thus ways to prevent them happening might reduce economic risks in those areas. An "anti-subduction anchor bolt" would effectively stop the process of subduction and the movement of plate tectonics as a whole.{{citation needed}}

A round head bolt is screwed in through both the oceanic lithosphere and the continental crust from the bottom up, with a plain washer on either side, and a wing nut tightened at the surface. Washers are present to prevent the bolt and the wing nut from sinking into the crust, by distributing the forces over larger areas. There are several concerns not addressed in the comic with such a design. The implication that the bolt is being screwed in from the mantle side would imply that a very large bolt head was operated from inside the mantle. (There are nut-and-bolt-type systems that might be easier to deploy, such as {{w|toggle bolt}}s and {{w|Molly (fastener)|mollys}}. These would have the bolt head on the Earth's surface, rather than in the mantle, and use a spreading "nut" inside the Earth. They wouldn't require conducting enormous operations from below, "merely" a large hole bored from above.) As of the time of posting of the comic, humans have not drilled a hole through a continental crust, still less deployed large vehicles in the mantle. In addition, the presence of wing nuts, fasteners that are designed to be able to be screwed in by hand, implies work done by a larger being that has appendages able to use the wing nut. The bolt itself would be a technological challenge, as well. It would need to be made to withstand the temperature of Earth's mantle, around 1000°C near the surface. At these temperatures, most commercial stainless steel used to manufacture bolts would experience noticeable strength losses. The bolt would need be around 50 km long. Moreover, as subduction zones move parallel to each other, the construction would have to withstand high shear forces, something that a bolt is rather unsuited to compared to other tools, such as rivets. On top of that, ways to alleviate stress must be sought out as if the bolt fails, it could produce a highly amplified earthquake.

When plates collide but do not subduct, they often uplift, thickening or raising the crust. The Himmalaya mountains, are an example. Tectonic plates spread apart as new crust is deposited at ridges, most of which occur under oceans. If spreading continued, but subduction was prevented by the system of anchors pictured in this cartoon, there would likely be new areas of uplift. If positioned appropriately, the mantle ducts, mentioned in the title text, might slow or stop the spreading, reducing uplift.

The title text references the {{w|Carbonate–silicate cycle|carbonate-silicate geochemical cycle}}. Briefly, subduction and subsequent heating of the global crust restores carbon dioxide and silicate rocks to the planetary surface, countering the effects of carbonate deposition and silicate rock weathering. Anchor bolts sufficient to stop plate tectonics would also stop the carbonate-silicate cycle, leading to unexpected, and likely unwelcome, changes in the surface geosphere and biosphere. (Arguably, if the carbonate cycle alone could be paused, it might be a means of reducing the amount of carbon dioxide in the biosphere.) To restore the cycle by an unknown mechanism, "mantle ducts" have been installed as part of the planet-wide plate anchoring system. It is stated that the mantle duct installation was the most expensive part of the project, implying greater intellectual and technical challenges than the already-massive ones associated with anchor-bolt design and deployment.

This project would presumably render [[Beret Guy]]'s [[1388|Subduction License]] worthless.

==Transcript==
:[Panel shows Randall's usual illustration of a subduction zone: a tectonic plate subducting from the left side of the panel with water above it, and a mountain range forming on the right side of the panel on the other tectonic plate. Beneath each tectonic plate is the asthenosphere. The main difference between this image and others like it is that there is a bolt shown attaching the plates together in the subduction zone. The head of the bolt is shown in the asthenosphere below the subducting plate. There are two washers displayed, one between the bolt head and the subducting plate and one above the other above the upper plate on the side of a smaller mountain. A wing nut is positioned above this washer, with part of the bolt sticking out above the nut, higher than the tallest mountains in the panel]

:[Caption below the panel:]
:Good news: Geophysicists are '''''finally''''' installing Earth's required anti-subduction anchor bolts.

==Trivia==
In the [https://www.explainxkcd.com/wiki/images/archive/0/00/20250419063115%21anchor_screws_2x.png original version of the comic], the caption said "anti-subduction anchor '''screws'''" instead of "anti-subduction anchor '''bolts'''". The title of the comic was also changed, from "Anchor Screws" to "Anchor Bolts". The original comic image and title can be seen on an [https://web.archive.org/web/20250419024242/https://xkcd.com/3078/ archived version] of the [https://xkcd.com xkcd.com] site. The fastener illustrated is indeed a {{w|Bolt (fastener)|bolt}} (with a {{w|Wingnut (hardware)|wing nut}}), not a screw. A screw has a pointed end and is drilled into a hole that is smaller than the diameter of the screw; the pressure caused by its {{w|screw thread|thread}} and screw head binds two objects together. A screw does not need a nut to go with it.

A bolt has a flat end, and it goes into a hole that is larger than the diameter of the bolt; it needs a nut which, when fixed onto the bolt and tightened, together with the head creates the pressure that binds the two objects together. Because a nut is used to create pressure, "bolt" is a more correct term than "screw", although it is very common to talk of 'screws' for [[1474: Screws|screw-headed]] bolts which attach panels (with non-threaded holes) against a substrate which which incorporates a 'nut-like' threaded hole within it (or a nut encapsulated and held non-rotating in the backing plate's recess), even though they are also flat-faced at the thread-end and not self-tapping.

Or, for a differently worded definition, {{w|Screw#Differentiation between bolt and screw|see here}}.

{{comic discussion}}

[[Category:Subduction]]
[[Category:Geology]]
[[Category:Comics edited after their publication]]

Talk:unixkcd

2025-04-16T05:07:45Z

172.68.22.41:

Red link... — [[User:Sqrt-1|The 𝗦𝗾𝗿𝘁-𝟭]] [[User talk:Sqrt-1|talk]] [[Special:Contributions/Sqrt-1|stalk]] 10:45, 11 October 2020 (UTC)

has skmone made an actual CLI based on these commands? [[Special:Contributions/172.69.214.224|172.69.214.224]] 02:12, 22 November 2023 (UTC)

The Konami Code isn't working for me, does anyone else have this problem? [[User:Psychoticpotato|Psychoticpotato]] ([[User talk:Psychoticpotato|talk]]) 18:50, 10 May 2024 (UTC)

Should we consider this a comic? I don't know how to think about it. [[Blue Eyes]] wasn't a comic but we still consider it as one. --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 09:31, 22 February 2025 (UTC)

The moo still works after sudo rm -rf / (--no-preserve-root)

3076: The Roads Both Taken

2025-04-15T18:32:08Z

172.68.22.41:

{{comic
| number = 3076
| date = April 14, 2025
| title = The Roads Both Taken
| image = the_roads_both_taken_2x.png
| imagesize = 361x362px
| noexpand = true
| titletext = When you worry that you're missing out on something by not making both choices simultaneously by quantum superposition, that's called phomo.
}}

==Explanation==
{{incomplete|Simultaneously created by and not created by SCHRÖDINGER'S LYRICIST - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic is a parody of the first and fourth stanzas of {{w|Robert Frost}}'s 1915 poem "{{w|The Road Not Taken}}". The joke is that, while the human narrator of Frost's poem (presumably Frost himself), confronted with two paths, could only take one of them, and is left to [[584: Unsatisfied|contemplate the consequences of his choice]], the photonic narrator of the parody, thanks to {{w|Quantum superposition|quantum physics}}, is not compelled to choose one path over the other, and is left to contemplate the {{w|Wave interference#Quantum interference|consequences of that choice}}.

The title text humorously conflates FOMO (Fear Of Missing Out), the human concern over lost opportunities from choosing one path over another (or choosing neither) with PHOMO (presumably PHOton Missing Out), the photonic concern over lost opportunities from choosing both paths at once, instead of one only, or none.

This comic was posted on April 14, [https://www.quantum.gov/happy-world-quantum-day-2025 World Quantum Day].

{| class="wikitable"
!Original stanza
!Parody
!Explanation
|-
|Two roads diverged in a yellow wood, And ''sorry I could not travel'' both ''And'' be one traveler, ''long I stood'' ''And looked down one'' as far as I could ''To where it bent'' in the undergrowth;
|Two roads diverged in a yellow wood, And ''so of course I traveled'' both ''Though'' be one traveler, ''still I could'' ''Explore down both'' as far as I could ''Beyond the bends'' in the undergrowth;
|In the original, the human narrator, operating at the scale of classical mechanics, contemplates the necessary choice between two mutually exclusive paths. In the parody, the photon, operating at the scale of quantum mechanics, readily explores both paths. At quantum scale, the "roads" and "yellow woods" are metaphorical.
|-
|I shall be telling this with a sigh Somewhere ages and ages hence: Two roads diverged in a wood, and I— I took ''the one less travelled by,'' And that has made ''all the difference.''
|I shall be telling this with a sigh Somewhere ages and ages hence: Two roads diverged in a wood, and I, I took ''them both and recombined,'' And that has made ''interference.''
|
|}

The parody maintains the same rhyme scheme as the original, ABAAB. In the fourth line of the last stanza. "recombined" doesn't {{w|Perfect_and_imperfect_rhymes|perfectly}} rhyme with "sigh" and "I", but it shares the vowel in the last syllable, a form of {{w|assonance}}, and can be considered an {{w|Perfect_and_imperfect_rhymes#Imperfect_rhyme|imperfect rhyme}}.

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

:[A photon recites a poem:]
:Two roads diverged in a yellow wood,
:And so of course I traveled both
:Though be one traveler, still I could
:Explore down both as far as I could
:Beyond the bends in the undergrowth...

:...I shall be telling this with a sigh
:Somewhere ages and ages hence:
:Two roads diverged in a wood, and I,
:I took them both and recombined,
:And that has made interference.

:[Caption below the panel:]
:Photon poetry

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

3073: Tariffs

2025-04-10T05:30:17Z

172.68.22.41: /* Explanation */ remove excess words

{{comic
| number = 3073
| date = April 7, 2025
| title = Tariffs
| image = tariffs_2x.png
| imagesize = 681x809px
| noexpand = true
| titletext = [later] I don't get why our pizza slices have such terrible reviews; the geotextile-infused sauce gives the toppings incredible slope stability!
}}

==Explanation==

{{notice|This comic and explanation is about present-day politics and {{w|Donald Trump|Donald Trump, the current President of the United States}}. Additionally, the comic is about a political policy point that has disparate viewpoints which are both backed by extensive study and rarely implemented well. Please {{w|WP:DFTT|don’t feed the trolls}}, meaning that you don’t give recognition or respond to trolls or vandals. If you find vandalism, revert and move on. If the vandal is a registered user, {{w|WP:RBI|revert, block and ignore}}. If you are not an admin and need assistance in blocking someone, send a message to [[User:Kynde]] or [[User:Theusaf]]. As with these contentious topics, please do not edit if you believe you have a conflict of interest or might be writing in a biased and slanted manner (in regards to both major American political parties). Be {{w|WP:BOLD|bold}}, but not reckless. Always be considerate of the other side, don’t {{w|WP:CIVIL|attack people}}, and always {{w|WP:AGF|assume good faith}}. Thanks, '''[[User:42.book.addict|42.book.addict]][[User talk:42.book.addict|Talk to me!]]''' 00:23, 9 April 2025 (UTC)}}

{{incomplete|Created by a SPOILER FOR AVATAR 2 (Rosebud is his Ikran) - Please change this comment when editing this page. Explanation of the consequences of stopping imports (the last panel) is needed. Do NOT delete this tag too soon.}}

This comic is a parody of the tariffs that US president {{w|Donald Trump}} {{w|tariffs in the second Trump administration|imposed in April 2025}}, which were announced shortly before the comic's release. [[Cueball]] describes the tariffs to [[Ponytail]]. Cueball uses a pizza analogy to describe why the plan has garnered widespread disapproval for several seemingly illogical decisions.

In early 2021 ponytail blocked news sites to avoid {{w|spoiler (media)|spoiler}}s about ''Avatar 2'' (officially titled ''{{w|Avatar: The Way of Water}}''). ''Avatar 2'' was released on December 16, 2022, but she did not re-enable notifications until April 2025. This means that she has missed all news since 2021, including the re-election of Trump in 2024. She is surprised that Donald Trump is still the president in early 2025. She may be under the impression that Trump refused to step down when [[Joe Biden]]'s presidency officially began on Jan. 20, 2021. Trump has made repeated false claims that {{w|2020 United States presidential election#False claims of fraud| the election was "stolen"}} shortly after the 2020 elections, indicating his reluctance to accept the results. On one hand, a U.S. president serving nonconsecutive terms has only happened once before; {{w|Grover Cleveland}} served from 1885 to 1889 and again from 1893 to 1897. On the other hand, only {{w|Franklin D. Roosevelt}} ever had more than two four-year terms, and that was before the {{w|Twenty-second Amendment to the United States Constitution|22nd Amendment}} made it even less of a possibility that one could have started a third ([[2875: 2024|without getting false teeth, that is]]). Previously, in [[2396: Wonder Woman 1984]], ponytail also blocked news to avoid movie spoilers.

Ponytail has further missed Trump's wide-ranging tariffs, and the attending news coverage that has served to introduce many people to what tariffs are and how they work. Cueball attempts to explain by comparing the U.S. with the Geotechnical Survey company that Ponytail works for, as they are both producers of goods and services, and comparing the countries the U.S. imports from to a pizza place, since the U.S. primarily imports lower value consumer goods and materials used to make the goods that the U.S. then exports, similar to how pizzas feed the workers in Ponytail's company.

A trade deficit occurs when party A buys more from party B than they sell to party B. Donald Trump, the president of the United States at the time the comic released, claimed that if the U.S. has a trade deficit with another country, then the U.S. is getting ripped off and the other country must be punished.{{Actual citation needed}} In the comic, Cueball mockingly echoes Trump's belief to better explain his policies. As Ponytail explains, there is nothing wrong with having a trade deficit if you think you are getting your money's worth for what you are buying — specifically, looking purely at a "trade deficit" on paper does not tell you if the crediting partner is purchasing ''services'' from or offering other benefits to the debtor partner.

Many countries trade; a trade deficit with one country may be offset by a trade surplus with other countries. As long as countries maintain overall balance of trade, a trade deficit with one country is of little significance. The U.S. can benefit from a trade deficit in some cases: the flow of foreign capital (like factory machinery) into the country can allow for more development, and some kinds of production are dangerous or polluting relative to the value of the goods produced. In addition, up to today, the U.S. treasury commands the world's most common reserve currency, which is also the currency used for most world trade, making outflow of foreign currency not really a problem.{{Actual citation needed}}

A tariff is a tax on imports from another country. Most politicians try to balance tariffs carefully, for instance to keep domestic products competitive with imported goods. In contrast, Donald Trump introduced tariffs aggressively with the aim to "punish" countries with which the United States had a trade deficit. He claims that tariffs on goods manufactured abroad will encourage domestic manufacturing in order to avoid these tariffs, which will then provide more middle-class jobs. Many worry excessive tariffs will artificially inflate costs of products from other countries, leaving consumers with even higher prices (especially prices of goods which the United States cannot wholly produce domestically). Additionally, if other countries retaliate with tariffs (typically more well chosen ones, specifically targeting products that the U.S. wants to sell more than the other country needs to buy them) it could result in a "{{w|trade war}}".

In the comic, Cueball proposes that Ponytail impose a tax or "tariff" on the pizza store until they start buying from Ponytail's company. ({{w|Venmo}} is a payment platform; it's not like [[2716: Game Night Ordering|Yahoo Cash]] was an option anyway) Notably, the tariff is applied on the people who deliver the products to Ponytail's company, just like in real life. Ponytail notes that such a tariff might discourage pizza store from selling to her, which Cueball considers (in his position as devil's advocate for the whole concept) a victory. Nations have very little control of where the products they export go. Instead, it is left up to the companies (the delivery companies, in this case) to decide where to produce (or procure) the goods. What tariff proponents often omit, is that companies will simply pass on the costs associated with tariffs to the purchaser, making the pizza more expensive for the consumer, with no benefit to the supplier. In practical terms, the pizza company may stop taking orders from this company, having other customers that are easier to deliver to. Even if there's a saturated pizza industry, with several pizza outlets all vying for the local business, it may be easier to compete for the slightly smaller 'rest of the town' market, perhaps even to offer deliveries to places previously outside their area, than to pay the survey company.

In contrast to real world countries like China or Canada which, as of 2025, procure a substantial amount of goods from the U.S., Ponytail notes that the pizza company has little use for land survey equipment, unless they are constructing their own stores from the ground up without outside contractors. Ponytail suggests surveying pizzas using their equipment, which would serve little purpose.

The U.S. used to be a dominant producer of consumer goods up until the 1970s, after which companies started offshoring production that utilized low-skilled labor to third-world countries. In contrast, Ponytail's company likely has never been a producer of food. {{w|LIDAR}} is a technique using lasers to measure distances. Ponytail's company is using the technology to do surveying. In the final panel and title text, Cueball suggests that they use their LIDAR components to make their own pizzas, which would be inedible and potentially toxic.{{Citation needed}} Cueball may be referencing the annoyance Italians have at unconventional pizza toppings.

The title text references slope stability, or the ability of an inclined slope to withstand movement. Toppings often slide off poorly-made pizzas when it is being eaten, leading to dissatisfaction. {{w|Geotextile}}s are permeable fabrics used for support and various other functions. The narrator claims that geotextiles prevent toppings from sliding off the pizza. However, very few geotextiles are edible{{Citation needed}}, which may reference [https://www.bbc.co.uk/news/articles/cd11gzejgz4o Google's AI suggesting using non-toxic glue to ensure cheese doesn't slide off].

==Transcript==
:[Ponytail walks over to Cueball while looking at a phone in her hand. Cueball, sitting in an office chair, is leaning back on the chair and turns his head towards her. He is at his desk with his laptop open in front of him.]
:Ponytail: You know how I blocked all news sites at the start of 2021 to avoid spoilers for Avatar 2, and then forgot to start checking them again?
:Cueball: Yeah, we've been meaning to talk to you about that...

:[Ponytail, still holding the phone, stops in front of Cueball and looks at him. He has turned his chair around to face her, having his back to the desk with the laptop.]
:Ponytail: Well, I just checked the news for the first time, and why is the economy tanking?
:Cueball: Uh, the president is mad at other countries and imposed lots of tariffs.

:[Zoom in on Ponytail's head. Cueball's reply comes from a starburst on the right edge of the panel.]
:Ponytail: Wait, who's the president now?
:Cueball (off-panel): Donald Trump.
:Ponytail: ...Still??
:Cueball (off-panel): No, again.

:[Back to the previous setting, Ponytail is no longer holding the phone.]
:Ponytail: OK, fine, what's a tariff? Why is he doing this?
:Cueball: You know that pizzeria your company orders from? They don't buy anything from '''''you''''', right?
:Ponytail: Why would they? We do geotechnical landscape surveys.

:[Zoom in on Cueball who holds both his arms out wide. Ponytail's reply comes from a starburst on the left edge of the panel.]
:Cueball: Right, so they're ripping you off! '''''You're''''' paying '''''them''''' tons of money, and what are '''''you''''' getting for it?
:Ponytail (off-panel): I mean... pizza?
:Cueball: See? They're not helping '''''your''''' business at all!
:Cueball: What a ripoff!

:[Back to the previous setting, Ponytail has her hand under her chin.]
:Ponytail: What would they even buy from us? I guess we could survey a pizza...
:Cueball: Yes, perfect! You refuse to let the delivery driver past your security desk unless they Venmo you for an equivalent value of LIDAR scans.

:[Zoom in on Ponytail's head. Cueball's reply comes from a starburst on the right edge of the panel.]
:Ponytail: Wouldn't they just stop taking our orders?
:Cueball (off-panel): Perfect, balance restored!

:[Back to showing both of them in the same position but the desk is not shown.]
:Ponytail: OK, but I still want pizza.
:Cueball: Can you just make one? You have all that gear.
:Ponytail: I don't think pizza made with LIDAR diodes would be very good.
:Cueball: Ugh, why is everyone so picky about toppings?

{{comic discussion}}

[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Donald Trump]]
[[Category:Politics]]
[[Category:Food]]
[[Category:Geology]]