explain xkcd - User contributions [en]

2016: OEIS Submissions

2025-02-15T12:51:24Z

172.69.134.31: /* Explanation */

<noinclude>{{distinguish|1624: 2016}}</noinclude>
{{comic
| number = 2016
| date = July 6, 2018
| title = OEIS Submissions
| image = oeis_submissions.png
| titletext = SUB[59]: The submission numbers for my accepted OEIS submissions in chronological order
}}

==Explanation==

The {{w|OEIS}} is the [https://oeis.org/ Online Encyclopedia of Integer Sequences], a listing of hundreds of thousands of sequences of integers, generally of real mathematical interest, such as {{w|prime number}}s ([https://oeis.org/A000040 A000040]) or {{w|Armstrong number}}s ([https://oeis.org/A005188 A005188]). The OEIS normally expects submissions to be accompanied by references to scholarly articles about, or at least referencing, the sequence. They would not be interested in the personal or idiosyncratic sequences proposed by Randall, though they do have the [https://oeis.org/A000053 list of subway stops on the New York City Broadway line (IRT #1)], perhaps because a NY Times article mentioned that they don't.

Randall is trying to put his integer sequences on the OEIS website, including making OEIS reveal its password.
;sub[43] - All integers which do not appear in the example terms of another OEIS sequence
:Every OEIS sequence lists several example terms to demonstrate the content of said sequence. This request wants to list all integers which are ''not'' used as examples elsewhere. Any numbers used as example terms for this sequence are not counted, so this list is not self-disqualifying. It is well-defined at any given time. Like many other OEIS sequences, it has infinitely many terms (more precisely, it includes all integers except a finite number). However, it may change at any time, whenever a new sequence or a new example is added to the OEIS. If included, it would therefore have to be constantly updated.
:Such integers are sometimes called "{{w|Interesting number paradox|uninteresting numbers}}" in mathematical terms, and attempts have been made to count them. The list changes, but [http://math.crg4.com/uninteresting.html#note4 in July 2009] it began 11630, 12067, 12407, 12887, 13258...
;sub[44] - Integers in increasing order of width when printed in Helvetica
:This sequence is not uniquely defined as it depends on the specific version of the {{w|Helvetica}} font used, its point size, the software used to render it (e.g. kerning algorithm), the handling of equal widths by the sorting algorithm and possibly other parameters. Also, all digits usually have the same width, with the exception of the sequence "11", which is a tiny bit narrower because a kerning pair exists in Helvetica. Without an additional tie-breaker for equal width numbers, the order is: 1 to 9 in no particular order, 11, 10 and 12 to 99 in no particular order and so on; for a particular choice of parameters the first 50 terms might be: 1, 9, 6, 2, 8, 5, 0, 7, 3, 4, 11, 61, 71, 91, 21, 51, 81, 41, 31, 19, 13, 18, 10, 12, 15, 16, 14, 17, 69, 63, 68, 79, 60, 62, 65, 73, 78, 99, 93, 98, 66, 70, 72, 75, 29, 90, 92, 95, 23, 28...
:Despite all of the above issues, and as a direct response to this comic, a well-defined version of this sequence was [https://oeis.org/A316600 added to the OEIS].
;sub[45] - The digits of Chris Hemsworth's cell phone number
:An attempt to {{w|Phishing|phish}} the phone number of actor {{w|Chris Hemsworth}}. Whilst there ''is'' a loophole to this request (the correct ordering of the digits isn't specified), knowing what digits there are in the first place may help narrow down what his number is.
;sub[46] - All integers, in descending order
:To list all integers in descending order, you would have to begin at the largest integer, but there is no largest integer, so this is impossible. It is equally impossible to list all integers in ''ascending'' order, for that matter.
:On the other hand, [https://oeis.org/A001477 A001477] is the sequence of all nonnegative integers in ascending order, as there is the smallest nonnegative integer. Also, [https://oeis.org/A001057 A001057] is the sequence of all integers, but in canonical order (i.e. by increasing absolute value).
;sub[47] - The digits of the OEIS serial number for this sequence
:This sequence is only important tautologically.
;sub[48] - 200 terabytes of nines
:This submission appears to be a joke on common video game limits for, e.g., currency or ammunition, in which the maximum a player can carry is one less than a power of 10. This sequence would be entirely useless (besides the novelty of making the OEIS waste 200 terrabytes of their storage), as there is no mental effort required to conceive a list that consists only of a single repeated term, however arbitrarily large. Such a list is also incredibly wasteful; to give a comparison, [https://phys.org/news/2016-05-math-proof-largest-terabytes.html this very large math proof from 2016] is also 200 terabytes, and requires a supercomputer to hold in its entirety. 
:200 terabytes is equal to 2 × 1014 bytes. In UTF-8, each ASCII character, including control characters such as ␂ (start of text) and ␍ (carriage return), can be represented by a single byte. If the list is presumed to be formatted as "␂9␍9␍9 ... 9␍9␃", the first term would take up 3 bytes, and all other terms would take up 2 bytes. Assuming Randall wants the file size to be 200 terabytes ''minimum'', the resulting list would be a minimum of 1 × 1014, or 100 trillion, terms long.
:Curiously, OEIS does in fact contain an entry that lists "[https://oeis.org/A010734 all nines]" which contains this proposal as a subsequence.
;sub[49] - The decimal representation of the bytes in the root password to the Online Encyclopedia of Integer Sequences server
:This would give any user the password to OEIS. Anyone can {{w|Internet troll|easily forecast}} what happens next. Perhaps the idea is to hack OEIS on the premise that accepting this sequence will force OEIS staff to populate it.
;sub[59] (title text) - The submission numbers for my accepted OEIS submissions in chronological order
:This would only be useful to Randall. If all of his submissions have been rejected, this would be an empty set. However, if this submission is accepted, the set would, by definition, include at least one number (except that this would not be known at the time of submission). Thus, as in the Russell Paradox, this set would be out of date as soon as it was accepted, since the set of accepted submission numbers would change at that point.
:Currently, it has two known numbers: 44 and 48. Other sequences suggested by Randall not listed (1-42 and 50-58, and an unknown number of submissions from 60 onwards) may or may not be accepted, but since those sequences are not known it is not known whether they were accepted.

==Transcript==
:SUB[43]: All integers which do not appear in the example terms of another OEIS sequence
:SUB[44]: Integers in increasing order of width when printed in Helvetica
:SUB[45]: The digits of Chris Hemsworth's cell phone number
:SUB[46]: All integers, in descending order
:SUB[47]: The digits of the OEIS serial number for this sequence
:SUB[48]: 200 terabytes of nines
:SUB[49]: The decimal representation of the bytes in the root password to the Online Encyclopedia of Integer Sequences server

:[Caption below the panel:]
:OEIS keeps rejecting my submissions

{{comic discussion}}

[[Category:Math]]
[[Category:Comics featuring real people]]

2983: Monocaster

2024-09-11T17:49:09Z

172.69.134.31: made the swiveling aspect more prominent

{{comic
| number = 2983
| date = September 9, 2024
| title = Monocaster
| image = monocaster_2x.png
| imagesize = 536x673px
| noexpand = true
| titletext = My competitors say the tiny single tiny caster is unsafe, unstable, and offers no advantages over traditional designs, to which I say: wow, why are you guys so mean? I thought we were friends!
}}

==Explanation==
{{incomplete|Created by a LAPTOP-CONTROLLED HAMSTER BALL - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
A caster, also spelled castor, is a small unpowered wheel, usually attached to a swiveling base. They are typically found on carts and office chairs to make them easy to move, and may be placed on heavy appliances to facilitate movement.

Randall has proposed a variant of the skateboard with only one caster on the bottom, the titular "monocaster". This may have some similarity with a {{w|Balance_board#Sphere-and-ring|"Sphere-and-ring" balance board}}, or other types, though these provide limited locomotion potential. He claims this fills an untapped hole in the market. There are plenty of vehicles with multiple wheels of varying sizes, and a smaller number vehicles with a single, large wheel (such as unicycles), but none with a single, small wheel.

The joke depends on the caster's obvious impractically in this role: the hole in the market was open ''for a reason''. The obvious drawback to any single-wheeled vehicle is that it's difficult to balance: the rider has to avoid falling forward or backward, as well as to either side. This is a major reason why one-wheeled vehicles are uncommon to begin with, but those vehicles which do exist compensate by using relatively large wheels, driven either by human power or a motor, which creates rotational inertia and allows the rider to balance simply by leaning forward.

A single, small, undriven wheel eliminates these balancing forces, meaning that the user would essentially need to balance on a single point. Also, most casters swivel, meaning that the balance point would move around under the rider's feet and make it even more difficult to balance. In addition, there's no apparent means of propulsion, which means the only way to move forward would be to either roll exclusively downhill, or use one foot to push off the ground. Either strategy would make retaining balance almost impossible.

Multiple wheeled vehicles greatly reduce the issue of balance simply by having multiple points of contact with the ground. The size of the wheels varies greatly; small, rigid wheels are generally suitable only for flat, smooth, rigid surfaces at relatively slow speeds, while vehicles expected to handle high speeds and varying road (and off-road) conditions will necessarily have larger wheels.

The "monocaster" design offers no advantages and would be nearly unrideable, making it obvious why such a vehicle has never been seriously proposed.

The title text extends the joke by listing the disadvantages mentioned above, but not providing a rebuttal.

{| class=wikitable
! scope="col" | Vehicle
! scope=“col” | Number of wheels
! scope=“col” | Wheel Diameter
! scope="col" | Explanation
|-
| 1920s Monowheel || 1 || 3 meters || A monowheel is a vehicle in which the rider sits inside a single, large, hollow wheel. Versions have existed which were hand- or pedal cranked, but the "1920s" version portrayed here is apparently motor-driven. These vehicles have generally been seen as novelties, as their stability and practicality issues limit their usefulness for actual transport.
|-
| Unicycle || 1 || 45 centimeters || Probably the best known single-wheeled form of transport, a unicycle consists of a single wheel, directly drive by pedals, with a seat mounted on top. Due to their difficulty, they've generally been used for comic performances more than practical transport.
|-
| OneWheel || 1 || 20 centimeters || A one-wheeled electric skateboard in which the user stands on both sides of a large, central wheel. The design self-balances by increasing the velocity as the user leans forward. This allows balancing and speed control to operate in a single motion.
|-
| Bicycle || 2 || 45 centimeters || A two-wheeled, pedal-driven vehicle. The relatively simple, inexpensive and efficient design of these vehicles makes them practical for transport in a variety of situations. As a result, they've long been among the most popular and widely produced vehicles in the world.
|-
| Scooter || 2 || 8 centimeters ||
|-
| Heelies || 2 || 1 centimeter ||
|-
| Tricycle || 3 || 20 centimeters ||
|-
| Scooter (three-wheeled) || 3 || 3 centimeters ||
|-
| Monster Truck || 4 || 2.5 meters ||
|-
| Car || 4 || 50 centimeters ||
|-
| ATV || 4 || 20 centimeters ||
|-
| Skateboard || 4 || 2 centimeters ||
|-
| Three-Wheel Skates|| 3 || 4 centimeters ||
|-
| Roller Skates|| 8 || 2 centimeters ||
|-
|}

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

:[A chart picturing many wheeled vehicles with a caption below the chart window. The vertical axis is labeled "Wheel Diameter", logarithmic from 1cm to 5m. The horizontal axis is labeled "Number of wheels", logarithmic from 1 to 16. From top left to bottom right, there is a person with a cap, seated in a circle, labeled "1920s monowheel", a monster truck with a skull and a lightning bolt on the side, a lorry (truck), a Cueball on a unicycle moving back and forth, a Cueball on a bicycle, a car, a Cueball using a Onewheel, a Cueball on a child's "Big Wheel" tricycle, a Cueball on a quad, a Cueball standing on a scooter, a Cueball standing on a board with one small wheel bellow, circled and labeled with two question marks, a three-wheel scooter, a skater, a Cueball using three-wheel skates, labeled "three-wheel skates", a Cueball crouching and using skates, and a small Cueball using shoes with wheels (Heelys) moving forward.]
:Caption: My new monocaster board fills a key gap in the wheeled vehicle market.

{{comic discussion}}

[[Category:Charts]]
[[Category:Comics featuring Cueball]]
[[Category:Multiple Cueballs]]
[[Category:Characters with hats]]
[[Category:Skateboard]]

2982: Water Filtration

2024-09-07T06:06:25Z

172.69.134.31: That part would be better in the table honestly

{{comic
| number = 2982
| date = September 6, 2024
| title = Water Filtration
| image = water_filtration_2x.png
| imagesize = 593x467px
| noexpand = true
| titletext = You'd think the most expensive part would be the quark-gluon plasma chamber, but it's actually usually the tube to the top of the atmosphere to carry the cosmic rays down.
}}

==Explanation==
{{incomplete|Created by a REVERSE ELECTROLYSIS RUBE GOLDBERG FILTERING MACHINE SEASONED WITH LOVE (OR AT LEAST MORE WELL WATER) - Do NOT delete this tag too soon.}}
This comic seems to be a diagram of how well water is purified, a common procedure done to make said water safe to drink. However, this well water is "purified" through a series of increasingly unnecessary, expensive, and possibly hazardous steps.

{| class="wikitable"
|-
!Step
!Real?
!Explanation
|-
|Water softener
|Real
|Softens Water
|-
|Reverse osmosis
|Real
|RO
|-
|Ultraviolet Sterilization
|Real
|RO
|-
|Autoclave
|Fake
|RO
|-
|Condenser
|Fake
|RO
|-
|Regular osmosis
|Fake
|RO
|-
|Condenser
|Fake
|RO
|-
|X-Ray Sterilization
|Fake
|RO
|-
|Carbon Filter
|Fake
|RO
|-
|Neutron Source
|Fake
|RO
|-
|Activated Carbon Filter
|Real
|RO
|-
|Gamma Ray Sterilization
|Fake
|RO
|-
|Cosmic Ray Sterilization
|Fake
|RO
|-
|Electrolysis
|Fake
|RO
|-
|Oxygen Spallation
|Fake
|The oxygen is apparently broken down, by some means, back into hydrogen (the opposite process from the fusion reactions that created it in the first place, inside stars). The oxygen nuclei contained neutrons; either these are expelled (not shown), or the hydrogen includes deuterium or tritium (to use the neutrons), or the neutrons are further broken down to give protons, electrons, and antineutrinos (not shown).
|-
|Ionizer
|Fake
|RO
|-
|Condenser
|Fake
|RO
|-
|Quark-Gluon Plasma Chamber
|Fake
|RO
|-
|Hydrogenation
|Fake
|RO
|-
|Nucleosynthesis
|Fake
|RO
|-
|Reverse Electrolysis
|Fake
|RO
|-
|Adding Well Water
|Fake
|A second pipe is linked to the first that simply feeds untreated well water into the pipes. Even if the well water is only a small portion of the faucet water, its presence has now contaminated the now incredibly pure water, making it potentially unsafe to drink if the original well water was contaminated with toxins or pathogens. This act of putting well water into the faucet after treating it may be a riff on the cultural interest in "spring water" or "pure glacial water" that is said to have additional minerals or beneficial properties but is oftentimes not meaningfully distinct from properly treated tap water.
|}

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

{{comic discussion}}

Talk:2738: Omniknot

2024-01-15T21:47:16Z

172.69.134.31:

Down the middle, that's Granny, Reef, ...(k)not sure.., ?bow line and two half hitches? and something of a plaited-knot that the name escapes me entirely right now (but an extension of the other one I can't identify). I'm sure there's a handy online catalogue of knots, to reference, though, before I try to stumble over the side-knots too. [[Special:Contributions/172.71.242.172|172.71.242.172]] 16:05, 15 February 2023 (UTC)

Binding security maximized but unbinding security minimized. RIP, tethered sailor beneath a capsized boat. [[Special:Contributions/172.70.114.78|172.70.114.78]] 16:20, 15 February 2023 (UTC)

This comic is dead on for a facetious rock climbing saying: "If you can't tie a knot, then tie a lot." Based on the tactic some climbing newcomers use, of tying tons of knots all over the place because they aren't confident that any one knot will hold. This tactic is strongly frowned upon - you should learn the right knot, use it, and don't add any extraneous ones.

Somebody on twitter posted an image with the two strings in different colours, which helps to visualize the knots:
https://twitter.com/hollowgrin/status/1625902852387352576
[[User:Rps|Rps]] ([[User talk:Rps|talk]]) 17:08, 15 February 2023 (UTC)
:Feels like this NEEDS to be included in the explanation so I added it. :) [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 05:19, 19 February 2023 (UTC)
::As per adding comment, I'd rather like to see the image in-site. (It's very difficult to open Twitter links without the seemingly undeletable Twitter app opening and telling me I need to get off my arse and get an account, so I tend not to even try.) I bashed up one of my own, for my own pleasure, but I'm not fooling myself that it's any good (basic blue/red masked to each side's rope, with directional chevrons no-masked out to show direction of pull... tried to gradient it to indicate distance as well - that looked awful!) and others' efforts would be nice to see.
::(Assuming permission isn't asked for, but refused.) [[Special:Contributions/172.69.79.132|172.69.79.132]] 15:04, 19 February 2023 (UTC)

Damn, I traced it myself and I am pretty sure the picture on twitter is better (I will not look, I will only get depressed...) I'd put that coloured picture under "transcript" ;-)[[Special:Contributions/172.68.51.140|172.68.51.140]] 18:05, 15 February 2023 (UTC)
:Nah, transcript is supposed to be all regular text, aggressively so. That link is rather pictorial. :) I added the link to the explanation instead. [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 05:19, 19 February 2023 (UTC)

I don't suppose any of you knot-loreheads would care to add an explanation/link to explain "Connecting them with a hitch" from the title text? [[Special:Contributions/172.70.254.231|172.70.254.231]] 21:58, 15 February 2023 (UTC)

A "bend" is a knot that connects two ropes or lines. A "hitch" is a knot that connects a rope (a.k.a. line) to something like a post, loop, or shackle.

Is there a mistake in the title text then, since he says to use a random hitch to connect something from the top (presumably rope in the form of a knot) to something in the bottom (presumably more rope)? [[Special:Contributions/172.70.82.186|172.70.82.186]] 22:06, 15 February 2023 (UTC)
:I think using a hitch on another rope can be valid, with one rope ACTING as said post, being all straight. For example, a rope pre-secured at both ends, and thus unable to "participate" in the knot, tying a rope to it in-between instead, such as tying a rope to a clothesline.

I tied it in real life. Once everything was tightened, the main taut portion was the Carrick bend with the other four knots slacking below, and it held pretty well. I imagine if the slack was on the other side, putting stress on the granny knot, it would be a different story. I would upload the picture but I messed up the reef knot and that pulled straight out. --[[User:Jacky720|Jack]] ([[User talk:Jacky720|t]]|[[Special:Contributions/Jacky720|c]]) 22:15, 15 February 2023 (UTC)

Sailor here. The "granny knot" is what a sailor would call a "thief's knot", and it used to be used in place of a reef knot, in some parts of the world, when stores were suspected to be going missing; the thief, after taking some of the stores, would re-lash the remainder using a proper reef knot (through force of habit) and the change of knot would give away that the stores are being taken from that pile.

Additionally, the two bends at the sides look more like sheet bends than bowlines, to me. It just looks like a rope is passed through a bite and then holds the bite together with a half-hitch. (Maybe I just can't get my head around the orientation, though?)

Lastly - is it maybe worth adding that the reason for the figure-of-eights at the tail of the rope is to act as a "stopper" knot, to prevent the tail working it's way back through the half-hitch, which would enable the bite to come apart and the whole thing to come loose? [[Special:Contributions/172.70.86.147|172.70.86.147]] 10:01, 16 February 2023 (UTC)
:A note that a Granny knot is ''not'' the Thief knot. A Granny is (often!) a mis-tied Reef, half re-handed to create a less flat version of the binding, whilst a Thief is a variation of the Reef, which has the opposite track to one of the cords to look the same at first glance (enough to catch the unwary/rushed, as you say, who might then fail to restore it as originally left).
:In fact, a knot that has been given the variations of both '''Gr'''anny and Th'''ief''' is called a "Grief", rather than be back to the original Reef (or a functionally identical reflection/rotation). [[Special:Contributions/172.71.178.64|172.71.178.64]] 12:26, 16 February 2023 (UTC)
:I corrected "bite" to "bight", as that's the correct spelling for a loop of rope or line. [[Special:Contributions/172.69.134.141|172.69.134.141]] 06:02, 20 June 2023 (UTC)
::Don't do that. Feel free to explain the 'error', but here in the Discussion pages these are words written by specified people (or at least their IPs) and you can never know if it's an error/a pun/correct in a different dictionary from yours/any other reason that it is 'wrong'. Educate people (or set yourself up to ''be'' educated), don't whitewash (perhaps incorrectly) over text that the original author may not even find has been changed. They could possibly be changed to say something they did ''not'' intend, and it would need a judgement call to, e.g., disentangle honest (mis)use of an autoantonym from a deliberate vandalism. Anyway, I have reverted your changes, but retained your comment. Not because I actually think it was ever a bad-faith edit (you are right, as far as I'm aware, though I hadn't actually picked it up myself during my own reading and replying here), just that it sets a bad principle. [[Special:Contributions/172.70.85.110|172.70.85.110]] 21:07, 20 June 2023 (UTC)

Both bowlines are the "correctly" tied sailor's bowline. There is an alternative "left-handed" version in which the end goes the other direction, coming out to the side rather than the interior of the knot. Also called the cowboy bowline, ABOK 1034.5 It is unclear which version is better. One could probably do a PhD dissertation on bowline knots. [[Special:Contributions/172.71.30.97|172.71.30.97]] 14:35, 16 February 2023 (UTC)

Scoutmaster here. I recommend the "Animated Knots by Grog" website as a knot reference. The Wikipedia entries on granny and grief knots are surprisingly useful references for how those knots differ from each other and the reef knot. 
The knot on top is definitely a <s>granny knot and not a grief knot.</s> I was wrong. :P Since the ends that terminate the knot exit on opposite sides instead of the same side, calling it a grief knot is not wrong. 
Left and right knots are bowlines because they have three working ends and one dead end. The sheet bend has two live ends and two dead ends. The center knot is indeterminate; if you cover up the ends it could be either a sheet bend or a bowline, as they have the same form. Since it appears to have four live ends it would be fair to call it "neither" as well. PhD thesis topic, indeed. 
I'd also like to point out that the capsizing nature of the reef knot is considered a feature - it affords easy untying even after being used under heavy load, such as holding a rolled up sail hanging from a yard arm. Being able to unfurl the sail by pulling a single rope is useful. As already noted on the page: if you don't want that feature, pick a different knot. [[Special:Contributions/172.71.146.36|172.71.146.36]] 14:56, 16 February 2023 (UTC)
:You can't really tell a difference between Granny and Grief (and Reef and Thief) in the above as there's not really a 'loose end' from any of those. Following all cords, the visible ends ending with the stoppers ''or'' the off-screen ends (possibly coming back on-screen from the other side, in a large loop, but we can't know that) always goes through multiple other knotted segments. Although I'd say Granny (and Reef) as default is certainly the simplest interpretation.
:And an uncollapsed Reef tends to jam itself, to not simply undo. You need to force it (or rely upon it rotating, through (improper?) use) to make it into a "cow hitch around a straight rope" form and thus an easier untie. Which you can only do if you have sufficient slack on one 'end'.
:(Not sure you could guarantee it capsizing, deliberately or incidentaly, in the omniknot situation once the whole mass gets strained. And there's no way ''that'' Reef segment can undo itsef, without plenty of other knot-failures happening, even if it does re-wrap...) [[Special:Contributions/172.70.91.100|172.70.91.100]] 18:36, 16 February 2023 (UTC)
::Yes, forcing a reef knot to capsize requires abusing the knot; i.e. applying a load onto one of the formerly loose ends. It takes less force than you may think. Try it sometime! I have occasion for this most often with kids' shoestrings.[[Special:Contributions/172.71.147.59|172.71.147.59]] 03:37, 18 February 2023 (UTC)

According to at least one interpretation I've heard, the origin of the Gordian knot story is the use of a complex knot as a sort of tamper evident seal. It won't stop a determined intruder, but it will let the the owner know someone has violated the seal (because the rope is either loose or tied back differently), and let the would-be violator know that the violation they might be considering won't go unnoticed. [[Special:Contributions/172.71.30.143|172.71.30.143]] 16:27, 16 February 2023 (UTC)

"it is knot recommended to use overly complex knots ..." -- is this meant as a joke? the wrong not is used before recommended
:Of course, obviously. :) There's no doubt in my mind. Explain XKCD editors can't help adding jokes and puns wherever possible, and this one is somewhat required, LOL! (Also, sign your comments, please) [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 06:15, 19 February 2023 (UTC)

Made it: https://imgur.com/gallery/cYQQPKq [[User:Mikemenn|Mikemenn]] ([[User talk:Mikemenn|talk]]) 16:06, 19 February 2023 (UTC)Mikemenn

Does the omniknot of all knots which do not contain themselves contain itself? [[Special:Contributions/172.69.134.31|172.69.134.31]] 21:47, 15 January 2024 (UTC)

Talk:2873: Supersymmetry

2023-12-28T03:21:38Z

172.69.134.31:

Ah, good, I was ''just'' about to tell people (on 2872's Talk page) that there was a new one... (And that we obviously need to prod the theusafBOT.) Currently, [[2872: Hydrothermal Vents]] doesn't have the 'Next' links to here, but (from last comic's experience) it might just be a matter of nudging its server-side cache a bit. I'll try the tricks I tried yesterday. [[Special:Contributions/141.101.99.101|141.101.99.101]] 20:08, 27 December 2023 (UTC)

Too bad the franchise has never introduced a Weach character (there's a couple of witches). A game with Peach as the main protagonist would be interesting, and it would give us a convenient positron. [[Special:Contributions/172.71.26.135|172.71.26.135]] 20:56, 27 December 2023 (UTC)
:If they made Weach, people would start asking for Wowser. [[Special:Contributions/108.162.245.202|108.162.245.202]] 21:53, 27 December 2023 (UTC)
::Isn't that just Bowyer? [[Special:Contributions/172.70.131.37|172.70.131.37]] 21:59, 27 December 2023 (UTC)

I think the mouse over text references mariokart? We know that Randall plays... [[Special:Contributions/172.70.200.144|172.70.200.144]] 00:43, 28 December 2023 (UTC)
: Absolutely. It's directly referring to the track ''GCN Baby Park'', found in ''{{w|Mario Kart: Double Dash|Double Dash}}'', ''{{w|Mario Kart 8|MK8}}'', and ''{{w|Mario Kart 8 Deluxe|MK8DX}}''. on the other hand, it also references ''The Legend of Zelda: Majora's Mask'' (which is already included in the explanation) [[User:SomeoneIGuess|someone, i guess]]([[User talk:SomeoneIGuess|talk i guess]]|[[Special:Contributions/SomeoneIGuess|le edit list]]) 02:21, 28 December 2023 (UTC)

I'm not that familiar with Mario or particle physics. What would the anti-Peach particle be? Bowsette? [[User:GreatWyrmGold|GreatWyrmGold]] ([[User talk:GreatWyrmGold|talk]]) 00:59, 28 December 2023 (UTC)

I think someone should add an explanation of the Mario characters... just explaining the physics isn't enough...

2418: Metacarcinization

2021-02-21T08:38:46Z

172.69.134.31: /* Explanation */

{{comic
| number = 2418
| date = January 29, 2021
| title = Metacarcinization
| image = metacarcinization.png
| titletext = Scientists still don't know how marine biologists manage to so consistently bring up whalefall ecosystems, when relevant conversational openings are so few and far between.
}}

==Explanation==
The comic strip opens with a conversation between [[White Hat]] and [[Cueball]] as they are walking together. White Hat asks Cueball if he has seen a video of a crow sledding on a roof — presumably [https://www.youtube.com/watch?v=6uXiAe7Oc-I this one], or one of its later viral reposts. ([https://laughingsquid.com/dog-rides-toboggan-down-hill/ Animals sledding] seems to be a thing lately). In this case, the crow is a {{w|Hooded Crow}}. Cueball remarks that it's a cool example of {{w|tool use by animals}}, a sign of intelligence (which corvids [Corvidae; the crow family], including crows, ravens, and [https://ocw.mit.edu/courses/brain-and-cognitive-sciences/9-20-animal-behavior-fall-2013/lecture-notes/MIT9_20F13_Lec4.pdf jackdaws], are famous for). He then points out that {{w|Tool use by sea otters|sea otters use tools}} too, namely using stones to crack open crab shells.

This in turn leads him to bring up the fact that the 'crab' body plan has evolved multiple times, a phenomenon known as {{w|carcinization}}, previously discussed in [[2314: Carcinization]]. In that strip, Cueball turned into a crab shortly after hearing about carcinization, so perhaps White Hat will likewise be transformed momentarily.

The conversation serves as an example of a {{tvtropes|WikiWalk|wiki walk}}, where a conversation naturally diverts from the original topic into a seemingly unrelated topic through a series of logical associations. Although a sledding crow has little to do with carcinization in and of itself, the conversation has managed to bridge the two topics through intermediary steps (crow using a sled, animals using tools in general, otters using stones to open crabs, crab evolutionary process).

The title and caption is a joke that, much like natural life-forms have evolved into crab-like forms multiple independent times, so too do all of Cueball's (or Randall's) conversations wiki-walk into a discussion of that evolutionary process.

In the title text, Randall jokes that marine biologists have a similar tendency to bring up {{w|Whale fall|whalefall}} (or "whale fall") ecosystems, which arise whenever a whale's carcass falls onto the deep ocean floor and are thought to provide "stepping stones" for species migration across the generally barren seafloor. Such occurrences are relatively rare, perhaps occurring once every few miles on whale migration routes, but they happen anyway, much like conversations about them. Another example of scientists tending to bring up facts from their field of study can be found at [[1610: Fire Ants]], and Randall often brings up the fact that birds evolved from dinosaurs.

==Transcript==
:[White Hat and Cueball are walking together. White Hat has his smartphone out in his hand.
:White Hat: Have you seen this video of a crow sledding on a roof?
:Cueball: Yeah! It's always cool to see animals using tools.
:Cueball: Like how sea otters use rocks to open crab shells.
:Cueball: Hey, did you know the "crab" body plan has evolved multiple times?

:[Caption below the panel:]
:Regardless of the starting topic, any conversation with me eventually converges to carcinization.
{{comic discussion}}

[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Cueball]]
[[Category:Animals]]
[[Category:Biology]]
[[Category:Convergence]]