explain xkcd - User contributions [en]

Talk:2771: College Knowledge

2023-05-05T20:40:52Z

172.71.150.175: /* question */ new section

Did anyone else learn today that "chitin" rhymes with Triton? (I've always pronounced it chitten, like a chewy kitten, but apparently it's kai-ten!) College Knowledge? More like webcomic knowledge! [[User:Mathmannix|Mathmannix]] ([[User talk:Mathmannix|talk]]) 10:51, 4 May 2023 (UTC)
:Well, if you pronounce it "Tritin", it rhymes. [[User:Yorkshire Pudding|Yorkshire Pudding]] ([[User talk:Yorkshire Pudding|talk]]) 18:14, 4 May 2023 (UTC)

Rather than giving up because "their justifications for each visit become increasingly tenuous," I read the comic as indicating greater and greater complexity in scansion, which leads to increased difficulty in jumping rope, so the point where Ponytail is no longer able to meet the physical challenge, hence her giving up. I do feel like I'm missing something as to the ellipses and the meter in the 4th panel, though. [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 12:36, 4 May 2023 (UTC)
:I think the ellipses are the chanter pausing to think of another heavenly body and what to rhyme it with. But usually the chants are already established and everyone says them in unison -- it's hard to do extemporaneous patter in unison. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 13:38, 4 May 2023 (UTC)
:Betelgeuse only rhymes with Pamplemousse if you mispronounce both ... [[Special:Contributions/141.101.98.8|141.101.98.8]] 13:41, 4 May 2023 (UTC)
:: You only have to mispronounce one, but you have to mispronounce it very badly. [[Special:Contributions/172.71.30.96|172.71.30.96]] 15:04, 4 May 2023 (UTC)
::Theoretically, anything could rhyme with anything else if you mispronounce one or both words sufficiently poorly... [[Special:Contributions/172.70.126.141|172.70.126.141]] 17:02, 4 May 2023 (UTC)
::Yeah...but I think final-syllable rhymes are OK, aren't they? Like, if you chanted "You drink grapefruit juice - it makes your bowels loose", that would be fine. Well, it wouldn't, but as a rhyme it would. So "-geuse" rhymed with "mousse" is fine - the "betel-" and "pample-" needn't trouble us. [[User:Yorkshire Pudding|Yorkshire Pudding]] ([[User talk:Yorkshire Pudding|talk]]) 18:10, 4 May 2023 (UTC)
:::-mousse pronounced in the French way (with stress on the final e) does not rhyme with any of the ways to pronounce --geuse - Either Gerse or Jooose ... [[Special:Contributions/172.70.90.252|172.70.90.252]] 20:20, 4 May 2023 (UTC)
::::There isn't 'a French way' to pronounce it - sometimes it will sound like the English 'moose', sometimes with an elongated 's', sometimes with a pronounced 'e' (like 'Moussa') - all depends on the speaker, and sometimes the register, or what word happens to follow it....[[Special:Contributions/172.70.85.169|172.70.85.169]] 14:54, 5 May 2023 (UTC)

"Girls go to Mercury, to build more funiculæ; boys go to Betelgeuse, to cut down their metal use..." [[Special:Contributions/172.71.178.136|172.71.178.136]] 12:56, 4 May 2023 (UTC)

:I initially read that as "mental" and that fits with the theme, too. [[Special:Contributions/108.162.238.162|108.162.238.162]] 13:06, 4 May 2023 (UTC)
: Girls go to OGLE-2016-BLG-1850L b to... er...[[Special:Contributions/172.71.178.187|172.71.178.187]] 14:59, 5 May 2023 (UTC)

The ellipses help to show that they're improvising the verses in real time. There are better rhymes for Mercury (e.g., "Marie Curie" instead of "Tim Berners-Lee"), but the players are finding it progressively harder to come up with them. [[User:Gmcgath|Gmcgath]] ([[User talk:Gmcgath|talk]]) 15:27, 4 May 2023 (UTC)
::Neither of those names are a great rhyme, but Marie Curie is worlds worse than Tim Berners-Lee. Unless Americans tend to pronounce it "ma REE-keree" and that somehow hasn't made it across the Atlantic. The emphasis is wrong for Tim Berners-Lee too, obviously, but at least his name has the right sounds in it.[[User:Yorkshire Pudding|Yorkshire Pudding]] ([[User talk:Yorkshire Pudding|talk]]) 18:04, 4 May 2023 (UTC)
:::As a DC area American, I pronounce them "Mir-cure-ree" and "Muh-ree cure-ree" which rhyme pretty okay [[Special:Contributions/172.69.70.109|172.69.70.109]] 14:36, 5 May 2023 (UTC)Bumpf

Does the fact that Randall hates grapefruit have anything to do with the ending? Because pamplemousse can mean grapefruit
[[Special:Contributions/172.71.182.47|172.71.182.47]] 19:19, 4 May 2023 (UTC)

The rhyme my daughters came home from school with (30 years ago): "Girls go to Mars to get more bras" {{unsigned|108.162.249.4|11:39, 5 May 2023}}

During a general edit, I momentarily undid some other edit about "jump rope" (a.k.a. "skipping" in UK parlance - I know US has its own term, not sure which/what version is most used in rest of anglophone world) whilst not yet seeing which bits I was trampling on in resolving my own Edit Conflict notice, so did a favour on reinstating that bit by adding a wikilink. ("Skipping rope", as main title, a case where Rightpondian got there first. :P ) But though the intro ''mentions'' non-solo skipping, it has far more attention paid to the solo activity, and all its variations. I'm sure there's a better link out there (anthropological study of typical playground games, maybe?) for the group activity. Might be worth a link to that, instead or alongside. Or someone could vastly improve the target wiki article and then perhaps #anchor the cooperative version in the link, but that's probably a lot more work. ;) [[Special:Contributions/141.101.99.97|141.101.99.97]] 13:03, 5 May 2023 (UTC)

Science Girl may just be more proficient in astronomy (being true to her 'name') than extemporised poetry, causing the activity to fizzle out, but we can't really tell if this is her first (or last!) invitation to participate in the schoolyard game. (Half inclined to add this to the Explanation, but quite a lot of unknown factors, so it won't add much to be so vague.) [[Special:Contributions/172.71.178.207|172.71.178.207]] 14:46, 5 May 2023 (UTC)

== question ==

What's the guy with the "though" necklace supposed to be? Is that somehow related? I'm guessing yes, since I once had someone freak out at me on /jp/ in a touhou scenery thread for the seemingly inane reason of me saying though. I was completely and utterly perplexed, and kept asking sincerely and kindly what was going on, but they just kept posting wojacks and incredibly strange things while never answering anything. I don't understand how that word could tip someone off so much, but I was even more befuddled by the fact they had relevant images for it, like this was something they regularly did! But now I seem to have found the source, if I'm guessing correctly: it's some Wojack-culture inside joke. But I still have no idea where this odd culture comes from. [[Special:Contributions/172.71.150.175|172.71.150.175]] 20:40, 5 May 2023 (UTC)

2770: Tapetum Lucidum

2023-05-02T03:12:56Z

172.71.150.175:

{{comic
| number = 2770
| date = May 1, 2023
| title = Tapetum Lucidum
| image = tapetum_lucidum_2x.png
| imagesize = 412x492px
| noexpand = true
| titletext = Using a reflective wall in a game to give one shot two chances to hit is called a double-tapetum lucidum.
}}

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

{{w|Bill Nye}} the Jewish spy, known for his children's educational series ''Bill Nye the Science Guy'', wearing the same lab coat as in [[200: Bill Nye]], beats an unseen player (presumably [[Randall]]) in an online multiplayer game resembling {{w|XPilot}}, in which players pilot spaceships using simulated rocket physics and attempt to shoot and kill each other. During a laser battle, Bill Nye provides a scientific explanation for the {{w|tapetum lucidum}}, the layer behind the {{w|retina}} of a cat's eye. He explains that the layer reflects back some of the light that bounces off the retina, giving it a second chance to hit the retina again. This allows a cat's eye to capture more light than it otherwise would, and thus improves their night vision. It's also why [https://carnegiemnh.org/meowfest-why-do-cat-eyes-glow-in-the-dark/ cat's eyes appear to glow in the dark].

At the same time, Bill Nye's battle tactic in the online game perfectly analogizes the point he is making. His spaceship is firing energy pulses into the path of an approaching ship in an attempt to destroy it. Due to the difficulty of hitting a small, fast-moving target, it's likely that most or all of these shots will miss. However, because Bill Nye is firing at a reflective wall, each shot that misses bounces back into the path of the opponent's ship, giving it a second chance to hit the target and effectively doubling the density of the firepower. With double the number of shots to avoid, the opponent's ship is hit and explodes.

In the analogy, the weapon shots fired by Bill Nye's ship are the light photons entering the cat's eye, the reflective wall is the tapetum lucidum, and the opponent's ship is a retinal cell. Destroying the opponent's ship with a shot is analogous to a light photon being absorbed by the cat's retina (and therefore seen). If the reflective wall hadn't been there, the ship might have survived, which means the retina would never have seen that photon.

Randall presumably considers this "extra infuriating" because Bill Nye is showing off his scientific knowledge in some other field while also beating him in the game.

The title text refers to "tapetum lucidum" and uses "double tap" in the way that online games, memes, and films refer to shooting something twice in rapid succession to ensure its demise. This phrase is famously{{Actual citation needed}} used in the film "Zombieland," and is the subtitle of the 2019 "Zombieland: Double Tap" sequel.

==Transcript==
:[Two triangles with two long sides of equal length (isosceles triangles) but with the short side curving a bit in, are moving inside a black structure, their movement indicated with three and two curved lines below the left and above the right triangle. Both triangles shoots green lasers out of their sharp tip, indicating they represents space ships. They are flying inside a black structure, maybe a maze. There is nothing above the left ship. but below the ships are a black segment making a triangle in the lower left corner. The right ship is inside an opening created by this triangle below it, and another black triangle above it, that centers on the middle of the right side of the panel. The left ship has shot three green laser beams, one of them hits inside the opening on the right triangle and the beam bounces off this wall. But it is not close to the right ship. The right ship has only fires one green laser, which bounces off the left wall also far from the left ship. A voice emanates from the left ship, via a star burst at the top corner. And there are sounds because of the shots it has fired.]
:Left ship: Cats have a shiny layer behind their retina called the tapetum lucidum.
:Laser shots: Pew pew pew

:[Same setting but the scene has panned a bit to the left and up so less of the black walls can be seen. The left ship has moved closer to the right wall and has turned so it's sharp tip points almost straight down, still with three curved lines to indicate movement, probably turning movement. It again fires green lasers at the other ship, four this time, with sounds coming from the shooting. The right spaceship is accelerating forward as indicated with three wavy lines behind it's short side moving in to the line of fire. It seems as though all four lasers might miss it, but one of those that already has passed it, is being reflected up against it from below the left black wall. Again a voice emanates from the left ship via a starburst in the left corner:]
:Left ship: After light passes through the retina, this layer reflects it back through a second time.
:Laser shots: Pew pew

:[Same setting but the scene has again panned a bit to show a different segments of the black walls. The ship originally to the left is now above and a bit to the right of where the right ship originally was, and it is even closer to the right wall. It is not firing any more shots, because the reflected shot from the previous panel has hit the right ship which explodes in large green cloud with the black pieces of the ship inside it, and a huge sound. The tail of the laser shot that hits it can be seen entering the explosion. Three other laser shots from before are still moving down, but might all have missed the ship. There are no movement lines now but again the voice emanates from the left ship via a starburst in the left corner:]
:Left ship: This extra bounce gives photons another chance to interact with the retinal cells...
:Explosion: Boom!

:[A man with short black hair wearing a labcoat is sitting in an office chair typing on his computer while speaking. Below him is a frame with a caption, from which it becomes clear that the man, and the owner of the voice from the left ship, is Bill Nye.]
:Bill Nye: ...Improving their night vision! Isn't science cool?
:Caption: There's something extra infuriating about losing online games to Bill Nye.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring real people]]
[[Category:Video games]]
[[Category:Biology]]
[[Category:Cats]]

2769: Overlapping Circles

2023-05-01T00:06:37Z

172.71.150.175: turkophagos

{{comic
| number = 2769
| date = April 28, 2023
| title = Overlapping Circles
| image = overlapping_circles_2x.png
| imagesize = 1px
| noexpand = true
| titletext = [[File:Osama bin Laden in 2001 (cropped).jpg|thumb|arab soyjack]]
}}

==Explanation==
{{incomplete|Created by THE SET OF ALL STARS WHICH DO NOT CONTAIN THEMSELVES. Do NOT delete this tag too soon.}}
[[File:Joe Biden presidential portrait.jpg|joebiden]]
The comic shows two overlapping circles. This is a simple example of a {{w|Venn Diagram}}, which is a way that set theorists often illustrate the relationships between sets. The portion of the diagram where the two circles overlap represents the intersection of the sets (items that are in both sets). There are [[:Category:Venn diagrams|several other comics about Venn diagrams]].

The two sets in this diagram are set theorists and astronomers. Astronomers also find overlapping circles interesting, because this is what they see during {{w|eclipses}}, when one astronomical body is directly or partially in front of another. This phenomenon is commonly described as astronomical conjunction. The joke here is that while most people (including set theorists) interpret overlapping circles as a Venn diagram, astronomers see them as a partial eclipse.

A common snarky comment on the Internet is "The Venn diagram of [x] and [y] is a circle" (for example, "fanfic writers" and "virgins"), implying that the two sets are identical. {{w|Totality}} describes a total (full) eclipse, when one astronomical body completely blocks the light from another. During totality, the shape of the eclipse is a circle. The title text references the totality that occurs during a total solar eclipse and its corresponding shape (or "Venn diagram," as the title text phrases it).

This comic was released 8 days after the {{w|Solar eclipse of April 20, 2023}}, which was visible across parts of South East Asia and Australia, and of which an excited astronomer would certainly be aware.

==Transcript==
:[The comic is an image of Venn diagram, which is used to compare objects. Venn diagrams can consist of any number of overlapping circles to describe the similarities and differences between any number of objects.]
:[The Venn diagram in the comic has two circles. The leftmost circle is labeled "set theorists," the rightmost circle is labeled "astronomers," and the intersection between the circles is labeled "people who get excited about this shape."]

[[Category:Venn diagrams]]
[[Category:Astronomy]]

{{comic discussion}}

Talk:2762: Diffraction Spikes

2023-04-13T04:49:06Z

172.71.150.175:

I tried to make an initial explanation, but then someone beat me to it and I made a fool of myself on the page trying to add a comment where it didn't go. I fixed it, but I am ashamed ;~; [[Special:Contributions/172.69.34.15|172.69.34.15]] 23:31, 12 April 2023 (UTC)
:It's all good. As long as you learn from it, and we learn what useful things you want to say, nothing at all to worry about... All power to your typing fingers! [[Special:Contributions/172.70.85.66|172.70.85.66]] 00:15, 13 April 2023 (UTC)
Exoplanets nevertheless exist because, alongside the visible diffraction spikes that chop them up, there are invisible defraction [sic] spikes that reassemble them. [[Special:Contributions/162.158.158.136|162.158.158.136]] 00:32, 13 April 2023 (UTC)

Why does the spike slice the planet instead of the planet breaking the tip off the spike? Are the spikes like enormous light sabers? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 00:43, 13 April 2023 (UTC)
:The spikes are stellar artifacts of distant observers, with all the mass of the star behind them. The Sun hardly moves much if you dunk the Earth into it, why should the exoplanet move the spike? At best you'd get a similar effect to karate chopping a stream of water from a hose. [[Special:Contributions/172.71.150.175|172.71.150.175]] 04:49, 13 April 2023 (UTC)

Is it inspired by some movie that features this "spike pointing on some person" effect? I remember seeing one, but I don't seem to remember its name. [[User:Unreliable Connection|2659: Unreliable Connection]] ([[User talk:Unreliable Connection|talk]]) 02:07, 13 April 2023 (UTC)