explain xkcd - User contributions [en]

Talk:2761: 1-to-1 Scale

2023-04-11T11:00:45Z

172.68.50.73:

Really want an explanation for this one. [[User:JobbieJimmies|Melomaniac]] ([[User talk:JobbieJimmies|talk]]) 03:23, 11 April 2023 (UTC)

My comment got deleted by a bot!!! [[User:Unreliable Connection|2659: Unreliable Connection]] ([[User talk:Unreliable Connection|talk]]) 03:23, 11 April 2023 (UTC)
:RIP... [[User:JobbieJimmies|Melomaniac]] ([[User talk:JobbieJimmies|talk]]) 03:25, 11 April 2023 (UTC)
:No, UC, it just got overwritten by the 'bot, when it did its job and (re)created the whole initial state of the various pages to depict the new comic coming out. (Noting that you'd not set them all up fully/correctly.)
:That you had spotted it already and had ''just'' gotten in ahead of the 'bot clearly isn't something it was prepared to handle. But as someone spotting it can usually wait a short while for the 'bot to catch up, I don't think it's a problem. In fact, you could have just copied your old contributions into the now receptive page(s), with nary any comment. Too late now. [[Special:Contributions/172.70.90.101|172.70.90.101]] 03:44, 11 April 2023 (UTC)

:: This may have broken the next link on the previous page. --[[Special:Contributions/172.71.160.36|172.71.160.36]] 06:41, 11 April 2023 (UTC)

The lines represent the surfaces of the planets I think, so it's basically all the planets overlaid on top of each other. [[Special:Contributions/172.71.142.35|172.71.142.35]] 03:28, 11 April 2023 (UTC)

:Yup, I think it's what he meant - but I find it unlikely that the gas giants would have this clear cutoff of a "surface". [[Special:Contributions/162.158.189.241|162.158.189.241]] 03:34, 11 April 2023 (UTC)
::If there is a gas - liquid phase transition (and I think at least the gas giants have them): Why not? OK, you could see "rain" as blurring a clear cutoff, but wouldn't that also apply to Earth, then?[[User:Tier666|Tier666]] ([[User talk:Tier666|talk]]) 08:04, 11 April 2023 (UTC)

I’d think the same citation as stands for ridiculously large would also cover larger than currently exists on earth, and his that citation is not in fact needed? [[Special:Contributions/162.158.174.186|162.158.174.186]] 06:53, 11 April 2023 (UTC)

:It seems like the gas-covered worlds are explicitly those with clearly cutoff "surfaces," so maybe in those cases the cutoff is some specific gas density -- which occurs at a consistent radius throughout the planet, thus creating a flat surface. While for rocky worlds (except Venus, which is treated like a gas planet here), a density cutoff can lead to bumpiness due to terrain. [[User:Trimeta|Trimeta]] ([[User talk:Trimeta|talk]]) 03:57, 11 April 2023 (UTC)

On Twitter there seems to be concern that all planets are depicted flat. This may make this a contribution/mockery of the ongoing [https://en.wikipedia.org/wiki/Flat_Earth Flat Earth] discussions in some corners of the internet. --[[Special:Contributions/198.41.242.132|198.41.242.132]] 06:49, 11 April 2023 (UTC)

The display for an uncropped version of the image would not only be larger than any display on earth. It would be larger than earth. [[Special:Contributions/162.158.86.243|162.158.86.243]] 06:59, 11 April 2023 (UTC)
:By necessity, at least as large as Jupiter. Maybe slightly above two Jupiters (max dimension squared compared to display height*width of any common aspect ratio) if you wanted to not overlay any of the others at all. And make the lower limit a packing-problem, then add a buffer so there isn't the actual need for any to touch. [[Special:Contributions/172.70.90.253|172.70.90.253]] 10:02, 11 April 2023 (UTC)

1-to-1 scale means 'assume all planets are the same size,' right? I see Earth's grass is shown to be as large as Martian rocks, because Earth is a third again as large. (At the scale where grass is visible, Earth looks flat.) At first I thought the point was that altitude variation in cloud-tops varied so little that a gas giant shrunk down to Earth size would be featureless and have a distinct edge, but that's wrong. Ground isn't cloud-tops. Do gas giants have any solid ground? We've seen Jupiter eat comets, and it makes sense they would've collected at least some minerals and metals. According to [[https://www.teachastronomy.com/textbook/The-Giant-Planets-and-Their-Moons/Internal-Structure-of-the-Gas-Giant-Planets/|Teach Astronomy]], gas giants have Earth-sized solid cores. I'm guessing gas giants' immense gravity compresses their cores into featureless spheres, which, if scaled to Earth-size and viewed at the scale where one could see grass, would look flat. Yes?
[[User:EllenNB|EllenNB]] ([[User talk:EllenNB|talk]]) 10:14, 11 April 2023 (UTC)

There are several pieces of information here that are featured but don't make sense to me. What's the function of the dark polygon in the center? Why are the lines showing each surface going in random directions? Why is the surface of each planet so flat at a full scale rendition? When I look out my window at full sized Earth, it's not flat. It's quite bumpy, actually. But perhaps he doesn't mean these are full size, he might be saying that they're all shrunk, but the same amount, so 1:1:1:1:1... but even then, I'm totally lost.

Is this an ant on earth, over the letters "EA" ? On my monitor, set for my less-than-perfect vision, it is 15mm long, which (at a 1:1 scale) makes it a cow ant, or a large african ant. I guess people with normal vision get fire and carpenter ants instead? [[Special:Contributions/172.68.50.73|172.68.50.73]] 11:00, 11 April 2023 (UTC)

Talk:1224: Council of 300

2023-04-02T13:30:05Z

172.68.50.73:

This kind of doesn't make sense. I found the explanation for this comic through "Multiple Cueballs". There's only one. Some could argue that it's the guy speaking in the first panel, but it's only showing the front of his/her head. What if it's Ponytail? Or Hairbun? Or Rob? It doesn't show any hair.. but what if the hair is on the back of his/her head? Or what if it's a new character altogether? --[[User:JayRulesXKCD|JayRulesXKCD]] ([[User talk:JayRulesXKCD|talk]]) 11:34, 20 September 2016 (UTC)

Look at the video in the first panel[[Special:Contributions/172.68.50.73|172.68.50.73]]

This phenomenon is explained by a Google engineer [http://www.youtube.com/watch?v=oIkhgagvrjI on YouTube].
[[Special:Contributions/62.245.198.190|62.245.198.190]] 08:17, 12 June 2013 (UTC)

No reference to [http://en.wikipedia.org/wiki/Committee_of_300 Committee of 300?]. Sorry, I have no time to elaborate. --[[User:Palmpje|Palmpje]] ([[User talk:Palmpje|talk]]) 12:41, 12 June 2013 (UTC)

I think the first panel is poking fun at the complete irrelevance of merit in videos going viral (i.e. a kid crying about a celebrity or a horrible song that only got recorded because the "artist's" parents were rich). You could say it seems that merit makes a video ''less'' likely to go viral, but then you'd have to think about how a small percentage of the videos are worthy of virality, and you see that that percentage within the category of viral videos is proportionate. But, that said, a conspiracy by a dark cabal would answer more questions about this phenomenon more adequately than the commonly quoted, "people are stupid," so I think the first panel is a reference to this. Hence the, "We decree that this video meets our standards and should go viral." The explanation given above really only starts in the second panel. Plus, it wouldn't be the first time xkcd referenced and made fun of conspiracy theories.[[Special:Contributions/173.25.45.105|173.25.45.105]] 14:01, 12 June 2013 (UTC)
:To me, it's just a silly hypothetical link between the number 301 and the Committee (which I didn't know about until, like, just now). I wouldn't say that it's a biting commentary about Internet popularity, but different strokes for different folks. [[User:Alpha|Alpha]] ([[User talk:Alpha|talk]]) 16:50, 12 June 2013 (UTC)

: I can just see the guy doing finger quotes around "go viral". [[User:Wwoods|Wwoods]] ([[User talk:Wwoods|talk]]) 19:20, 12 June 2013 (UTC)

What's the helicopter-carrying-a-string video? Is that something specific and real? [[Special:Contributions/200.49.162.52|200.49.162.52]] 09:56, 13 June 2013 (UTC)

:Looks like a black helicopter (a common conspiracy theory) to me. [[Special:Contributions/141.101.98.130|141.101.98.130]] 19:41, 6 September 2016 (UTC)

301 is the number of people in the council plus the first regular person to view it. It's an obvious point, but we seem like we want to be complete. Not sure where to add it, so I'll let wiki-magic take care of that. [[Special:Contributions/76.106.251.87|76.106.251.87]] 19:07, 13 June 2013 (UTC)

The council member in the second panel seems to have a collar. Has Randall every drawn figures like that? [[Special:Contributions/141.101.96.120|141.101.96.120]] 12:45, 15 November 2013 (UTC)

The collar looks like a cape to me. {{unsigned ip|108.162.231.220}}

2100: Models of the Atom

2023-03-22T07:06:05Z

172.68.50.73: /* Explanation */

{{comic
| number = 2100
| date = January 18, 2019
| title = Models of the Atom
| image = models_of_the_atom.png
| titletext = J.J. Thompson won a Nobel Prize for his work in electricity in gases, but was unfairly passed over for his "An atom is plum pudding, and plum pudding is MADE of atoms! Duuuuude." theory.
}}

==Explanation==

This comic humorously describes the changing view of what an {{w|atom}} is. This has happened so much it seems that we never really knew what we are looking at, and there have been many competing theories aside from the mainstream ones we are taught in school. He lists major depictions in the history of our understanding of an atom, and adds a few humorous ones in to poke fun at how diverse, contentious, and in retrospect often foolhardy, this history has been.

;Small hard ball model
The first model shown, in 1810, is said to be a "small hard ball model." Around this time, {{w|John Dalton}} published his textbook ''A New System of Chemical Philosophy'' which linked existing ideas of atomic theory and chemical reactivity to produce a combined {{w|law of multiple proportions}} which proposed that each chemical element is comprised of a single unique type of atom, and introduced the concept of {{w|Molecular mass|molecular weight}}. Dalton's theories form the basis of what is known today as {{w|stoichiometry}}, which underpins chemical reactivity. As atoms were considered at this time to be the smallest possible division of matter the scientific community thought of them as "hard round balls" of different sizes; thus the name described here. The "small hard ball" model is still commonly used when teaching and discussing chemical molecules which do not require the level of detail provided by more advanced models, with atoms represented as small, hard, round balls connected by sticks representing chemical bonds.

;Plum pudding model
In the late 19th and early 20th centuries, the study of these "atom" things faced a crisis: where would the newly discovered "{{w|electron}}s" go? In 1904, physicist {{w|J. J. Thomson}}, who discovered electrons, had an idea: maybe the electrons were small point charges moving around in a big mass of positive charge. This was the "{{w|plum pudding model}}", the second model on the comic, called this because people imagined the positively charged mass as a "{{w|Christmas pudding|plum pudding}}". (The title text references Thomson (although misspelled as "J.J. Thompson") as well, along with the humorous observation that plum puddings themselves are made of atoms.) The problem with this approach is that same charges generally repel, resulting in the more mobile or unbalanced charges forming a surface shell around the others, attempting to escape, rather than being content to being randomly distributed among them.

;Tiny bird model
There were many competing ideas in the formative years of what-are-atoms-made-of-ology; [[Randall]] makes up a 1907 "tiny bird model," which he suggests might have fit well in the relative chaos of the period. In this model, four birds surround the small hard ball at equal distances to one another. Two of them are singing and the other two are not and all birds are opposite to their identical bird. The non-singing birds balance the singing birds like electrons and protons. This model might be mocking the strange and sometimes illogical models that were presented for the shape of an atom.

;Rutherford model
The tentative winner in the battle was the model of Thomson's student {{w|Ernest Rutherford}}, who discovered from electrostatic scattering experiments that the positive charge seemed to be concentrated in the center of the atom, and proposed his {{w|Rutherford model}}, or "planetary model", in 1911, where electrons orbit a very concentrated positive charge. This model has often been compared to the orbit of the planets around the sun, with the electrostatic attraction of the electrons and protons shaping the orbits, rather than gravity. This is the fourth model in the comic.

;Bohr model
The Rutherford model could not explain the discrete spectral lines in absorption and emission spectra. It also did not explain why electrons did not spiral in to the nucleus. {{w|Niels Bohr}} patched the model up by proposing that electrons could only exist in distinct "energy levels" at discrete distances from the nucleus. The 1913 "{{w|Bohr model}}", the fifth model shown here, was part of beginning quantum mechanics. Physics behaves differently at the small scale of atoms than the large scales we are more familiar with.

;Nunchuck model
Randall facetiously suggests a "{{w|Nunchaku|nunchuck}} model", the sixth model shown, of a packet of protons swinging a packet of electrons around. One can imagine a handle filled with electrons bonded by the strong nuclear force to a chain made of neutrons, bonded again by the strong nuclear force to a handle made of protons. The heavier protonic handle acts loosely as an orbital center as the electron-filled opposite handle swings wildly around it, attempting to resolve its electrostatic attraction within the restraints of its chain.

;Chadwick model
The next refinement was in the structure of the nucleus. Note that at this time, nobody thought of splitting up the nucleus into {{w|proton}}s and {{w|neutron}}s. But pretty soon people noticed that protons and neutrons existed; {{w|James Chadwick}}, who discovered the neutron, figured that the atom had a nucleus of neutrons and protons, along with a bunch of electrons orbiting around it in a Bohrish manner. This is what the layman today often thinks of as an atom, and is the seventh model shown here.

;538 model
The eighth model shown is a made up "538 model," in 2008. {{w|FiveThirtyEight}} is a statistical analysis website that gained fame in 2008 for predicting every race but 2 correctly in the {{w|2008 United States presidential election|US presidential election}} and predicting every state and Obama's win in the 2012 election. Unlike most other media and polling institutes it saw a rather high probability of 29% for Trump to win the 2016 election by summing up the uncertainties in all the battle states. It has since been known for making mathematical models for everything; the model jokingly suggests that 538 has modeled and presumably made predictions about the atom. The {{w|pie chart}} shows the statistical composition of neutrons, protons and electrons, 38%, 31%, and 31% respectively. This could either be the average of a massive body with several isotopes or represent gallium-69, the most abundant {{w|Isotopes of gallium|isotope of gallium}}, with 31 protons, 31 electrons and 38 neutrons. FiveThirtyEight has previously been mentioned in several xkcd comics, including in [[477: Typewriter]], [[500: Election]], [[635: Locke and Demosthenes]], [[1130: Poll Watching]], [[1779: 2017]], and [[2002: LeBron James and Stephen Curry]]. It's appropriate to list the 538 model as a precursor to the quantum model, as it is a step towards considering the likelihood of different quantities of subatomic particles to be in different volumes of space, rather than considering them as strictly kinematic particles. The comic moves this development into 2008 in support of this joke, when it was actually made much earlier.

;Quantum model
But the Chadwick model is not what scientists endorse today.
{{w|Maxwell's equations|The theory of electromagnetism}} says that accelerated charges, like the electrons circling, would lose energy emitted as electromagnetic waves and would quickly orbit into the nucleus. Bohr only postulated that this would not happen, but his model could not explain why. Another problem{{Citation needed}} is that atoms, even the hydrogen atom, are not flat - which they would be, if a single electron orbited in a circular or elliptical trajectory (the circular motion of charge results in a magnetic moment; Otto Stern and Walter Gerlach {{w|Stern–Gerlach experiment|showed}} that independent from the direction of the measurement the angular momentum - for certain elements - always has the maximum positive or negative value, i.e. not only the radius, but also the angular momentum is quantized - and never zero. You cannot 'look at' the atom from above and 'see' the orbital circle. It always 'seems', as if you 'looked' from the side and would measure the full magnetic dipole. Stern and Gerlach actually saw the spin of an electron of the silver atom instead of the angular momentum, which is according to quantum mechanics 0).
Today (i.e. actually since 1926, 29 years after the discovery of the electron) physicists subscribe to a quantum model, which is the ninth model shown here. Instead of electrons with definite location and momentum (~speed), the parts of the atom are described by probability fields of possible locations and momentums. The changes in momentum probability normally cancel each other out, so there is no electromagnetic radiation. This is very abstract, and in the last model, the model is postulated to get so abstract that it is just a "small hard ball surrounded by math" model, the last model shown. This then is remarkably similar to the model we started out from, the "small hard ball model" (without the math).

;“Small hard ball surrounded by math” model
The picture for the "small ball surrounded by math" depicts a circle with several numbers around it. While the numbers seem to symbolize the "surrounding math" in a general sense, some of them suggest constants used in actual mathematical equations or other numbers related to the quantum model. The shapes and densities of the atomic orbitals are calculated with the {{w|Schrödinger equation}}, which is complex and difficult to solve. For this reason atoms are generally precisely considered in only very simple simulations, and the details of interactions of many atoms at large scales that form our daily lives are incredibly hard to precisely understand and predict on an atomic level. It comes down to "these roundish things we call atoms are moving around in these approximate ways obeying this complex equation with too many numbers involved in most situations to accurately model, so let's use a different, empirically derived formula that describes the behavior of the system in general."

This model is probably a reference to the {{w|mathematical universe hypothesis}} and, as a striking case of [[2203: Prescience|prescience]], may be seen as a prediction of April 2020’s {{w|Stephen Wolfram#Wolfram Physics Project|Wolfram Physics Project}}.

==Transcript==
:[Heading:]
:<big>Models of the Atom</big>
:over time

:[What follows is a progression of depictions of atoms.]

:[A ball.]
:1810
:Small hard ball model

:[A 'pudding' inside of which there are electrons.]
:1904
:Plum pudding model

:[A ball, with four birds perched on it and two of them singing.]
:1907
:Tiny bird model

:[A ball with electrons orbiting chaotically, in all directions, around it.]
:1911
:Rutherford model

:[A ball with electrons circling around it.]
:1913
:Bohr model

:[A nunchuck swinging, with the left stick filled with protons and the right stick filled with electrons.]
:1928
:Nunchuck model

:[A nucleus with protons and neutrons, with electrons circling around it like the Bohr model.]
:1932
:Chadwick model

:[A pie chart. 38% is allocated to neutrons, 31% to protons, and 31% to electrons.]
:2008
:538 model

:[A nucleus with clover-like orbitals around it and surrounded by two outer partly dashed circles.]
:Today
:Quantum model

:[A ball surrounded with numbers.]
:Future
:"Small hard ball surrounded by math" model

{{comic discussion}}

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