Talk:3103: Exoplanet System

2025-06-17T12:12:59Z

Robisodd:

"Faint dust cloud that will cause several papers to be retracted" could refer to either Fomalhaut b (former proposed exoplanet that turned out to be a dust cloud) or Tabby's Star (star with odd irregular dimming pattern likely due to a dust cloud, but was briefly thought by some to be an alien megastructure the speculation of which caused the media to lose their shit). [[User:Erika lovelace|Erika lovelace]] ([[User talk:Erika lovelace|talk]]) 19:53, 16 June 2025 (UTC)

Somebody should word it better but the idea of a black hole accretion disk having a habitable zone is pretty typical for Randall brand humor. [[Special:Contributions/130.76.187.35|130.76.187.35]] 20:12, 16 June 2025 (UTC)
:I think it's actually a reference to [[wikipedia:Interstellar (film)|''Interstellar'']]. In that movie three planets are sort of in the habitable zone of a giant black hole's accretion disk. Whether that means they have to be in the accretion disk, or whether they can be outside it but still in the habitable zone of the disk's radiation, I'm not sure. -- [[User:Ken g6|Ken g6]] ([[User talk:Ken g6|talk]]) 00:17, 17 June 2025 (UTC)
:An alternative reading of #18 is that the planet may or may not be too hot for rocks to solidify at the surface. (Even if this turns out to be implausible, Randall does stretch the bounds of plausibility on occasion.) [[Special:Contributions/87.75.45.216|87.75.45.216]] 08:36, 17 June 2025 (UTC)
:An accretion disk is also found around a star. So the exoplanet may be in the zone where planets may actually form. (talking about the title text) [[Special:Contributions/129.27.217.99|129.27.217.99]] 08:59, 17 June 2025 (UTC)
:: An accretion disk forms around my desk. Whether or not it counts as habitable is debatable, though. [[Special:Contributions/82.13.184.33|82.13.184.33]] 09:15, 17 June 2025 (UTC)
:Yeah, the Earth is thought to have formed from the accretion disk of the Sun 4.5b years ago. It probably has nothing to do with black holes. [[User:Robisodd|Robisodd]] ([[User talk:Robisodd|talk]]) 12:12, 17 June 2025 (UTC)

2658: Coffee Cup Holes

2022-08-15T12:29:12Z

Robisodd: /* Explanation */ Fixed "whole/hole" typo

{{comic
| number = 2658
| date = August 12, 2022
| title = Coffee Cup Holes
| image = coffee_cup_holes.png
| titletext = Theoretical physicist: At the Planck length, uncountably many.
}}

==Explanation==
{{incomplete|Created by a CAFFEINE MOLECULE WITH A HOLE DRILLED IN ITS SIDE. Do NOT delete this tag too soon.}}
This comic depicts people in different fields of study answering the question, "How many holes are there in a coffee cup?" and also compares this to what a normal person would say.

This question has different interpretations, entirely dependant upon the definition of a hole. The type of {{w|coffee cup}} shown in the comic is with a handle (like a {{w|Mug}}), but [[Randall]] calls it a cup and there are also cups with handles on the Wikipedia page for coffee cups. Most people would recognize that there is a hole through the handle.

[[File:Mug and Torus morph.gif|thumb|200px|The coffee mug and donut shown in this animation both have topological genus one.]]

[[Ponytail]], a {{w|topology|topologist}}, states the coffee cup belongs in the {{w|Genus (mathematics)#Topology|genus}} of one hole. A common joke is that topologists can't tell the difference between a coffee cup (with handle) and a {{w|doughnut}} since they're {{w|Homeomorphism|homeomorphic}} to each other — meaning they have the same genus, i.e one hole. From the topologist's point of view, the coffee cup definitely has one hole, which corresponds to the opening created by the cup handle. A cup without a handle would have zero holes, as it is equivalent to a dinner plate, just an indentation in the surface. See [[2625: Field Topology]] for more information about topology.

[[Hairy]], a normal person, is not sure (the acronym "IDK" stands for "I don't know") and asks for clarification about whether the opening at the top counts as a hole. This shows flaws in the question, which suffers from the mathematically imprecise, ambiguous common usage of the word hole. Topologists would refer to the opening as a concavity, not a hole, and while they consider such geometrical properties generally outside their field, most practical applications of topology do involve geometric components. Hairy would say one for the handle, and two if the opening counts as a hole, which he is not certain the one asking the question thinks.

[[File:Double torus illustration.png|thumb|left|200px|A genus two surface]]

[[Hairbun]], a philosopher, answers the question with an elucidating counter-question, considering a hypothetical scenario. Drilling a new hole should increase the number of holes by one. After the hole has been drilled, the coffee cup with handle has two holes according to topologists. Therefore, the philosopher's question requires the original questioner to reveal the answer to their own question. The drawing clearly shows the two holes that would be in the cup after drilling, and thus makes it clear that the opening is not considered a hole if there is no way through for the coffee. (So from that drawing the original answer is again one hole).

[[Image:Point cloud torus.gif|thumb|200px|A point cloud of a genus one surface]]

[[Cueball]], a chemist, looks at the coffee in the cup on a molecular level, which means it has very many holes: 1,000,000,000,000,000,000,000 (10<sup>21</sup> or 1 sextillion) “in the [https://chemapps.stolaf.edu/jmol/jmol.php?model=CN1C%3DNC2%3DC1C%28%3DO%29N%28C%28%3DO%29N2C%29C caffeine] alone.” One molecule of caffeine has two rings of bonds with holes in them, so Cueball is talking about 500 quintillion molecules, or 0.00083 {{w|mole (unit)|moles}}. As the molecular mass of {{w|caffeine}} is about 194 grams per mole, [[Randall]] must think that the mass of caffeine in a typical cup of coffee is 161 milligrams. The coffee could have other holes, depending on the type of coffee; for example, espresso contains significant amounts of niacin and riboflavin, which have one and three rings in their chemical structure, respectively. However, bonds are not sticks as portrayed in many molecular models. The "holes" in the middle of a molecule's rings are not completely empty but instead merely have lower electron probability density through the middle than other parts of the bonds. So the point-cloud duality of {{w|Bonding molecular orbital|electron orbitals and bonds}} might not satisfy a topologist's, normal person's, or philosopher's criteria for a connected substrate in which holes may be formed.

[[Image:World lines and world sheet.svg|left|thumb|200px|{{w|String theory}} describes the {{w|worldline}}s of point-like particles as {{w|worldsheet}}s of "closed strings," forming topological holes.]]

In the title text, a theoretical physicist looks even deeper, at the subatomic scale of {{w|Planck units}}. Since fundamental particle interaction is governed by fundamental forces and collision (per the {{w|Pauli exclusion principle}}) instead of tensile or ductile solid connectedness, the theoretical physicist posits that any definition providing for a single hole would also describe a number of holes akin to the factorial of the number of particles in the universe,[https://tel.archives-ouvertes.fr/tel-02341882/document] or at least within the cup's {{w|light cone}}, which is a number impractical to accurately count, but not uncountable in a mathematical sense.

The main joke is that the number of holes depend both on what scale you are looking at the world, and also on the common uses of the word hole, which is also used when someone digs a bit into the ground. A hole in the ground should go all the way through (or easier, down and up again another place) before it is a real hole. Since a hole is something that some other thing should be able to pass through. But if people dig in the ground the result is called a hole, just like the opening in a coffee cup (without a handle) or a bottle of beer is called a hole, even though they are equivalent to a dinner plate, which normal people would never say had a hole.

The topological discussion here regarding cups and doughnuts is related to the question of how many holes there are in a human, which is excellently answered in Vsauce's video
[https://www.youtube.com/watch?v=egEraZP9yXQ How Many Holes Does a Human Have?]. This also takes a god look at the topological difference between a paper cup and a mug with handle.

==Transcript==
:[The first panel has text only and is phrasing a question:]
:<big>Q:</big>
:How many holes are there in a coffee cup?

:[Each of the next four panels has a caption at the top to indicate the kind of person answering the question. In the first of these Ponytail stands holding a coffee cup in its handle.]
:Caption: Topologist
:Ponytail: One.

:[In the next panel Hairy stands to the right of Ponytail, holding the coffee cup in its handle at an angle so he can to look into it.]
:Caption: Normal person
:Hairy: IDK, does the opening count as a hole?

:[In the next panel Hairbun is shown in closeup, holding her hand out palm up to indicate two drawings of coffee cups with handles to her left. The top drawing is larger and shows the cup with coffee inside, and a hole drilled at the bottom part of the side away from the handle. Coffee pours out of this hole. Beneath and further left is a smaller version of the same cup, but now without coffee. Instead two curved arrows goes from above to below through the hole of the handle and the hole now drilled in the bottom part of the cup. Each arrow is labeled with a question-mark.]
:Caption: Philosopher
:Hairbun: To answer that question, consider another: If we drill a hole in the side, how many holes are there now?
:?
:?

:[Cueball, without any cup, stands with a drawing of a caffeine molecule above and to the right of him. It has two "rings" with 5 and 6 atoms. Those rings are connected along one side. There are 9 "edges" on this, three of those has one atom attached to it and 3 others have four atoms attached to them (one atom with three others attached). The two that are at the end of the edge that belongs to both rings have no atoms attached, and the final of the 9 also has no atom.]
:Caption: Chemist
:Cueball: 10<sup>21</sup> in the caffeine alone

{{comic discussion}}

[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Hairy]]
[[Category:Comics featuring Hairbun]]
[[Category:Comics featuring Cueball]]
[[Category:Food]]
[[Category:Math]]
[[Category:Chemistry]]
[[Category:Philosophy]]
[[Category:Physics]]

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Talk:3103: Exoplanet System

2658: Coffee Cup Holes