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Hyperacute Interdynamics

|< < Prev #3178 (December 8, 2025)

Title text: Our models fall apart where the three theories overlap; we're unable to predict what happens when a nanometer-sized squirrel eats a grapefruit with the mass of the sun.

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Explanation

This is incomplete: This page was created BY A STAR WITH THE MASS OF A SQUIRREL. Don't remove this notice too soon. If you can fix this issue, edit the page!

Miss Lenhart is teaching a class, a recurring theme on xkcd. She correctly describes two of the three pillars of physics: general relativity, concerning very large objects, and quantum mechanics, concerning very small objects. The third pillar is thermodynamics, but she replaces this with the fictional hyperacute interdynamics, which supposedly specifically covers objects 10-30cm (~4" - ~12") in size and 200-700g (0.44lb - 1.54lb) in mass.

When a student points out that the application of hyperacute interdynamics is quite limited, Miss Lenhart responds by stating that this is made up for by the fact that it is apparently very accurate and precise, and gives examples of how it is able to perfectly describe squirrels and grapefruit, two objects which fit the necessary size and weight specifications (though see below). Her comment that there are hopes to unify this system with the other two reflects the efforts of physicists to unify general relativity with quantum mechanics, so far without success.

The title text extends the riff on unification, noting that, under the current system, measurements which require elements from all three pillars are impossible. The example given — when a nanometer-sized squirrel (covering quantum mechanics and hyperacute interdynamics) eats a grapefruit with the mass of the sun (once again covering hyperacute interdynamics and general relativity) — would cover all three domains. Such objects do not occur in real life^{[citation needed]}, so it is unknown how or why scientists would be trying to measure them.

The Eastern Gray Squirrel, which is the most prevalent squirrel in Massachusetts (where Randall lives), measures 16-20 inches (approx. 40-50 centimeters) on average when fully grown — outside the range of sizes given for hyperacute interdynamics to apply. It does, however, weigh between 400 and 600 grams — within the weight range. Whether hyperacute interdynamics would apply, then, would appear to depend on whether the 'and' in Miss Lenhart's statement is inclusive or exclusive. Also, the head-and-body size and the tail size of the Eastern Gray Squirrel are each individually within the hyperacute effective size (though potentially not mass), so if they were modelled individually or if the squirrel curled up then it would be able to be effectively modelled by hyperacute interdynamics This fshows the absurdity of Hyperacute Physics, with such a strict cutoff making it easy for objects to enter and exit the Hyperacute effective size, as opposed to relativity or quantum mechanics which slowly become worse at describing reality as size increases/decreases.

Additionally, some squirrels, such as the Borneo Black-Banded Squirrel do entirely fit into the Hyperacute effective size and mass

Transcript

[Miss Lenhart is teaching a classroom holding a finger up in front of the class. Two students can be seen sitting at desks in front of her, a Cueball like boy is on the first row and Jill, taking notes, is in the second row.]

Miss Lenhart: Modern physics rests on three main pillars:

General relativity, which describes very massive objects,

[Close up of Miss Lenhart.]

Miss Lenhart: Quantum Mechanics, which describes very small objects,

[In a frame-less panel the view zooms back out, but shows only Miss Lenhart.]

Miss Lenhart: and Hyperacute Interdynamics, which describes objects 10-30cm in size and 200-700g in mass.

[The panel zooms back in to a close up of Miss Lenhart.]

Student (off-panel): That last one seems kind of limited.

Miss Lenhart: Yeah, but over it's domain it's really precise. Absolutely nails squirrels and grapefruit.

Miss Lenhart: Someday we hope to unify it with the other two.

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Discussion

Make changes, try things out, or just have fun with the wiki here! Just leave everything above the line alone, please.

---

This is a test. PoolloverNathan^{[stalk the blue seas]} 20:48, 16 March 2021 (UTC)

This is not. —While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 10:29) 18:38, 17 November 2022 (UTC)

A foreign student asked me to help fight against his math teacher. That was unusual. He was in that class for just a couple of weeks. The teacher's phone number was sent to me. The student asked me to spam-call the teacher. 172.71.155.55 22:58, 18 September 2023 (UTC)

here i'm just messing around in html, ignore this

^furhhfghure _{guyrburgryhuyvfr} "rvhru"

interesting way of writing quotations xd

hmmm this one of putting "<p>" in a line break will come in handy for when i want it to start at the same place than the first line

Please beware that <p> on mediawiki also disables automatic paragraph breaks, so you need a closing </p> or you'll break automatic paragraph formatting for the rest of the page. Zmatt (talk) 22:06, 31 July 2024 (UTC)

edit: da hek did that "</div>" come from An user who has no account yet (talk) 14:14, 13 October 2023 (UTC)

hi uh its hard to get here. is this a reference to undocumented feature??? hmm... this is interesting.
108.162.241.216 02:05, 23 November 2023 (UTC)

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yum yum [citation needed]

Hiuiedeixgeyceiyedhcdiedcve {{trout}}

This is the leaderboard:

Last 7 days (Top 50)

Rank Score Pages Changes Username 1 5,747 5,725 5,849 DollarStoreBa'al 2 1,631 1,616 1,675 Victoria 3 22 18 22 TheusafBOT 4 13 4 25 Trimutius 5 11 7 11 Utdtutyabthsc 6 10 7 10 R128 7 7 4 7 Lp0 on fire 8 7 2 8 boB 9 6 3 6 Kivi Shapiro 10 6 3 5 Kynde 11 5 3 4 BunsenH 12 5 3 4 Headphones the stickman 13 4 2 3 Fephisto 14 4 4 4 KelOfTheStars! 15 4 1 3 Magtei 16 4 1 3 SammyChips 17 3 1 2 Paul 18 3 1 2 Beechmere 19 3 1 2 Logalex8369 20 3 1 2 Questioner 21 3 3 3 Batbrain55 22 3 1 2 Stephan Leeds 23 2 2 2 Qoiuoiuoiu 24 2 2 2 Theusaf 25 2 2 2 first last 26 2 2 2 ISaveXKCDpapers 27 2 2 2 August Fuller 28 2 2 2 Starnote 29 2 2 2 AgentMuffin 30 1 1 1 Kirinhatchi 31 1 1 1 Cobl703 32 1 1 1 CalibansCreations 33 1 1 1 Lallero 34 1 1 1 Sean McDonough 35 1 1 1 Heleatunda 36 1 1 1 EpicRedhead13 37 1 1 1 Planer28 38 1 1 1 DKMell 39 1 1 1 Darth Vader 40 1 1 1 SqueakSquawk4 41 1 1 1 I’m gonna fix this 42 1 1 1 XkUjlmoh 43 1 1 1 Michael Valler 44 1 1 1 Rory O’Kane 45 1 1 1 1234231587678 46 1 1 1 Daniel Griscom 47 1 1 1 Ictlogist 48 1 1 1 David Garfield 49 1 1 1 GreatWyrmGold

<a href=" [AT THE JULY 28TH MEETING][tab] "Cancel the meeting! Our cover is blown.">
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  Add comment        Create topic (use sparingly)       Refresh 

Discussion

Make changes, try things out, or just have fun with the wiki here! Just leave everything above the line alone, please.

---

This is a test. PoolloverNathan^{[stalk the blue seas]} 20:48, 16 March 2021 (UTC)

This is not. —While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 10:29) 18:38, 17 November 2022 (UTC)

A foreign student asked me to help fight against his math teacher. That was unusual. He was in that class for just a couple of weeks. The teacher's phone number was sent to me. The student asked me to spam-call the teacher. 172.71.155.55 22:58, 18 September 2023 (UTC)

here i'm just messing around in html, ignore this

^furhhfghure _{guyrburgryhuyvfr} "rvhru"

interesting way of writing quotations xd

hmmm this one of putting "<p>" in a line break will come in handy for when i want it to start at the same place than the first line

Please beware that <p> on mediawiki also disables automatic paragraph breaks, so you need a closing </p> or you'll break automatic paragraph formatting for the rest of the page. Zmatt (talk) 22:06, 31 July 2024 (UTC)

edit: da hek did that "</div>" come from An user who has no account yet (talk) 14:14, 13 October 2023 (UTC)

hi uh its hard to get here. is this a reference to undocumented feature??? hmm... this is interesting.
108.162.241.216 02:05, 23 November 2023 (UTC)

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

	Soup

yum yum [citation needed]

Hiuiedeixgeyceiyedhcdiedcve {{trout}}

This is the leaderboard:

Last 7 days (Top 50)

Rank Score Pages Changes Username 1 5,747 5,725 5,849 DollarStoreBa'al 2 1,631 1,616 1,675 Victoria 3 22 18 22 TheusafBOT 4 13 4 25 Trimutius 5 11 7 11 Utdtutyabthsc 6 10 7 10 R128 7 7 4 7 Lp0 on fire 8 7 2 8 boB 9 6 3 6 Kivi Shapiro 10 6 3 5 Kynde 11 5 3 4 BunsenH 12 5 3 4 Headphones the stickman 13 4 2 3 Fephisto 14 4 4 4 KelOfTheStars! 15 4 1 3 Magtei 16 4 1 3 SammyChips 17 3 1 2 Paul 18 3 1 2 Beechmere 19 3 1 2 Logalex8369 20 3 1 2 Questioner 21 3 3 3 Batbrain55 22 3 1 2 Stephan Leeds 23 2 2 2 Qoiuoiuoiu 24 2 2 2 Theusaf 25 2 2 2 first last 26 2 2 2 ISaveXKCDpapers 27 2 2 2 August Fuller 28 2 2 2 Starnote 29 2 2 2 AgentMuffin 30 1 1 1 Kirinhatchi 31 1 1 1 Cobl703 32 1 1 1 CalibansCreations 33 1 1 1 Lallero 34 1 1 1 Sean McDonough 35 1 1 1 Heleatunda 36 1 1 1 EpicRedhead13 37 1 1 1 Planer28 38 1 1 1 DKMell 39 1 1 1 Darth Vader 40 1 1 1 SqueakSquawk4 41 1 1 1 I’m gonna fix this 42 1 1 1 XkUjlmoh 43 1 1 1 Michael Valler 44 1 1 1 Rory O’Kane 45 1 1 1 1234231587678 46 1 1 1 Daniel Griscom 47 1 1 1 Ictlogist 48 1 1 1 David Garfield 49 1 1 1 GreatWyrmGold

<a href=" [AT THE JULY 28TH MEETING][tab] "Cancel the meeting! Our cover is blown.">
        Add comment