2640: The Universe by Scientific Field

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The Universe by Scientific Field
The math and philosophy people also claim everything, but the astronomers argue that the stuff they study really only comprises a small number of paper surfaces.
Title text: The math and philosophy people also claim everything, but the astronomers argue that the stuff they study really only comprises a small number of paper surfaces.


Astronomy is the study of outer space and celestial phenomena. This comic makes a joke that most of the "universe" falls under the study of astronomy, which makes sense because it is so vast and large and is not studied directly by other fields of science.

The volume of the observable universe is 3.566×1080 cubic meters. The volume of Earth is 1.08321×1021 cubic meters. 1.08321×1021 m3 ÷ 3.566×1080 m3 × 100% ≈ 3×10-58%, which is scientific notation for the second of the two percentages, the first being its difference from 100%.

Thus, the universe is comprised almost entirely of the objects of astronomical study, when measured by volume. There are many arguments to be made that this is not the most useful way of measuring the size of scientific fields compared to the universe. Other arguments include:

  • Astronomers are only studying the observable phenomena (i.e. light, subatomic particles, and gravity) of the rest of the universe, leaving the vast majority of the universe's properties (for instance the geology and biochemistry of an unknown planet in a distant galaxy) entirely unstudied.
  • Astronomy is only possible due to understanding of physics, optics, chemistry, mathematics, and geometry, so surely they deserve some credit.
  • The interesting parts of the universe are not the empty space.
    • They are the matter and energy described by physics and chemistry.
    • They are the life experiences of people, which are overwhelmingly terrestrial even for professional astronomers (who often complain about how little time they can allocate to making actual astronomical observations).
  • It is disingenuous to claim to be studying more than every other field when astronomy and astrophysics publications amount to only about 0.5% of academic science and engineering output worldwide.[1] Other fields may be studying smaller things, but they are studying them much more thoroughly.
  • Emptiness has less information and is less interesting than non-emptiness; therefore geometric volume is only very weakly correlated with useful information.

A counterargument is that astronomy, cosmology, and astrophysics are the only scientific disciplines that study the Big Bang and subsequent inflation from which all matter, energy, and space itself arose. The ordinary laws of physics can describe neither of those events.

The title text says that mathematicians and philosophers claim that what they study also represents everything. But (according to the comic) astronomers counter this by saying that they just study things that are written down, and this comprises just tiny amounts of "paper" on the Earth. This claim by mathematicians also appears in 435: Purity. A conceivable counterargument by philosophers could be that any and all science, including astronomy, is nothing more than a branch of epistemology, the philosophical study of knowledge. Another could be that since philosophy includes theology, it is studying something even larger than the universe (although one could argue back that theology is nothing more than writing fiction, and yet again just a study of pieces of paper.)


The Universe by Scientific Field
[A pie chart is shown. It is white except for a single black line going from the edge of the circle to the middle.]
Astronomy [The white space]
Other [The black line]

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I have a feeling reproductions of this particular XKCD will be popular on the doors of many offices in astronomy departments around the world. A bit like Gary Larson's Far Side cartoons are found everywhere in biology departments.

I just discovered Safari's "Live Text" feature. It allowed me to copy the numbers with all the digits, so I don't have to count them to create the transcript. But then someone else beat me to creating it. Barmar (talk) 22:44, 1 July 2022 (UTC)

I wonder if we should mention the area of telescope apertures compared to, say, the surface area of all laboratory glassware or something like that. Too much of a stretch? 23:18, 1 July 2022 (UTC)

“Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.” ― Douglas Adams, The Hitchhiker's Guide to the Galaxy -- 00:40, 2 July 2022 (UTC)

Agreeing with the argument in the current version of the explanation as I write: it is really, really hard to argue that astronomy covers more than physics, which lays claim to including all the physical sciences as subfields. Also, is "field" a pun on the force fields of ... physics? Nitpicking (talk) 03:32, 2 July 2022 (UTC)

I don't think most chemists would say that they're in a sub-field of physics, but chemistry is a huge part of astronomical spectroscopy. Similarly mathematicians relative to trigonometry. 03:47, 2 July 2022 (UTC)

There's a bit of a problem here. Yes, Astronomy is the study of pretty much anything that isn't Earth. But the other part is pretty much limited to studies of life on earth (biology excluding exo-/astrobiology as well as pretty much all branches of social sciences), studies of earths atmosphere (meteorology and related fields), studies of earths water (e.g. hydrology as well as aspects of biology and others), studies of earths lithosphere (terrestrial geology and subfields) and various tangential branches thereof (like studies of earth's past - as part of pretty much any subject mentioned before). Fields like physics (pretty much everything "real", i.e. 100%), chemistry (any condensed matter) or geology (any rocky bits) have claims to various (already "taken") parts of the universe. Mathematics and philosophy (mentioned in alt text) don't have a claim to much of anything "real" in the universe (except maybe the pieces of data storage (paper, brain, digital) used) but have a claim to all of the (not "real, I guess) sciences mentioned before. Of course, that makes them subject to, at least, physics, chemistry, biology and social (including historical) sciences in turn. - - - TL/DR: I seem to be in a bit of a mood to kill jokes today. 13:16, 2 July 2022 (UTC)

of course to continue the joke, while all those fields may have applicability beyond earth, the vast majority of what they actually study is ON earth (although to make the stretch, you have to consider any field that studies things off earth as a subset of astronomy, which would make for many very angry scientific debates... hmmm... science thunderdome, I kinda like this idea =D 15:05, 2 July 2022 (UTC)
Don't feel bad. The entire second half of the explanation at present is devoted to casting the joke as absurdist exaggeration and hyperbole. 15:30, 2 July 2022 (UTC)

Maybe the idea of the comic is that the diagram was created by astronomers to justify their existence, which explains the bias. Many lay people wonder why we spend so much money studying "out there" when there are so many problems here that could use the money (never mind that the fraction of government budgets devoted to astronomy is miniscule, and some of the discoveries do have terrestrial uses, particularly regarding climate change). And as alluded in the title text, other researchers could probably make a similar diagram that emphasizes their discipline. Barmar (talk) 17:01, 2 July 2022 (UTC)

Climate change? Only thing astronomy can tell us about climate change is where to move to when we inevitably destroy Earths climate. -- Hkmaly (talk) 01:03, 3 July 2022 (UTC)
The greenhouse effect was originally described in terms of albedo when the absorption spectra of CO2 was first characterized, but I can't think of any other examples. 01:16, 3 July 2022 (UTC)
Solar astronomy tells us what contributions are made by the sun and it's various cycles, general astronomy gives us orbital and therefor seasonal modifiers on that, both of which can then be accounted for to determine both local contribution, and expected trend changes. Further it gives both examples of what various conditions can result in (venus and mars especially) and even possible useful modifications we can make (eg solar shades for reducing, and reflectors for increasing solar effects, albedo modification for either). Not to mention minor things like knowing if a country sized rock might ruin our day --Not an Astronomer 15:54, 3 July 2022 (UTC)

There should be a large proportion for "Dark Knowledge" to imitate those astronomical summaries that try to emphasise how much of the universe is dark matter and/or energy 01:38, 3 July 2022 (UTC)

As to the alt text, you also have Max Tegmark, a physicist at MIT, who believes the entire universe is literally made of mathematics: Mathematical universe hypothesis. 06:54, 3 July 2022 (UTC)

Could be... although just like Holographic Theory, and to some degree Simulation Theory we'd be hard pressed to tell a difference. As long as the rules are consistent, and resist self modification, there's nothing to say the experience from the inside is any different between, physical, simulation, holographic, or mathematical realities. Hard to know which box you're in if you can't look outside it to confirm what the walls are made of 15:54, 3 July 2022 (UTC)
Quite true. Almost all of those "theories" aren't falsifiable, and therefore are technically metaphysics instead of genuine science. 22:24, 3 July 2022 (UTC)
Oh, absolutely. But it's definitely been made fun of by webcomics before, e.g. by: SMBC, so it's not outside the realm of possibility Randall may have meant that. 02:20, 5 July 2022 (UTC)
SMBC is a great comic. I wonder why it doesn't have an explanation wiki. 03:14, 5 July 2022 (UTC)
It's inexplicable...
 :) 11:45, 5 July 2022 (UTC)

I deleted this sentence from the explanation: "If we measure the universe by mass-energy instead, for example, the study of physics becomes non-trivial." I was planning to put an {Actual citation needed} tag on it, but it seemed to break up the explanation in an odd way, inside a paragraph front of a group of bullet points making similar arguments, so I'm moving it here for discussion instead. 17:33, 25 August 2022 (UTC)