2898: Orbital Argument

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Orbital Argument
"Some people say light is waves, and some say it's particles, so I bet light is some in-between thing that's both wave and particle depending on how you look at it. Am I right?" "YES, BUT YOU SHOULDN'T BE!"
Title text: "Some people say light is waves, and some say it's particles, so I bet light is some in-between thing that's both wave and particle depending on how you look at it. Am I right?" "YES, BUT YOU SHOULDN'T BE!"


In this comic, White Hat is using the middle ground fallacy to try to make a compromise between the positions of Cueball and Megan.

Cueball appears to be asserting a geocentric viewpoint, whilst Megan adheres to a heliocentric one, both of which are flawed descriptions of the way things are, but the latter is much closer to reality. White Hat, however, considers it politic to 'split the difference' and declares his intention to compromise with a 'middle' option, to try to uncritically please both parties. (Though it's probable that he may instead just equally annoy them both!)

On a naive reading, which imagines a point of common orbit midway between the bodies, his thesis is simply wrong. However, by one way of looking at it, it happens that he is also correct. Because two bodies exert equal but opposite gravitational forces on each other, each orbits around the average location of the other, and therefore they both orbit a common center. This barycenter is located somewhere between the centers of mass of the two bodies; the distance of each body's center of mass from the barycenter is proportional to the other body's mass. This is most apparent in systems where the two bodies have similar masses, but it is present to an extent in all orbital pairs, even when one body is far more massive than the other. For this reason, Earth does not orbit the center of the stationary Sun as described by the heliocentric model. However, the Earth-Sun barycenter is only slightly different from the Sun's own true center, still well within the Sun. It is around this which the Sun wobbles, in contrast to the way the Earth orbits around this unequally proportioned midpoint.

That White Hat has worded his compromise solution in a way that (arguably) encompasses the deeper truth of the barycentric viewpoint is not treated as justifying his mediating approach. It is clearly understood, by someone who seems to understand the complexities (e.g. a NASA physicist) that White Hat's 'successful' conclusion is just accidental, and such a person may therefore find this vexatious. This seems to be a case of a Gettier problem: White Hat reaches a true statement via unjustified logic.

The title text extends the principle of the comic's astronomical viewpoint down to the correspondingly opposing 'quantum world'. For various well-studied reasons, light is often described either as particles or as waves. White Hat's approach would be to give both viewpoints equal credit and suggest a compromising middle-ground explanation. In this case, also, he would have the correct answer but, in the continuing view of an increasingly exasperated witness to his chronic "half-and-half"ism, not through a logical proof. Averaging predictions of experts is used to reliably improve the accuracy of the ensemble, as well as other methods that might produce a consensus forecast, so his heuristic may indeed have some validity for some types of prediction along a continuum of possibilities. But, for this case, two opposing philosophical positions do not represent the right kind of data to merge into a balanced 'best fit' intermediate predictive model.

Another example of the middle ground fallacy was used in 690: Semicontrolled Demolition, although in that case the person offering the compromise solution was not portrayed as getting the right answer by accident.

Orbits of celestial bodies are quantified using a set of parameters called orbital elements. Some of these parameters are commonly known as arguments, such as the Argument of periapsis. However, these kind of arguments tend to lead to consensus rather than disagreements. Independent measurements of the arguments might indeed be combined by taking the mean (to discover the middle ground).

The Earth-Moon barycenter is located approximately ¾ of the way from Earth's center of mass to its surface, towards the Moon's center of mass. The equivalent Jupiter-Sun barycenter, meanwhile, is located just above the 'surface' of the Sun due to the masses involved being not as different (but still significantly so), and the much greater distance between them. Pluto-Charon barycenter is located completely outside of Pluto, in part because they are much more similar masses, and are thus considered to orbit each other (tidally locked) around a point approximately 5.4% along the distance between the surfaces of Pluto surface and Charon, or 11% of their center-to-center distance.

As each of the planets and the Sun are simultaneously orbiting/'being orbited' (and every planet also measurably pulls on every other, etc, even discounting every smaller and/or more distant body in the universe), the combined solar-system's barycenter is a less simply-defined point (that being more likely to be within the Sun, at any given point of time), which can often be considered to more simply average out to "<each planet> orbits the Sun" for most purposes.


[From left to right, Cueball, White Hat and Megan standing. Cueball and Megan are arguing. Cueball is raising a finger while Megan's arms are outstretched. White Hat stands between them, both hands out in an equivocal gesture.]
Cueball: The sun orbits the earth!
Megan: The earth orbits the sun!
White Hat: When two people disagree, the truth is always somewhere in the middle. Maybe the earth and the sun orbit a common center!
[Caption below the panel:]
It's annoying when people are right by accident.
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May not be (probably isn't!) the inspiration for this comic, but just yesterday there was news of the latest successes in cooling down Positronium (an 'atom' in which nothing is at the nucleus, the charges 'orbit each other' (or the quantum equivalent)). A co-inky-dink, surely, but just thought I'd mention it in passing... 03:13, 24 February 2024 (UTC)

In editing, I'm accutely aware that even the "relatively small" force by the Earth on the Sun is a bad way of putting it. Looked at properly, exactly the same force is exerted against the Sun by the Earth (heavy item drawn pulled down to light item) as is exerted against the Earth by the Sun (lighter item being pulled down by heavier item). ((Fairly easily proven, these days: e.g. If it were not so, something like a bowling-ball and ping-pong ball could be kept separate by a stick, but released in space where they'd then work as a 'gravity drive' that propelled them one way (or perhaps the other!) without any need for power/propellant.)) Of course, the force should be considered equal (bidirectionally singular) with the inertial framing being the factor that makes the freefalling apple the more obvious thing to fall than the Earth upon which any budding Newton is stood/sat in rapt observation. But the Earth's contribution to the (currently) indivisible joint attraction that drives both sides of any 2-body problem is far more than any given apple and far less than any given star. As and when we can perhaps split this (either directionally 'diode' the flow of gravitational effects, or even independently manipulate inertial and gravitational masses) then perhaps we will need to be more discriminating in calculating/describing about such things. Assuming we don't just go with "gravity is a lie, it's all just mass-curved spacetime", instead. ;) But just thought I'd expound a few different relevent worldviews, of greater or lesser usefulness... 04:35, 24 February 2024 (UTC)

Atomic & subatomic "particles" as discrete units, are a test condition artifact. Everything is waves. ProphetZarquon (talk) 13:56, 24 February 2024 (UTC)

Or (admitedly 'wavy') strings. Or resonant fields. Or some other esoterically theorised GUT-fodder... ;) 15:49, 24 February 2024 (UTC)
Submolecular strings are just (helical) waves viewed through a threshold-conditional gate.
ProphetZarquon (talk) 21:34, 24 February 2024 (UTC)

I think comic 690: Semicontrolled Demolition is relevant to this one and should appear somewhere in the explanation of this one, as it touches on the same base idea. 15:45, 24 February 2024 (talk) (please sign your comments with ~~~~)

Isn't there something about knowledge being true information arrived at by logically sound reasoning? This meets the first criteria but not the second. RegularSizedGuy (talk) 17:31, 25 February 2024 (UTC)

I feel there is an additional explanation that White Hat did not intend. The Sun and Earth, the entire Solar system for that matter, orbits the center of the Milky Way Galaxy. Which may also orbit the center of the known Universe? I am not an astrophysicist or knowledgeable enough to attempt a proper explanation. Vampire (talk) 15:31, 26 February 2024 (UTC)

"The Earth-Moon barycenter is located approximately ¾ of the way from Earth's center of mass to its surface, towards the Moon's center of mass. Our tidal bulges (oceanic and otherwise) occur along that line. One bulge is towards the Moon because of the gravitational attraction, and the other is in the opposite direction, by centrifugal force from the Earth's rotation around the barycenter." This is wrong for a couple of reasons. First, both bulges are the result of the same effect, and they would be there even if the Moon and Earth weren't producing centrifugal force by rotating about each other. In the usual explanation of the opposite bulges, you look at the acceleration of a particle on the near side of the Earth towards the Moon by more, the acceleration of the center of the Earth by a medium amount, and the acceleration of a particle on the far side of the Earth by less. Then, to look at things in the frame of reference of the center of the Earth, you subtract the center's acceleration, and find that the near side accelerates toward the Moon by a little, and the far side accelerates away from the Moon by a little. But even that explanation is wrong, or at least, very incomplete - the main driver of the tides is due to the vastly larger volume of water *away* from the line through the Earth's and Moon's centers; when you do that same vector subtraction of the local acceleration from the Moon minus the acceleration of the center of the Earth, you find that you get a tangential component of acceleration, and since water can flow, it does, until it reaches a surface of constant potential (it's not a lot of distance, but it's a lot of volume moving, so the tidal bulge is a significant volume of water). See https://web.archive.org/web/20220115060446/https://www.lockhaven.edu/~dsimanek/scenario/tides.htm 15:46, 26 February 2024 (UTC)

Ok, so regarding this argument, the problem is removing the clarification that this is not subject to consensus 'averaging'. Two totally different opinions which cannot be averaged, merged, subsampled or intermingled. It is maybe useful to mention taking multiple weather predictions and generating the most supported trend, much as natural language processing algorithms, but here the two statements cannot be combined in simple numerical or tokenwise ways (that is the point). Yes, state that mid-point estimations are useful (I'm happy with such a statement, and preserved/enhanced it), but do not remove the salient issue that in this case it is not a useful process. It's beyond even 2893: Sphere Tastiness illogic. Which is the joke.... 18:51, 28 February 2024 (UTC)

Re: expert averaging, it's non-intuitive to consider that different symbolic statements in text can be averaged, but with a neural predictive model (NN, human brain) this actually is possible. You *can* average the latent vector representations of two text inputs (x,x') in the (vectorized) latent space of a neural model (z + z'). Latent averaging is often used in ML as an empirical heuristic to improve performance (sentence embeddings, mixture-of-experts models), and can be hypothesized to operate via the mechanism of improving the efficiency of a learned Bayesian circuit that performs abductive reasoning. Averaging is more obviously seen in the output token space, for example, you might symbolically average temperatures from two weather models (formalized as ensemble models, consensus models, etc.). So although it sounds weird at first glance, averaging experts in either latent or manifest space is often a good heuristic for a guess, and is rewarded as a result. Arguably, White Hat is using this algo and actually making a good guess here, although if he can't explain his thought process symbolically (he's just doing it because it feels "nice"), his accuracy may come off as an "accident." Caveats: there are definitely conditions under which averaging experts can go awry in both latent and manifest spaces (false balance, non-expert data, partial observability, etc.), but this arguably isn't the case in either the orbital or wave-particle initial observations. 01:21, 29 February 2024 (UTC)