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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!"

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by an ARGUMENTATIVE ORBITAL ELEMENT - Please change this comment when editing this page. Do NOT delete this tag too soon.

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 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.

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.

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. 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, and Cueball is therefore least correct, and it would be a false solution to give his worldview an equivalence of validity.

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. Which is 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 actually correct reasoning.

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).

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[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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