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Isn't the whole historic Discussion of Heliocentric vs. Geocentric Worldview just about a Calculation-Technique. I mean I could also choose my coordinate-center to be in the middle of Earth and setup my differential Equations and starting points and it would still describe all Movements correctly, right?

Now if I want to solve this it might be pretty wise to choose the Sun as my coordinate origin. But nevertheless I could transform the resulting curve so that the origin is within earth and I can claim that the Sun is (in a fancy possibly self-intersecting way) rotating around Earth, and even the whole Universe is ( in a very fancy way) rotating around the Earth.

What's the Problem here? Isn't this the General Principle of Relativity in Physics?

How do we have to define Rotation, so that we get the Heliocentric Worldview? If we don't allow self-intersections, we would get a Problem with double-star-systems and Planets which rotate around both stars.

It seems that the current Definition relies on the Masses of the involved Objects. But this seems to be a very naive View neglecting the Fact that Forces aren't imposed by the "stronger" Object ( = Human Intuition) but that they are just caused by "Physics itself".


marked as duplicate by jinawee, Kyle Kanos, user10851, Brandon Enright, tpg2114 Feb 18 '14 at 5:13

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Actually the COM for the 2-body problem is the essential feature in this subject and with respect to it, both the Earth and the Sun rotate. Indeed, motion is relative, the relativity of it is even easier to understand in the Galilean Relativity than in Special Relativity.

The Heliocentric view is actually the correct opinion that the Sun of our planetary system can be taken as a geometric center of the whole 10 body system, as opposed to Earth (Geocentric view), up to finesses such as COM.

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    $\begingroup$ Just to corroborate this answer, note that the center of mass of the earth-sun system lies deep within the sun. $\endgroup$ – Jerry Schirmer Feb 17 '14 at 20:34

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