Talk:Bible says the sun goes around the earth
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The 'See For Yourself' section of this page is wrong. The Foucault pendulum will not demonstrate whether the sun is revolving around the Earth or vice versa. It only demonstrates that the Earth is rotating on its axis which could be true in either a heliocentric or geocentric model.
- Actually, the Geocentric model states that the Earth is fixed in place at the center of the Universe, and does not rotate.--Mr A. 16:53, 19 February 2008 (UTC)
I refer you to the www.wikipedia.com page on this subject, section "Geocentrism and rival systems":
"Not all Greeks agreed with the geocentric model. The Pythagorean system has already been mentioned; some Pythagoreans believed the Earth to be one of several planets going around a central fire. Hicetas and Ecphantus, two Pythagoreans of the 5th century BC, and Heraclides Ponticus in the 4th century BC, believed that the Earth rotated on its axis but remained at the center of the universe. Such a system still qualifies as geocentric."
http://en.wikipedia.org/wiki/Geocentric
Geocentric does not imply anything about the rotation of the Earth. Regardless, referring to the Foucault Pendulum experiment as a method for empirically refuting that the "sun goes around the earth" is wrong. --Krispyos 03:07, 20 February 2008 (UTC)
- It is wrong as a method for refuting that the sun goes around the earth once per year.
- It is not wrong as a method for refuting that the sun goes around the earth once per day.
- Once-per-year geocentrism with a rotating Earth may be geocentrism, but it is non-standard geocentrism - it is the first step in the direction of heliocentrism. Tycho Brahe's model, with the Sun going round the Earth and the other planets going round the Sun, is the second step.
- Both intermediate steps have been unpopular because they combine the drawback of the heliocentric system ("what? the Earth rotates? I don't feel any movement!") with the drawback of the geocentric system (arbitrary system of reference with large masses swinging around small ones).
- So what do we do now? --tk 13:13, 20 February 2008 (UTC)
- It is not wrong as a method for refuting that the sun goes around the earth once per day.
I do not follow you. The pendulum tells you nothing about the relative positions of the sun and the Earth. The Earth could be rotating in place with the sun orbiting it and the pendulum would still work as expected.
If you say that your "standard" geocentric model is one where the Earth must not be rotating (which again, is only a subset of geocentric models), then you can at least show part of the geocentric theory to be wrong with the Foucault pendulum experiment, among others. The title of this page though does not suggest a non-rotating Earth, nor does the content define geocentric to mean a system where the Earth is both the center and not rotating. Even if you included the old section on the Foucault pendulum, the page would have to be updated with more precise language and terminology and the "See for Yourself" section would have to be refined so as not to imply that the Foucault pendulum alone is enough to contradict the geocentric model.
If you want to talk about how the Foucault pendulum is evidence against the Biblical claim that the Earth is motionless then that is a different subject altogether. Perhaps the title of the page should be changed? --Krispyos 16:39, 20 February 2008 (UTC)
- Look, the entire evidence that "The Sun goes around the Earth" that they had was the apparent motion of the Sun in the sky. The Foucault Pendulum shows that the earth rotates once per day. This explains the Sun's apparent motion right there. I'm not sure how precise their measurement was, but the pendulm demonstrates exactly that what you are seeing in the Sun's motion is not the result of it moving, it's the result of the Earth moving. If their measurements are precise enough, they can even see that the pendulum DOES show the there is motion relative earth/sun because the pendulum takes 4 minutes less to complete it's circle than the length of the day. The pendulum won't tell you whether that motion is the Earth around the Sun or the Sun around the Earth, but it screws with literalism right there, the apparent motion of the sun is PRIMARILY caused by the rotation of the Earth.
- Once you've accepted that the motions seen are only apparent, the rest falls into place. The "it's obviously true" argument falls apart instantly and the solar system just makes more sense sun-centered.
- --Suttkus 23:42, 20 February 2008 (UTC)
"If their measurements are precise enough, they can even see that the pendulum DOES show the there is motion relative earth/sun because the pendulum takes 4 minutes less to complete it's circle than the length of the day."
The change in angle of the plane of oscillation for the pendulum is a function of the pendulum's latitude. The angular change for one day is determined by -2 pi sin ( latitude ). Therefore, the time it takes for the pendulum to "complete its circle", or for the plane of oscillation to complete one full rotation depends on where you are geographically located. This could be true in a system where the sun rotated around the Earth, or even in a system where both the sun and the Earth were rotating around their own axis but in relative stationary positions. Also, at the equator, no significant change in the plane of oscillation will be observed at all, so it wouldn't do the people in Ecuador much good to observe the pendulum's motion. In fact, they might very well arrive at the incorrect conclusion.
The impression I received from this page is that the "See for yourself" section is presenting the Foucault pendulum experiment as a necessary and sufficient justification for assuming the Earth orbits the sun and not the other way around. Maybe I am wrong on this, but I am certainly not convinced. --Krispyos 05:50, 21 February 2008 (UTC)
