 Geocentrism Question

I understand that the theory of Geocentrism is being popularized by Robert Sungenis. I have a question, for people interested in this debate:

If Heliocentrism is true, then that means that all people living along the equator experience a certain centrifugal force. Considering the speed at which the Earth rotates, this may be very large. Now, if that person traveled to one of the poles, that person would experience no such centrifugal force, and he should feel much heavier.
My question is, is there such a force, and if there is, is its magnitude enough to account for the frequency of the Earth’s rotation?

The acceleration due to gravitation (g) is 9.78039 meter/second^2 at the equator and 9.83217 meter/second^2 at the poles.

Since 9.83217 / 9.78039 = 1.0053, objects weigh 0.53% heavier at the poles.

[quote=El Católico]I understand that the theory of Geocentrism is being popularized by Robert Sungenis. I have a question, for people interested in this debate:

If Heliocentrism is true, then that means that all people living along the equator experience a certain centrifugal force. Considering the speed at which the Earth rotates, this may be very large. Now, if that person traveled to one of the poles, that person would experience no such centrifugal force, and he should feel much heavier.
My question is, is there such a force, and if there is, is its magnitude enough to account for the frequency of the Earth’s rotation?
[/quote]

El Catolico,

Yes, there is indeed a difference between the gravitational accelerations at the equator and at the poles. There are two effects: first, there is the centrifugal force effect that you note, and second, there is the fact that the diameter of the earth at the equator is 26 miles greater than the diameter through the poles. This increased diameter at the equator is itself an effect of the centrifugal force caused by the rotation of the earth.

On top of this, one can use a Foucault pendulum to see the rotation of the earth directly. If the pendulum were placed at the north pole, it would oscillate in a constant plane in space as the earth rotated underneath it. The plane of the oscillation of the pendulum appears to make a full rotation once every twenty-four hours (actually a little less, to account for the difference between a solar and a siderial day). At lower latitudes the change of the plane of oscillation is slower; it can be calculated, and the actual Foucault pendulums do behave in the way that the heliocentric theory predicts.

While this is strong evidence in favor of the heliocentric theory (by which I mean the standard theory of cosmology, including the motion of the sun about the center of the galaxy), it is not evidence against geocentricism. The geocentric theory claims that the rotation of the distant stars and galaxies induces centrifugal forces identical in nature to the ones predicted by the standard theory in a rotating coordinate system. So every observation that supports the heliocentric theory also supports this geocentric theory.

In fact, in my opinion the only difference between the two theories is a coordinate transformation. Simply put, the coordinate system of the heliocentric theory is much easier to work with when dealing with cosmic motions than the coordinate system of the geocentric theory. My beef with the geocentricists is not that they claim that their theory is correct but that they claim that the standard cosmological theory is wrong.

• Liberian

So, is the increase in weight at the poles enough to account for both the centrifugal effect AND the increase in gravity? I mean, the speed at which we move relative to the axis must be enormous, since we do one rotation a day, and the circumference of the earth is quite large.

I have very little background in science so I am not the most proficient in these issues.

The radius of the Earth at the equator is 6378.5 km.

The angular velocity of the Earth is approximately 2pi/246060 second^-1, actually 2pi/23.93446966060 second^-1 taking the sidereal day into account.

Multiplying the radius times the angular velocity gives a rotation velocity of 465.13 meter/second at the equator relative to the center of the Earth (for the origin of the coordinate system) and the fixed stars (for the axes of the coordinate system).

The centrifugal acceleration is the rotational velocity squared divided by the radius, which works out to 0.034 meter/second^2.

Although IIRC isn’t it centripetal force?

Centrifugal force is only an effective force that is merely a manifestation of inertia.

[quote=Steve Andersen]Although IIRC isn’t it centripetal force?

Centrifugal force is only an effective force that is merely a manifestation of inertia.
[/quote]

Centrifugal force is a “fictional” (or “fictitious”) force that appears when you want to use Newtonian mechanics in a non-inertial coordinate system, such as the coordinate system in which the Earth isn’t rotating. The Coriolis force is another example of a “fictional” force.

The centripetal force in this case is 1g, resulting from the Earth’s gravity.

Hi Catholic 2003:

Any force that occurs in a rotating earth case should have an anaolg in the fixed earth case. You may want to read through this thread to get a perspective on this:

www.veritas-catholic.blogspot.com

Hi El Catolico:

Any force that occurs in a rotating earth case should have an analog in the fixed earth case. The following thread gives an example using Einstein’s General Relativity:

www.veritas-catholic.blogspot.com

[quote=El Católico]So, is the increase in weight at the poles enough to account for both the centrifugal effect AND the increase in gravity? I mean, the speed at which we move relative to the axis must be enormous, since we do one rotation a day, and the circumference of the earth is quite large.

I have very little background in science so I am not the most proficient in these issues.
[/quote]

That’s exactly right. The increase in gravity felt at the poles is just equal to the sum of the two effects.

The earth being about twenty-five thousand miles around at the equator, and making one rotation in twenty-four hours, a point on the equator is moving at just over a thousand miles per hour relative to the poles.

That sounds pretty fast, and it is, but in general things in space move even faster. A satellite in low earth orbit travels about the same distance in only an hour and a half, giving it a speed of about sixteen thousand miles per hour. And the earth in its orbit around the sun moves with a speed of eighteen and a half miles per second.

• Liberian
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