[geocentrism] Re: (no subject)
- From: RM Mentock <mentock@xxxxxxxxxxxxxx>
- To: geocentrism@xxxxxxxxxxxxx
- Date: Sun, 01 Aug 2004 09:07:59 -0400
At 06:55 AM 8/1/2004, you wrote:
>On 31 Jul, . <yerushabel@xxxxxxxxx> wrote:
> > As Moller's text on Relativity makes clear, the centrifugal, Coriolis
> > and Eulerian forces which are treated as fictitious forces in a
> > non-geocentric context are real, actual forces in a geocentric context.
>
> No they're not real. They seem to be real if you're in a rotating
>environment, but they don't actually exist.
In general relativity, even gravity is fictitious.
General relativity allows non-inertial frames of reference,
even earth-centered earth-fixed. Here's a quote from
Einstein:
"The struggle, so violent in the early days of science, between
the views of Ptolemy and Copernicus would then be quite
meaningless. Either CS could be used with equal justification.
The two sentences, 'the sun is at rest and the earth moves,'
or 'the sun moves and the earth is at rest,' would simply mean
two different conventions concerning two different CS."
-- Einstein and Infeld, The Evolution of Physics, p.212 (p.248
in original 1938 ed.)
CS, in that quote, means Coordinate System, and here's
another from Einstein's Theory of Relativity by Max Born.
From page 356 of the 1962 Dover edition:
"A similar error lies at the root of the following, which is
continually being brought forward, although the explanation is very
simple.
"According to the general theory of relativity, a coordinate
system which is rotating with respect to the fixed stars (i.e., which is
rigidly connected with the earth) is fully equivalent to a system which
is at rest with respect to the fixed stars. In such a system, however,
the fixed stars themselves acquire enormous velocities."
Born does provide the simple explanation promised. In the Earth-fixed
system, the metric coefficients are transformed, becoming very large at
large distances away from the Earth. Since the limit on the speed of
light is derived from these coefficients, the "enormous velocities" of
the stars are still less than their local speed of light.
Nowadays, the interpretation is different. At any place, one can
find a local frame of reference that can be aligned so as to be
inertial--and in *that* local frame, the local speed of light is c.
So, it is often said that even in general relativity, the speed of
light is restricted to c--but you can see that the interpretations
are a bit different.
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