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Old 02-09-2008, 01:53 PM
AGarvin
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AGarvin is offline
 
Join Date: Sep 2005
Posts: 100
I think your a bit confused Alex as to what both Einstiens and Newtons theories are actually saying.

GR is a geometric theory that describes how the presence of mass/energy, momentum etc ... affects the shape of said geometry. The theory uses a particular type of geometry (Riemannian geometry) that allows "space" to curve. However it IS NOT saying that space curves in the real physical sense, it is simply treating space as though it curves. This is a very important distinction to make. We don't even know what space physically is, we don’t have a theory to say what space physically is and therefore cannot say whether it can really physically curve or not. This misconception also appears when folks talk about "expanding space" in cosmology. A more accurate term is "expanding universe" as we cannot say whether space is really physically expanding either (GR uses the concept of comoving coordinates to describe what is often misleadingly termed expanding space). Both Newtonian mechanics and GR will arrive at the same results in cases of low gravitational potential, but one treats gravity as a force and the other treats it as a consequence of geometric curvature. So which is correct? Both are.

It is perfectly valid Alex for you to propose a theory that treats gravity as a "push" force, but your theory needs to provide the mathematical foundation that allows me calculate how fast a tennis ball will drop when I let it go, or what path my spacecraft will follow as I do a fly-by of Jupiter. I suspect however that what your suggesting is that gravity in the real physical sense is a push and I don’t think you realize the magnitude of such a statement.

Andrew.

Last edited by AGarvin; 02-09-2008 at 04:12 PM.
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