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Dec15-10, 01:09 PM
JDoolin you are misinformed, global Lorentz invariance only occurs in a flat spacetime.
For instance, I would recommend talking about how, within the gravitational pull of a planet, the rate of proper time is a function of the distance from the planet. My suggestion would be to say that in this region, we have a situation where somehow, the geometry seems to differ from Lorentz in some fashion, for it is in these local regions where we find space-time to be curved. The particle, traveling on a straight path in its own coordinates, ends up traveling on a curved path in another body's coordinates. I think that the theory behind General Relativity is strong enough, that it does not need to rely on ambiguously defined terms and attacking the fundamentals of Special Relativity. It should stand constructively on its foundations--not try to dismiss them as "only valid locally." On the global level, such slowing of proper time (implicit in general relativity) won't make a difference, because the end result, from a gloabl perspective, is just the local slowing of the speed of light. It's no more paradoxical than having glass, with its index of refraction slowing the speed of light.
Sorry but this is wrong.
But claiming that physics is somehow "locally lorentz" implies that physics is not "globally lorentz."
Which is the case.
In curved spacetime there is no global Lorentz invariance, there is only Lorentz invariance at the local level.