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Physics Related with Co-moving Coordinate System

Ding-fang Zeng
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Abstract

We derive the metric of an expanding universe with zero accelerations by pure kinematic method. By doing so we expatiate physics related with co-moving coordinate system in details. The most important discovery or our study is, in an expanding universe with zero accelerations, the red-shift of photons from distance galaxies is determined by the co-moving coordinate of the source galaxy instead of the scale factor's time dependence. Our discovery is consistent with the current observed super-novaes's luminosity-distance v.s. red-shift relations.

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Ding-fang Zeng. 2005-07-29. Physics Related with Co-moving Coordinate System. https://arxiv.org/abs/gr-qc/0506138

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