ar X iv : a st ro - p h / 03 08 13 5 v 2 1 7 Se p 20 03 Acceleration parameter of the Universe expansion and cosmological equation of state
نویسنده
چکیده
We analyze the astronomical data on the explosions of supernovae Ia as well as the precision measurement of cosmic microwave background in order to get a model-independent determination of the acceleration parameter for the Universe evolution. The effective parameter of state in the cosmological equations, which gives the ratio of pressure to the energy density, as shown, can naturally get the values less than-1, if one introduces a nonzero mass of the graviton in the framework of relativistic theory of gravitation (RTG). We demonstrate the model equivalence of evolution equations for the flat homogeneous isotropic universe in the general relativity to those of RTG. Some constraints on the graviton mass value are obtained.
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