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arXiv · 0803.0181

On the energy of homogeneous cosmologies

James M. Nester·Lau Loi So·T. Vargas
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Abstract

An energy for the homogeneous cosmological models is presented. More specifically, using an appropriate natural prescription, we find the energy within any region with any gravitational source for a large class of gravity theories--namely those with a tetrad description--for all 9 Bianchi types. Our energy is given by the value of the Hamiltonian with homogeneous boundary conditions; this value vanishes for all regions in all Bianchi class A models, and it does not vanish for any class B model. This is so not only for Einstein's general relativity but, moreover, for the whole 3-parameter class of tetrad-teleparallel theories. For the physically favored one parameter subclass, which includes the teleparallel equivalent of Einstein's theory as an important special case, the energy for all class B models is, contrary to expectation, negative.

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James M. Nester, Lau Loi So, T. Vargas. 2008-03-23. On the energy of homogeneous cosmologies. https://doi.org/10.1103/physrevd.78.044035

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