Unimodular cosmology and the weight of energy
arXiv:hep-th/0702184 · doi:10.1103/PhysRevD.76.064013
Abstract
Some models are presented in which the strength of the gravitational coupling of the potential energy relative to the same coupling for the kinetic energy is, in a precise sense, adjustable. The gauge symmetry of these models consists of those coordinate changes with unit jacobian.
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