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arXiv · astro-ph/0310344

Cosmological acceleration, varying couplings, and Lorentz breaking

Orfeu Bertolami·Ralf Lehnert·Robertus Potting·Andre Ribeiro
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Abstract

Many candidate fundamental theories contain scalar fields that can acquire spacetime-varying expectation values in a cosmological context. Such scalars typically obey Lorentz-violating effective dispersion relations. We illustrate this fact within a simple supergravity model that also exhibits the observed late-time cosmological acceleration and implies varying electromagnetic couplings.

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Orfeu Bertolami, Ralf Lehnert, Robertus Potting, Andre Ribeiro. 2003-10-14. Cosmological acceleration, varying couplings, and Lorentz breaking. https://doi.org/10.1103/physrevd.69.083513

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