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arXiv · 0903.0986

Cosmological solutions of emergent noncommutative gravity

Daniela Klammer·Harold Steinacker
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Abstract

Matrix models of Yang-Mills type lead to an emergent gravity theory, which may not require fine-tuning of a cosmological constant. We find cosmological solutions of Friedmann-Robertson-Walker type. They generically have a big bounce, and an early inflation-like phase with graceful exit. The mechanism is purely geometrical, no ad-hoc scalar fields are introduced. The solutions are stabilized through vacuum fluctuations and are thus compatible with quantum mechanics. This leads to a Milne-like universe after inflation, which appears to be in remarkably good agreement with observation and may provide an alternative to standard cosmology.

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Daniela Klammer, Harold Steinacker. 2009-06-10. Cosmological solutions of emergent noncommutative gravity. https://doi.org/10.1103/physrevlett.102.221301

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