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arXiv · 1907.02974

Ricci cosmology

Rudolf Baier·Sayantani Lahiri·Paul Romatschke
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Abstract

We revisit spatially flat FLRW cosmology in light of recent advances in standard model relativistic fluid dynamics. Modern fluid dynamics requires the presence of curvature-matter terms in the energy-momentum tensor for consistency. These terms are linear in the Ricci scalar and tensor, such that the corresponding cosmological model is referred to as ``Ricci cosmology''. No cosmological constant is included, there are no inflaton fields, bulk viscosity is assumed to be zero and we only employ standard Einstein gravity. Analytic solutions to Ricci cosmology are discussed, and we find that it is possible to support an early-time inflationary universe using only well-known ingredients from the Standard Model of physics and geometric properties of space-time.

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Rudolf Baier, Sayantani Lahiri, Paul Romatschke. 2019-07-05. Ricci cosmology. https://arxiv.org/abs/1907.02974

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