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arXiv · 1007.2594

Coupling the inflaton to an expanding aether

William Donnelly·Ted Jacobson
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Abstract

We consider a Lorentz-violating theory of inflation consisting of Einstein-aether theory with a scalar inflaton coupled bilinearly to the expansion of the aether. We determine the conditions for linearized stability, positive energy, and vanishing of preferred-frame post-Newtonian parameters, and find that all these conditions can be met. In homogeneous and isotropic cosmology, the inflaton-aether expansion coupling leads to a driving force on the inflaton that is proportional to the Hubble parameter. This force affects the slow-roll dynamics, but still allows for a natural end to inflation.

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William Donnelly, Ted Jacobson. 2012-01-16. Coupling the inflaton to an expanding aether. https://doi.org/10.1103/physrevd.82.064032

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