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arXiv · 1511.07450

Quantum Cosmology Near Two Dimensions

Teresa Bautista·Atish Dabholkar
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Abstract

We consider a Weyl-invariant formulation of gravity with a cosmological constant in d-dimensional spacetime and show that near two dimensions the classical action reduces to the timelike Liouville action. We show that the renormalized cosmological term leads to a nonlocal quantum momentum tensor which satisfies theWard identities in a nontrivial way. The resulting evolution equations for an isotropic, homogeneous universe lead to a slowly decaying vacuum energy and a power-law expansion. We outline the implications for the cosmological constant problem, inflation, and dark energy.

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Teresa Bautista, Atish Dabholkar. 2015-11-23. Quantum Cosmology Near Two Dimensions. https://doi.org/10.1103/physrevd.94.044017

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