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Renormalized Stress Tensor for trans-Planckian Cosmology

D. Lopez Nacir·F. D. Mazzitelli·C. Simeone
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Abstract

Finite expressions for the mean value of the stress tensor corresponding to a scalar field with a generalized dispersion relation in a Friedman--Robertson--Walker universe are obtained using adiabatic renormalization. Formally divergent integrals are evaluated by means of dimensional regularization. The renormalization procedure is shown to be equivalent to a redefinition of the cosmological constant and the Newton constant in the semiclassical Einstein equations.

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D. Lopez Nacir, F. D. Mazzitelli, C. Simeone. 2005-12-16. Renormalized Stress Tensor for trans-Planckian Cosmology. https://doi.org/10.1103/physrevd.72.124013

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