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Order reduction in semiclassical cosmology

Grazyna Siemieniec-Ozieblo·Andrzej Woszczyna
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Abstract

We investigate the Robertson-Walker cosmology with Lagrangian $R+α_1\hbar R^2+α_2\hbar R^{μν}R_{μν} +L_{rad}$ where $L_{rad}$ means classical source with traceless energy-momentum tensor. We weaken the self-consistence condition (L. Parker, J. Z. Simon, Phys. Rev. {D47}(1993),{1339}). Quantum corrections are expressed as contributions to the effective equation of state. We show that the empty space-time is stable within the class of radiation-filled expanding universes with no order reduction of the field equations.

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Grazyna Siemieniec-Ozieblo, Andrzej Woszczyna. 1999-01-29. Order reduction in semiclassical cosmology. https://doi.org/10.1103/physrevd.59.083504

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