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arXiv · 1603.06206

Conformally-related Einstein-Langevin equations for metric fluctuations in stochastic gravity

Seema Satin·H. T. Cho·Bei Lok Hu
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Abstract

For a conformally-coupled scalar field we obtain the conformally-related Einstein-Langevin equations, using appropriate transformations for all the quantities in the equations between two conformally-related spacetimes. In particular, we analyze the transformations of the influence action, the stress energy tensor, the noise kernel and the dissipation kernel. In due course the fluctuation-dissipation relation is also discussed. The analysis in this paper thereby facilitates a general solution to the Einstein-Langevin equation once the solution of the equation in a simpler, conformally-related spacetime is known. For example, from the Minkowski solution of Martin and Verdaguer, those of the Einstein-Langevin equations in conformally-flat spacetimes, especially for spatially-flat Friedmann-Robertson-Walker models, can be readily obtained.

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Seema Satin, H. T. Cho, Bei Lok Hu. 2016-03-20. Conformally-related Einstein-Langevin equations for metric fluctuations in stochastic gravity. https://doi.org/10.1103/physrevd.94.064019

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