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arXiv · 1407.3907

Noise kernels of stochastic gravity in conformally-flat spacetimes

H. T. Cho·B. L. Hu
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Abstract

The central object in the theory of semiclassical stochastic gravity is the noise kernel which is the symmetric two point correlation function of the stress-energy tensor. Using the corresponding Wightman functions in Minkowski, Einstein and open Einstein spaces, we construct the noise kernels of a conformally coupled scalar field in these spacetimes. From them we show that the noise kernels in conformally-flat spacetimes, including the Friedmann-Robertson-Walker universes, can be obtained in closed analytic forms by using a combination of conformal and coordindate transformations.

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H. T. Cho, B. L. Hu. 2014-07-15. Noise kernels of stochastic gravity in conformally-flat spacetimes. https://doi.org/10.1088/0264-9381/32/5/055006

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