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Coarse-grained field wave function in stochastic inflation

Mauricio Bellini
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Abstract

The wave function for the matter field fluctuations in the infrared sector is studied within the framework of inflationary cosmology. These fluctuations are described by a coarse-grained field which takes into account only the modes with wavelength much bigger than the size of the Hubble horizon. The case of a power-law expanding universe is considered and it is found that the relevant phase-space remains coherent under certain circumstances. In this case the classical stochastic treatment for matter field fluctuations is not valid, however, for $p > 4.6$, the system loses its coherence and a classical stochastic approximation is allowed.

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Mauricio Bellini. 2001-04-10. Coarse-grained field wave function in stochastic inflation. https://doi.org/10.1016/s0550-3213(01)00196-1

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