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arXiv · 1806.01543

Wave asymptotics at a cosmological time-singularity: classical and quantum scalar fields

Alain Bachelot
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Abstract

We investigate the propagation of the scalar waves in the FLRW universes beginning with a Big Bang and ending with a Big Crunch, a Big Rip, a Big Brake or a Sudden Singularity. We obtain the sharp description of the asymptotics for the solutions of the linear Klein-Gordon equation, and similar results for the semilinear equation with a subcritical exponent. We prove that the number of cosmological particle creation is finite under general assumptions on the initial Big Bang and the final Big Crunch or Big Brake.

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Alain Bachelot. 2018-06-05. Wave asymptotics at a cosmological time-singularity: classical and quantum scalar fields. https://doi.org/10.1007/s00220-019-03356-0

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