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arXiv · 0810.2887

2PI simulations in expanding backgrounds: Doing it anyway!

Anders Tranberg
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Abstract

I set out the 2PI formalism for quantum fields in a Friedmann-Robertson-Walker Universe. I show how one can solve self-consistently for the quantum field evolution and the evolution of the cosmological scale factor, using a renormalised semi-classical Friedmann equation. In a 2PI coupling expansion truncated at O(lambda^2), I perform sample calculations demonstrating kinetic and chemical equilibration in this context.

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Anders Tranberg. 2008-10-16. 2PI simulations in expanding backgrounds: Doing it anyway!. https://doi.org/10.1016/j.nuclphysa.2009.01.048

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