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arXiv · 1907.04941

Duration of Classicality of an inhomogeneous quantum field with repulsive contact self-interactions

Ariel Arza·Sankha S. Chakrabarty·Seishi Enomoto·Yaqi Han·Elisa Todarello
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Abstract

Quantum fields with large degeneracy are often approximated as classical fields. Here, we show how quantum and classical evolution of a highly degenerate quantum field with repulsive contact self-interactions differ from each other. Initially, the field is taken to be homogeneous except for a small plane wave perturbations in only one mode. In quantum field theory, modes satisfying both momentum and energy conservation of the quasi-particles, grow exponentially with time. However, in the classical field approximation, the system is stable. We calculate the time scale after which the classical field description becomes invalid.

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Ariel Arza, Sankha S. Chakrabarty, Seishi Enomoto, Yaqi Han, Elisa Todarello. 2019-07-10. Duration of Classicality of an inhomogeneous quantum field with repulsive contact self-interactions. https://doi.org/10.1103/physrevd.100.125010

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