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

Journal Article · 11 December 2019 · Physical Review D

DOI: https://doi.org/10.1103/physrevd.100.125010 · OSTI ID:1579291

Arza, Ariel ^[1]; Chakrabarty, Sankha S. ^[1]; Enomoto, Seishi  ^[2]; Han, Yaqi ^[1]; Todarello, Elisa  ^[3]

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1. Univ. of Florida, Gainesville, FL (United States)
2. Sun Yat-Sen Univ., Guangzhou (China); Univ. of Florida, Gainesville, FL (United States); High Energy Accelerator Research Organization (KEK), Tsukuba (Japan)
3. Univ. of Florida, Gainesville, FL (United States); Karlsruhe Inst. of Technology (KIT) (Germany)

Quantum fields with large degeneracy are often approximated as classical fields. Here, we show how the 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 perturbation in only one mode. In quantum field theory, modes satisfying both momentum and energy conservation of the quasiparticles, 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.

• Research Organization: Univ. of Florida, Gainesville, FL (United States)
• Sponsoring Organization: USDOE Office of Science (SC); Heising-Simons Foundation; Chilean Commission on Research, Science and Technology (CONICYT); Japan Society for the Promotion of Science (JSPS); European Unions Horizon 2020; USDOE
• Grant/Contract Number: SC0010296; 2015-109; 78180100; JP18H03708; JP17H01131; 674896
• OSTI ID: 1579291
• Alternate ID(s): OSTI ID: 1802078
• Journal Information: Physical Review D, Vol. 100, Issue 12; ISSN 2470-0010
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English