A1 Journal article (refereed)
Quantum transport and the phase space structure of the Wightman functions (2020)

Jukkala, Henri; Kainulainen, Kimmo; Koskivaara, Olli (2020). Quantum transport and the phase space structure of the Wightman functions. Journal of High Energy Physics, 2020 (1), 12. DOI: 10.1007/JHEP01(2020)012

JYU authors or editors

Publication details

All authors or editors: Jukkala, Henri; Kainulainen, Kimmo; Koskivaara, Olli

Journal or series: Journal of High Energy Physics

ISSN: 1126-6708

eISSN: 1029-8479

Publication year: 2020

Volume: 2020

Issue number: 1

Article number: 12

Publisher: Springer

Publication country: Germany

Publication language: English

DOI: http://doi.org/10.1007/JHEP01(2020)012

Open Access: Publication published in an open access channel

Publication is parallel published: https://arxiv.org/abs/1910.10979


We study the phase space structure of exact quantum Wightman functions in spatially homogeneous, temporally varying systems. In addition to the usual mass shells, the Wightman functions display additional coherence shells around zero frequency k0 = 0, which carry the information of the local quantum coherence of particle-antiparticle pairs. We find also other structures, which encode non-local correlations in time, and discuss their role and decoherence. We give a simple derivation of the cQPA formalism, a set of quantum transport equations, that can be used to study interacting systems including the local quantum coherence. We compute quantum currents created by a temporal change in a particle’s mass, comparing the exact Wightman function approach, the cQPA and the semiclassical methods. We find that the semiclassical approximation, which is fully encompassed by the cQPA, works surprisingly well even for very sharp temporal features. This is encouraging for the application of semiclassical methods in electroweak baryogenesis with strong phase transitions.

Keywords: quantum field theory; quantum physics; theoretical physics

Free keywords: thermal field theory; CP violation; quantum dissipative systems

Contributing organizations

Related projects

Dark Universe
Kainulainen, Kimmo
Academy of Finland

Ministry reporting: Yes

Reporting Year: 2020

Preliminary JUFO rating: 2

Last updated on 2020-09-07 at 23:12