Boundary conditions and infrared divergences

Autor: Lissa de Souza Campos, Claudio Dappiaggi, Luca Sinibaldi
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Physics Letters B, Vol 848, Iss , Pp 138348- (2024)
Druh dokumentu: article
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2023.138348
Popis: We review the procedure to construct quasi-free ground states, for real scalar fields whose dynamics is dictated by the Klein-Gordon equation, on standard static Lorentzian manifolds with a time-like boundary. We observe that, depending on the assigned boundary condition of Robin type, this procedure does not always lead to the existence of a suitable bi-distribution ω2∈D′(M×M) due to the presence of infrared divergences. As a concrete example we consider a Bertotti-Robinson spacetime in two different coordinate patches. In one case we show that infrared divergences do not occur only for Dirichlet boundary conditions as one might expect a priori, while, in the other case, we prove that they occur only when Neumann boundary conditions are imposed at the time-like boundary.
Databáze: Directory of Open Access Journals