PT Journal
AU Beltran-Palau, P
   del Rio, A
   Nadal-Gisbert, S
   Navarro-Salas, J
TI Note on the pragmatic mode-sum regularization method: Translational-splitting in a cosmological background
SO Physical Review D
JI Phys. Rev. D
PY 2021
BP 105002
EP 9pp
VL 103
IS 10
DI 10.1103/PhysRevD.103.105002
LA English
AB The point-splitting renormalization method offers a prescription to calculate finite expectation values of quadratic operators constructed from quantum fields in a general curved spacetime. It has been recently shown by Levi and Ori that when the background metric possesses an isometry, like stationary or spherically symmetric black holes, the method can be upgraded into a pragmatic procedure of renormalization that produces efficient numerical calculations. In this paper we show that when the background enjoys three-dimensional spatial symmetries, like homogeneous expanding universes, the above pragmatic regularization technique reduces to the well-established adiabatic regularization method.
ER