PT Journal
AU Ferreiro, A
   Pla, S
TI Adiabatic regularization and preferred vacuum state for the lambda phi^4 field theory in cosmological spacetimes
SO Physical Review D
JI Phys. Rev. D
PY 2022
BP 065015
EP 12pp
VL 106
IS 6
DI 10.1103/PhysRevD.106.065015
LA English
AB We extend the method of adiabatic regularization by introducing an arbitrary parameter μfor a scalar field with quartic self-coupling in a Friedmann-Lemaitre-Robertson-Walker spacetime at one-loop order. The subtraction terms constructed from this extended version allow us to define a preferred vacuum state at a fixed time ri 1/4 ri0 for this theory. We compute this vacuum state for two commonly used background fields in cosmology, specially in the context of preheating. We also give a possible prescription for an adequate value for mu.
ER