Note on the pragmatic mode-sum regularization method: Translational-splitting in a cosmological background Articles uri icon

publication date

  • May 2021

start page

  • 1

end page

  • 10

issue

  • 10, 105002

volume

  • 103

International Standard Serial Number (ISSN)

  • 2470-0010

Electronic International Standard Serial Number (EISSN)

  • 2470-0029

abstract

  • 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.

subjects

  • Astronomy
  • Mathematics
  • Physics

keywords

  • quantized scalar fields; energy-momentum tensor; adiabatic regularization; quantum-fields; particle horizons; early universe; stress tensor; singularities; phi-2