One loop stress tensor renormalization in curved background: The Relation between zeta function and point splitting approaches, and an improved point splitting procedure

Aug, 1998
38 pages
Published in:
  • J.Math.Phys. 40 (1999) 3843-3875
e-Print:

Citations per year

1995200320112019202501234
Abstract: (arXiv)
We conclude the rigorous analysis of a previous paper concerning the relation between the (Euclidean) point-splitting approach and the local ζ\zeta-function procedure to renormalize physical quantities at one-loop in (Euclidean) QFT in curved spacetime. The stress tensor is now considered in general DD-dimensional closed manifolds for positive scalar operators Δ+V(x)-\Delta + V(x). Results obtained in previous works (in the case D=4 and V(x)=ξR(x)+m2V(x) =\xi R(x) + m^2) are rigorously proven and generalized. It is also proven that, in static Euclidean manifolds, the method is compatible with Lorentzian-time analytic continuations. It is found that, for D>1D>1, the result of the ζ\zeta function procedure is the same obtained from an improved version of the point-splitting method which uses a particular choice of the term w0(x,y)w_0(x,y) in the Hadamard expansion of the Green function. This point-splitting procedure works for any value of the field mass mm. Furthermore, in the case D=4 and V(x)=ξR(x)+m2V(x) = \xi R(x)+ m^2, the given procedure generalizes the Euclidean version of Wald's improved point-splitting procedure. The found point-splitting method should work generally, also dropping the hypothesis of a closed manifold, and not depending on the ζ\zeta-function procedure. This fact is checked in the Euclidean section of Minkowski spacetime for A=Δ+m2A = -\Delta + m^2 where the method gives rise to the correct stress tensor for m20m^2 \geq 0 automatically.
Note:
  • To appear in J. Math. Phys.
  • field theory: Euclidean
  • space-time
  • regularization: zeta function
  • regularization: point splitting
  • tensor: energy-momentum
  • renormalization
  • any-dimensional
  • expansion: heat kernel
  • field theory: scalar