Fluctuations of quantum fields via zeta function regularization
Abstract
Explicit expressions for the expectation values and the variances of some observables, which are bilinear quantities in the quantum fields on a Ddimensional manifold, are derived making use of zeta function regularization. It is found that the variance, related to the second functional variation of the effective action, requires a further regularization and that the relative regularized variance turns out to be 2/N, where N is the number of the fields, thus being independent of the dimension D. Some illustrating examples are worked through. The issue of the stress tensor is also briefly addressed.
 Publication:

Physical Review D
 Pub Date:
 April 2002
 DOI:
 10.1103/PhysRevD.65.085031
 arXiv:
 arXiv:hepth/0201152
 Bibcode:
 2002PhRvD..65h5031C
 Keywords:

 11.10.Wx;
 05.30.Jp;
 11.15.Ex;
 Finitetemperature field theory;
 Boson systems;
 Spontaneous breaking of gauge symmetries;
 High Energy Physics  Theory
 EPrint:
 15 pages, latex, typographical mistakes corrected