Covariant perturbation expansion of off-diagonal heat kernel
arXiv:1603.00446 · doi:10.1007/s10773-016-2968-0
Abstract
Covariant perturbation expansion is an important method in quantum field theory. In this paper an expansion up to arbitrary order for off-diagonal heat kernels in flat space based on the covariant perturbation expansion is given. In literature, only diagonal heat kernels are calculated based on the covariant perturbation expansion.
To appear in International Journal of Theoretical Physics