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arXiv · hep-th/0103037

Multiple reflection expansion and heat kernel coefficients

M. Bordag·D. Vassilevich·H. Falomir·E. M. Santangelo
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Abstract

We propose the multiple reflection expansion as a tool for the calculation of heat kernel coefficients. As an example, we give the coefficients for a sphere as a finite sum over reflections, obtaining as a byproduct a relation between the coefficients for Dirichlet and Neumann boundary conditions. Further, we calculate the heat kernel coefficients for the most general matching conditions on the surface of a sphere, including those cases corresponding to the presence of delta and delta prime background potentials. In the latter case, the multiple reflection expansion is shown to be non-convergent.

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M. Bordag, D. Vassilevich, H. Falomir, E. M. Santangelo. 2001-03-08. Multiple reflection expansion and heat kernel coefficients. https://doi.org/10.1103/physrevd.64.045017

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