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arXiv · 1202.6332

Spectral functions of non essentially selfadjoint operators

H. Falomir·P. A. G. Pisani
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Abstract

One of the many problems to which J.S. Dowker devoted his attention is the effect of a conical singularity in the base manifold on the behavior of the quantum fields. In particular, he studied the small-$t$ asymptotic expansion of the heat-kernel trace on a cone and its effects on physical quantities, as the Casimir energy. In this article we review some peculiar results found in the last decade, regarding the appearance of non-standard powers of $t$, and even negative integer powers of $\log{t}$, in this asymptotic expansion for the selfadjoint extensions of some symmetric operators with singular coefficients. Similarly, we show that the $\zeta$-function associated to these selfadjoint extensions presents an unusual analytic structure.

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H. Falomir, P. A. G. Pisani. 2012-02-28. Spectral functions of non essentially selfadjoint operators. https://doi.org/10.1088/1751-8113/45/37/374017

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