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arXiv · 2303.09976

Extracting Hadamard Coefficients from Green's Operators

Lennart Ronge
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Abstract

We develop a formula for the diagonal values of the Hadamard coefficients associated to a normally hyperbolic operator on a globally hyperbolic spacetime in terms of the advanced and retarded Green's operators. We develop a local formula as well as formulae for integrals over (parts of) the diagonal. Furthermore, we develop analogues of the Hadamard expansion for powers of the advanced/retarded Green's operators and an analogue of a resolvent.

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Lennart Ronge. 2023-03-17. Extracting Hadamard Coefficients from Green's Operators. https://arxiv.org/abs/2303.09976

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