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arXiv · hep-th/9507097

Adiabatic Vacua and Hadamard States for Scalar Quantum Fields on Curved Spacetime

Wolfgang Junker
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Abstract

Quasifree states of a linear Klein-Gordon quantum field on globally hyperbolic spacetime manifolds are considered. Using techniques from the theory of pseudodifferential operators and wavefront sets on manifolds a criterion for a state to be an Hadamard state is developed. It is shown that ground- and KMS-states on certain static spacetimes and adiabatic vacuum states on Robertson-Walker spaces are Hadamard states. Finally, the problem of constructing Hadamard states on arbitrary curved spacetimes is solved in principle.

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Wolfgang Junker. 1995-07-19. Adiabatic Vacua and Hadamard States for Scalar Quantum Fields on Curved Spacetime. https://arxiv.org/abs/hep-th/9507097

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