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arXiv · 0704.2986

States of Low Energy on Robertson-Walker Spacetimes

Heiner Olbermann
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Abstract

We construct a new class of physical states of the free Klein-Gordon field in Robertson-Walker spacetimes. This is done by minimizing the expectation value of smeared stress-energy. We get an explicit expression for the state depending on the smearing function. We call it a state of low energy. States of low energy are an improvement of the concept of adiabatic vacua on Robertson-Walker spacetimes. The latter are approximations of the former. It is shown that states of low energy are Hadamard states.

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Heiner Olbermann. 2007-04-30. States of Low Energy on Robertson-Walker Spacetimes. https://doi.org/10.1088/0264-9381%2F24%2F20%2F007

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