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arXiv · 1307.0482

"Vacuum-like" Hadamard states for quantum fields on curved spacetimes

Marcos Brum·Klaus Fredenhagen
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Abstract

We present a modification of the recently proposed Sorkin-Johnston states for scalar free quantum fields on a class of globally hyperbolic spacetimes possessing compact Cauchy hypersurfaces. The modification relies on a smooth cutoff of the commutator function and leads always to Hadamard states, in contrast to the original Sorkin-Johnston states. The modified Sorkin-Johnston states are, however, due to the smoothing no longer uniquely associated to the spacetime.

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Marcos Brum, Klaus Fredenhagen. 2013-07-01. "Vacuum-like" Hadamard states for quantum fields on curved spacetimes. https://doi.org/10.1088/0264-9381/31/2/025024

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