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arXiv · 0705.0787

On the gravitational coupling of Hadamard states

Hadi Salehi·Parvin Moyassari·Reza Rashidi
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Abstract

We study the constraints imposed by the Hadamard condition on the two-point function of local states of a scalar quantum field conformally coupled to a gravitational background. We propose a method to assign a stress tensor to the state-dependent part of the two point function which arises as a conserved tensor with an anomalous trace. To characterize the local Hadamard states of physical interest we apply a super-selection rule relating this quantum stress tensor to the matter stress tensor of a conformal invariant gravitational model subject to a conformal symmetry breaking term. This implies that the determination of a Hadamard state may be considered as an integral part of its gravitational coupling via the back-reaction effect.

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Hadi Salehi, Parvin Moyassari, Reza Rashidi. 2007-05-06. On the gravitational coupling of Hadamard states. https://arxiv.org/abs/0705.0787

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