The art of the state

Christopher John Fewster

doi:10.1142/S0218271818430071

The art of the state

Christopher John Fewster

Mathematics

Research output: Contribution to journal › Article › peer-review

Abstract

Quantum field theory on curved spacetimes lacks an obvious distinguished vacuum state. We review a recent no-go theorem that establishes the impossibility of finding a preferred state in each globally hyperbolic spacetime, subject to certain natural conditions. The result applies in particular to the free scalar field, but the proof is model-independent and therefore of wider applicability. In addition, we critically examine the recently proposed `SJ states', that are determined by the spacetime geometry alone, but which fail to be Hadamard in general. We describe a modified construction that can yield an infinite family of Hadamard states, and also explain recent results that motivate the Hadamard condition without direct reference to ultra-high energies or ultra-short distance structure.

Original language	English
Number of pages	27
Journal	International Journal of Modern Physics D
Early online date	13 Mar 2018
DOIs	https://doi.org/10.1142/S0218271818430071
Publication status	Published - 20 Apr 2018
Event	IV Amazonian Symposium on Physics - Pará University, Belém, Brazil Duration: 18 Sep 2017 → 22 Sep 2017 http://www.ufpa.br/ppgf/IVASP/

Bibliographical note

© 2018 World Scientific Publishing Co Pte Ltd. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.

Access to Document

10.1142/S0218271818430071

ArtoftheState
© 2018 World Scientific Publishing Co Pte Ltd. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.
Accepted author manuscript, 318 KB

https://arxiv.org/abs/1803.06836Licence: Unspecified

Cite this

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