Spacetime Dependence of Local Temperature in Relativistic Quantum Field Theory

Michael Gransee

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Submission date: 24. Jun. 2016
Pages: 23
Bibtex
MSC-Numbers: 81T28, 81T05, 82C10
Keywords and phrases: local KMS condition, local equilibrium, thermal quantum field theory
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Abstract:
The spacetime dependence of the inverse temperature four-vector β for certain states of the quantized Klein-Gordon field on (parts of) Minkowski spacetime is discussed. These states fulfill a recently proposed version of the Kubo-Martin-Schwinger (KMS) boundary value condition, the so-called “local KMS (LKMS) condition”. It turns out that, depending on the mass parameter m ≥ 0, any such state can be extended either (i) to a LKMS state on some forward or backward lightcone, with β depending linearily on spacetime, or (ii) to a thermal equilibrium (KMS) state on all of Minkowski space with constant β. This parallels previously known results for local thermal equilibrium (LTE) states of the quantized Klein-Gordon field. Furthermore, in the case of a massless field our results point to a discrepancy with some classic results in general approaches to (non-quantum) relativistic thermodynamics.