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arXiv · 0709.1483

Microcausality in Curved Space-Time

Sergei Dubovsky·Alberto Nicolis·Enrico Trincherini·Giovanni Villadoro
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Abstract

It is well known that in Lorentz invariant quantum field theories in flat space the commutator of space-like separated local operators vanishes (microcausality). We provide two different arguments showing that this is a consequence of the causal structure of the classical theory, rather than of Lorentz invariance. In particular, microcausality holds in arbitrary curved space-times, where Lorentz invariance is explicitly broken by the background metric. As illustrated by an explicit calculation on a cylinder this property is rather non trivial at the level of Feynman diagrams.

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Sergei Dubovsky, Alberto Nicolis, Enrico Trincherini, Giovanni Villadoro. 2007-09-10. Microcausality in Curved Space-Time. https://doi.org/10.1103/physrevd.77.084016

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