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arXiv · hep-th/0207057

Covariant and quasi-covariant quantum dynamics in Robertson-Walker space-times

Detlev Buchholz·Jens Mund·Stephen J. Summers
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Abstract

We propose a canonical description of the dynamics of quantum systems on a class of Robertson-Walker space-times. We show that the worldline of an observer in such space-times determines a unique orbit in the local conformal group SO(4,1) of the space-time and that this orbit determines a unique transport on the space-time. For a quantum system on the space-time modeled by a net of local algebras, the associated dynamics is expressed via a suitable family of ``propagators''. In the best of situations, this dynamics is covariant, but more typically the dynamics will be ``quasi-covariant'' in a sense we make precise. We then show by using our technique of ``transplanting'' states and nets of local algebras from de Sitter space to Robertson-Walker space that there exist quantum systems on Robertson-Walker spaces with quasi-covariant dynamics. The transplanted state is locally passive, in an appropriate sense, with respect to this dynamics.

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Detlev Buchholz, Jens Mund, Stephen J. Summers. 2002-07-06. Covariant and quasi-covariant quantum dynamics in Robertson-Walker space-times. https://doi.org/10.1088/0264-9381%2F19%2F24%2F310

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