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arXiv · 0710.4393

Quantum reference frames and deformed symmetries

Florian Girelli·David Poulin
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Abstract

In the context of constrained quantum mechanics, reference systems are used to construct relational observables that are invariant under the action of the symmetry group. Upon measurement of a relational observable, the reference system undergoes an unavoidable measurement "back-action" that modifies its properties. In a quantum-gravitational setting, it has been argued that such a back-action may produce effects that are described at an effective level as a form of deformed (or doubly) special relativity. We examine this possibility using a simple constrained system that has been extensively studied in the context of quantum information. While our conclusions support the idea of a symmetry deformation, they also reveal a host of other effects that may be relevant to the context of quantum gravity, and could potentially conceal the symmetry deformation.

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Florian Girelli, David Poulin. 2007-10-24. Quantum reference frames and deformed symmetries. https://doi.org/10.1103/physrevd.77.104012

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