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arXiv · 2012.04507

Dynamical diffeomorphisms

Renata Ferrero·Roberto Percacci
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Abstract

We construct a general effective dynamics for diffeomorphisms of spacetime, in a fixed external metric. Though related to familiar models of scalar fields as coordinates, our models have subtly different properties, both at kinematical and dynamical level. The energy-momentum tensor consists of two independently conserved parts. The background solution is the identity diffeomorphism and the energy-momentum tensor of this solution gives rise to an effective cosmological constant.

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Renata Ferrero, Roberto Percacci. 2020-12-08. Dynamical diffeomorphisms. https://doi.org/10.1088/1361-6382/abf627

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