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arXiv · 1002.4449

Gravity from the extension of spatial diffeomorphisms

Szilard Farkas·Emil J. Martinec
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Abstract

The possibility of the extension of spatial diffeomorphisms to a larger family of symmetries in a class of classical field theories is studied. The generator of the additional local symmetry contains a quadratic kinetic term and a potential term which can be a general (not necessarily local) functional of the metric. From the perspective of the foundation of Einstein's gravity our results are positive: The extended constraint algebra is either that of Einstein's gravity, or ultralocal gravity. If our goal is a simple modification of Einstein's gravity that for example makes it perturbatively renormalizable, as has recently been suggested, then our results show that there is no such theory within this class.

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Szilard Farkas, Emil J. Martinec. 2010-02-24. Gravity from the extension of spatial diffeomorphisms. https://doi.org/10.1063/1.3596173

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