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arXiv · 2210.04368

Background independence and field redefinitions in quantum gravity

Roberto Casadio·Alexander Kamenshchik·Iberê Kuntz
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Abstract

It is generally believed that a full-fledged theory of quantum gravity should exhibit background independence and diffeomorphism invariance. In its most general form, the latter comprises field redefinitions, which are diffeomorphisms in configuration space. We show that any path-integral approach to quantum gravity leads to a tension between these properties, such that they cannot hold simultaneously.

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Roberto Casadio, Alexander Kamenshchik, Iberê Kuntz. 2022-12-20. Background independence and field redefinitions in quantum gravity. https://doi.org/10.1016/j.aop.2022.169203

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