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arXiv · 1605.02573

Cosmological perturbation theory and quantum gravity

Romeo Brunetti·Klaus Fredenhagen·Thomas-Paul Hack·Nicola Pinamonti·Katarzyna Rejzner
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Abstract

It is shown how cosmological perturbation theory arises from a fully quantized perturbative theory of quantum gravity. Central for the derivation is a non-perturbative concept of gauge-invariant local observables by means of which perturbative invariant expressions of arbitrary order are generated. In particular, in the linearised theory, first order gauge-invariant observables familiar from cosmological perturbation theory are recovered. Explicit expressions of second order quantities are presented as well.

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Romeo Brunetti, Klaus Fredenhagen, Thomas-Paul Hack, Nicola Pinamonti, Katarzyna Rejzner. 2016-05-09. Cosmological perturbation theory and quantum gravity. https://doi.org/10.1007/jhep08(2016)032

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