Cosmological perturbation theory and quantum gravity

Romeo Brunetti, Klaus Fredenhagen, Thomas-Paul Hack, Nicola Pinamonti, Katarzyna Anna Rejzner

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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.
Original languageEnglish
Number of pages20
JournalJournal of High Energy Physics
Issue number32
Publication statusPublished - 4 Aug 2016

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© The Author(s) 2016.

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