Within a genuinely gauge invariant approach recently developed for the computation of the cosmo- logical backreaction, we study, in a cosmological inflationary context and with respect to various observers, the impact of scalar fluctuations on the space-time dynamics in the long wavelength limit. We stress that such a quantum backreaction effect is evaluated in a truly gauge independent way using a set of effective equations which describe the dynamics of the averaged geometry. In particular we show under what conditions the free falling (geodetic) observers do not experience any scalar-induced back- reaction in the effective Hubble rate and fluid equation of state.
Backreaction during inflation: A Physical gauge invariant formulation.
MAROZZI, GIOVANNI
2011-01-01
Abstract
Within a genuinely gauge invariant approach recently developed for the computation of the cosmo- logical backreaction, we study, in a cosmological inflationary context and with respect to various observers, the impact of scalar fluctuations on the space-time dynamics in the long wavelength limit. We stress that such a quantum backreaction effect is evaluated in a truly gauge independent way using a set of effective equations which describe the dynamics of the averaged geometry. In particular we show under what conditions the free falling (geodetic) observers do not experience any scalar-induced back- reaction in the effective Hubble rate and fluid equation of state.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.