Non-linear stability of α′-corrected Friedmann equations

We study the non-linear stability of fixed-point solutions to the alpha '-exact equations from O(d, d) invariant cosmology, with and without matter perturbations. Previous non-linear analysis in the literature is revisited, and its compatibility with known linear perturbation results is shown. Some formal aspects of cosmological perturbations in duality invariant cosmology are discussed, and we show the existence of time-reparameterization invariant variables for perturbations.

Automated summary

We investigate the non-linear stability of fixed-point solutions to the alpha'-exact equations in O(d,d) invariant cosmology, considering both with and without matter perturbations. The previous non-linear analysis in literature is reviewed and its compatibility with known linear perturbation results is demonstrated. We also discuss the formal aspects of cosmological perturbations in duality invariant cosmology and establish the existence of time-reparameterization invariant variables for perturbations.