Bose–Einstein condensation as an alternative to inflation
It was recently shown that gravitons with a very small mass should have formed a Bose–Einstein condensate (BEC) in the very early universe, whose density and quantum potential can account for the dark matter (DM) and dark energy (DE) in the universe respectively. Here, we show that the condensation can also naturally explain the observed large scale homogeneity and isotropy of the universe. Furthermore, gravitons continue to fall into their ground state within the condensate at every epoch, accounting for the observed flatness of space at cosmological distance scales. Finally, we argue that the density perturbations due to quantum fluctuations within the condensate give rise to a scale invariant spectrum. This therefore provides a viable alternative to inflation, which is not associated with the well-known problems associated with the latter.