Future deceleration due to effect of event horizon on backreaction from inhomogeneities
Majumdar, Archan S. (S. N. Bose National Centre for Basic Sciences)

The present acceleration of the universe leads to the formation of a cosmological future event horizon. We explore the effects of the event horizon on cosmological backreaction due to inhomogeneities in the universe. Beginning from the onset of the present accelerated era, we show that backreaction in presence of the event horizon causes acceleration to slow down in the subsequent evolution. Our results indicate that even if the cause for the present acceleration is unrelated to any effect due to cosmological inhomogeneities, backreaction from them in the presence of the event horizon could lead to a transition to deceleration eventually, ensuring avoidance of a big rip.