# Turnaround in cyclic cosmology.

@article{Baum2007TurnaroundIC, title={Turnaround in cyclic cosmology.}, author={Lauris Baum and Paul H. Frampton}, journal={Physical review letters}, year={2007}, volume={98 7}, pages={ 071301 } }

It is speculated how dark energy in a brane world can help reconcile an infinitely cyclic cosmology with the second law of thermodynamics. A cyclic model is described, in which dark energy with w<-1 equation of state leads to a turnaround at a time, extremely shortly before the would-be big rip, at which both volume and entropy of our Universe decrease by a gigantic factor, while very many independent similarly small contracting universes are spawned. The entropy of our model decreases almost…

## 125 Citations

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