Cosmological hysteresis in cyclic universe from membrane paradigm
  Cosmological hysteresis is a purely thermodynamical phenomenon caused by the gradient in pressure, hence the characteristic equation of state during the expansion and contraction phases of the universe are different, provided that the universe bounces and recollapses. During hysteresis pressure asymmetry is created due to the presence of a single scalar field in the dynamical process. Also such an interesting scenario has vivid implications in cosmology when applied to variants of modified gravity models described within the framework of membrane paradigm. Cyclic universe along with scalar field leads to the increase in the amplitude of the cosmological scale factor at each consecutive cycles of the universe. Detailed analysis shows that the conditions which creates a universe with an ever increasing expansion, depend on the signature of the hysteresis loop integral $\oint pdV$ and on membrane model parameters. 
Sayantan Choudhury, Shreya Banerjee
hep-th astro-ph.CO gr-qc hep-ph