Cosmic Acceleration : Impacts on Black Hole Thermodynamics and Accretion. Current Universe is facing Cosmic acceleration : Large Black Holes are no longer stable, accretion no longer strong

      Аннотация: After 1998 from different observational data we are quite convinced to speculate that our universe is going through an accelerating expansion. Different models are there to analyse this fact. It is to be noted that a large part of these models says about a future singularity which will occur in a finite time(coined as Big Rip). In such a surrounding what will be the fate of the compact objects like black holes? On 2004 E. Babichev et al for the first time have shown that if the fluid which is required to explain the accelerated universe(a negative pressure creating one) is assumed to accrete upon a black hole, the mass of the black hole may get reduced with time. On 2010 R. Biswas et al have shown if such fluids start to accrete the accretion disc may get fainter. Even for galactic accretion the speed of accrete in will be dominated by the speed of wind out. Even it was verified that the generalised second law of thermodynamics is not at all been violated by this process. Thermodynamics studies of black holes say that they are more unstable when they are embedded in expanding universe.

Ключевые слова: Thermodynamics, accretion, Black Hole, dark energy, Modified Gravity.