Accretion of New Variable Modified Chaplygin Gas and Generalized Cosmic Chaplygin Gas onto Schwarzschild and Kerr-Newman Black holes

In this work, we have studied accretion of the dark energies NVMCG and GCCG onto the Schwarzschild and Kerr-Newman Black holes. We find the expression of the critical four velocity component which gradually decreases for the fluid flow towards the Schwarzschild as well as Kerr-Newman Black hole. We also find the expression for change of masses of the black hole in both cases. For the Kerr-Newman black hole which is rotating and charged we calculate the specific angular momentum and total angular momentum. We showed that in both cases due to accretion of the dark energy mass of the black hole increases and angular momentum increases in case of Kerr-Newman black hole.Comment: 12 pages, 14 figures, Accepted for publication in European Physical Journal

Dynamical Study of DBI-essence in Loop Quantum Cosmology and Braneworld

We have studied homogeneous isotropic FRW model having dynamical dark energy DBI-essence with scalar field. The existence of cosmological scaling solutions restricts the Lagrangian of the scalar field $\phi$. Choosing $p=X g(X e^{\lambda \phi})$, where $X=-g^{\mu\nu} \partial_\mu \phi \partial_\nu \phi /2$ with $g$ is any function of $X e^{\lambda \phi}$ and defining some suitable transformations, we have constructed the dynamical system in different gravity: (i) Loop Quantum Cosmology (LQC), (ii) DGP BraneWorld and (iii) RS-II Brane World. We have investigated the stability of this dynamical system around the critical point for three gravity models and investigated the scalar field dominated attractor solution in support of accelerated universe. The role of physical parameters have also been shown graphically during accelerating phase of the universe.Comment: 13 pages, 8 figures, Accepted in European Physical Journal