AR-2019-2020

give a stable evolution of the universe. This work has been done in collaboration with N.D. Jerin Mo- han, P.B. Krishna, and Athira Sasidharan. Irom Ablu Meitei Generalized Klein-Gordon equation and quantum gravity corrections to tunnelling of scalar particles from Kerr-Newman black hole In this work, we deduce the generalized Klein- Gordon equation in curved spacetime in the pres- ence of an electromagnetic field from first princi- ples, using the generalized uncertainty principle. Using this equation, we study the tunnelling of scalar particles from a Kerr-Newman black hole. Corrections to the Hawking temperature and en- tropy of the black hole due to quantum gravity ef- fects are discussed. This work has been done in col- laboration with A. Keshwarjit Singh, Talem Ibun- gochouba Singh, and K. Yugindro Singh. Effect of GUP on Hawking radiation of BTZ black hole The Hawking radiation of BTZ black hole is in- vestigated based on generalized uncertainty prin- ciple effect by using Hamilton-Jacobi method and Dirac equation. The tunnelling probability and the Hawking temperature of the spin 1/2 particles of the BTZ black hole is investigated using modi- fied Dirac equation based on the GUP. The modi- fied Hawking temperature for Fermion crossing the black hole horizon includes the mass parameters of the black hole, angular momentum, energy and also outgoing mass of the emitted particle. Be- sides, considering the effect of GUP into account, the modified Hawking radiation of massless par- ticle from a BTZ black hole is investigated using Damour and Ruffini method, tortoise coordinate transformation and modified Klein-Gordon equa- tion. The relation between the modified Hawk- ing temperature obtained by using Damour-Ruffini method and the energy of the emitted particle is derived. The original Hawking temperature is also recovered in the absence of quantum gravity ef- fects. This work has been done in collaboration with Talem Ibungochouba Singh, and Y. Kenedy Meitei Hameeda Mir and Rizwan Ul Haq Ansari Modified theory of gravity and clustering of multi component system of galaxies We analyze the clustering of galaxies using a mod- ified theory of gravity, in which the field content of general relativity has been increased. This increas changes the large distance behaviour of the the- ory, and in weak field approximation, it will also modify the large distance behaviour of Newtonian potential. So, we analyze the clustering of multi- component system of galaxies interacting through this modified Newtonian potential. We obtain the partition function for this multi-component system, and study the thermodynamics of this system, and we analyze the effects of the large distance modi- fication to the Newtonian potential on Helmholtz free energy, internal energy, entropy, pressure and chemical potential of this system, and we obtain also the modified distribution function and the modified clustering parameter for this system, and hence, observe the effect of large distance modifica- tion of Newtonian potential on clustering of galax- ies. This study has been done in collaboration with Behnam Pourhassasn, Mir Faizal, C.P. Masroor, and P. K. Suresh. Sourav Mitra Heavy dark matter particle annihilation in dwarf spheroidal galaxies: Radio signals at the SKA tele- scope A weakly interacting dark matter candidate is diffi- cult to detect at high-energy colliders like the LHC, if its mass is close to, or higher than a TeV. On the other hand, pair-annihilation of such particles may give rise to e + e − pairs in dwarf spheroidal galaxies (dSph), which in turn can lead to radio synchrotron signals that are detectable at the upcoming Square Kilometre Array (SKA) telescope within a moder- ate observation time. We investigate the circum- stances under which this complementarity between collider and radio signals of dark matter can be use- ful in probing physics beyond the standard model of elementary particles. Both particle physics issues and the roles of diffusion and electromagnetic en- ergy loss of the e are taken into account. First, the criteria for detectability of trans-TeV dark matter are analysed independently of the particle physics model(s) involved. We, thereafter, use some bench-