Abstract Details
| Name: Tabasum Affiliation: DEPARTMENT OF PHYSICS, UNIVERSITY OF KASHMIR Conference ID: ASI2016_824 Title : Role of Peculiar Velocities of Galaxies in Gravitational Clustering of Cosmological Many Body Problem Authors and Co-Authors : Tabasum Masood & Naseer Iqbal Abstract Type : Poster Abstract Category : General Relativity and Cosmology Abstract : This thesis presents a study of the role of peculiar velocity of galaxy clusters in cosmological many body problem. The cosmological many body problem can be defined in terms of the gravitational clustering of galaxies in an expanding universe. Many galaxies cluster together under the influence of mutual gravitation and tend to form the largest structures in the universe. The approach of gravitational quasi-equilibrium thermodynamic theory in combination with statistical mechanics have been used to describe these clustered structures. The theory describes galaxies as point masses each with same mass. However, the extension of this theory for extended nature of galaxies give also interesting results. Making use of correlation functions as a tool predicts important results which describe the overall status of dynamical parameters like virial mass, virial radius, virial temperature and peculiar velocity of galaxy clusters. The study of correlated relations among various dynamical parameters seems to be essential in describing the details of the problem. The study provides the dominance of clustering for gravitating particles in the interior regions of galaxy clusters. Using gravitational quasi equilibrium thermodynamics, we develop a theory related to the correlation functions that successfully explains the following: 1. The peculiar velocity of galaxy cluster results showing agreement with the results from observations and N-body simulations. 2. The output of cosmological simulations of galaxy clusters obtained by using Enzo hydro dynamical code for the equation of state shows a peculiar behaviour as expected in the inner regions of a cluster. 3. The results of various derived relations like T_{vir}, V_{pec} and R_{vir} have been used to compute the necessary constants involved in the expressions for the study. 4. The unique behaviour of entropy change of a cosmological system signifies the phenomena of gravitational phase transitions where the systems phase changes from mildly to highly clustered phase and from mildly to unclustered phase. According to this phase transition, two specific latent heats associated with phase transitions are evaluated for necessary physical significances. |