Anisotropic Problems related to dark sector of the universe

Abstract

This thesis provides a comprehensive review of the ΛCDM model and alternative theories that seek to incorporate anisotropic considerations in cosmology. Through anin-depth analysis, the study examines howdeviations fromperfect isotropy within the ΛCDMmodelinfluencegravitationaldynamicsandtheformationofcosmicstruc tures. Alternative theories such as f(R) gravity, Inflationary Cosmology, and Emer gent Universe Models are explored as extensions or modifications to the ΛCDM model, each offering unique insights into the dynamics of the universe. While f(R) gravity and Inflationary Cosmology can be viewed as further developments of the ΛCDM model, Emergent Universe Models face challenges in aligning with obser vational data and maintaining the successes of General Relativity in local tests. Overall, the thesis presents a valuable exploration of these alternative cosmologi cal theories and their implications for our understanding of the cosmos.