Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Single-Fluid Approach to Modeling Dark Matter and Dark Energy

Cosmological observations over the past decades have provided overwhelming evidence for the ex istence of dark energy, a mysterious and dominant component responsible for the accelerated expan sion of the universe. The nature of dark energy remains one of the most intriguing puzzles in modern cosmol...

Full description

Saved in:
Bibliographic Details
Main Author: Pillay, Vineshree
Other Authors: Dunsby, Peter
Format: Thesis
Language:English
Published: Department of Mathematics and Applied Mathematics 2025
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Cosmological observations over the past decades have provided overwhelming evidence for the ex istence of dark energy, a mysterious and dominant component responsible for the accelerated expan sion of the universe. The nature of dark energy remains one of the most intriguing puzzles in modern cosmology. This dissertation presents a comprehensive investigation into the class of Unified Dark Energy Models (UDE), which offer a novel approach to understanding the nature of dark energy by unifying it with other cosmic components, in our case dark matter. The first part of this work reviews the theoretical background and observational evidence for dark energy, highlighting the challenges posed by the cosmological constant and other early models. Next, we present an in-depth analysis of various Unified Dark Energy Models proposed in the literature. The Generalized Chaplygin gas and the Logotropic model. Furthermore, we explore the impact of Unified Dark Energy Models on the large-scale structure of the universe and its evolution at the perturbed level. Following this review we look at a newly proposed equation of state "The Murnaghan equation of state" which accounts for both pressure and matter in the early universe, and exhibits Chaplygin-like behaviour in the later universe. The findings of this study contribute significantly to our understanding of dark energy and its interactions with other cosmic components.