The Role of Dark Matter in Galactic Formation and Evolution

Abstract: Dark matter plays a crucial role in the formation, structure, and evolution of galaxies, yet its true nature remains one of the most profound mysteries in astrophysics. This paper examines how dark matter governs galactic rotation curves, large-scale structure formation, and the stability of cosmic structures over billions of years. By integrating N-body simulations, gravitational lensing data, and cosmological models, we analyze the impact of dark matter halos on galactic morphology, star formation rates, and intergalactic interactions. We explore competing theoretical models, including cold dark matter (CDM), warm dark matter (WDM), and self-interacting dark matter (SIDM), to determine how different dark matter properties influence galaxy clustering, merger rates, and disk stability. Furthermore, we assess recent observational constraints from gravitational lensing surveys, cosmic microwave background anisotropies, and high-redshift galaxy formation studies to refine our understanding of how dark matter shapes the cosmic web. Key Highlights: Dark matter’s role in galaxy rotation curves and velocity dispersion profiles. Theoretical models (CDM, WDM, SIDM) and their impact on structure formation. Gravitational lensing as a probe for dark matter distribution. Observational signatures in high-redshift galaxies and cosmic voids. Implications for dark matter particle properties and alternative gravity theories. By synthesizing theoretical predictions with observational data, this paper aims to clarify the role of dark matter in galactic evolution, providing new insights into how galaxies form, merge, and interact within the cosmic web. Keywords: Dark matter, galaxy formation, structure formation, gravitational lensing, N-body simulations, cosmic evolution, cold dark matter, warm dark matter, self-interacting dark matter, large-scale structure, astrophysics.