New Insights into Dark Matter Through Advanced Simulations

Recent studies have provided new insights into the properties and behavior of dark matter through advanced simulations, which are crucial for understanding cosmic structures. A significant contribution comes from a study titled, 'Thermodynamic Origin of the Tully-Fisher Relation in Dark Matter Dominated Galaxies', which introduces the concept of self-interacting dark matter with a scale-dependent equation of state. This theoretical-empirical approach has successfully fitted the rotation curves of 100 dark matter-dominated galaxies, particularly dwarf and low-surface-brightness spiral galaxies, addressing the cusp-core problem. The model indicates that the behavior of dark matter is nearly isothermal and virialized, producing key correlations such as K_0 proportional to V_max squared, supporting the emergence of the canonical Tully-Fisher relation as well as the baryonic Tully-Fisher law semi-theoretically and semi-empirically, according to a submission on ArXiv.

Moreover, another study titled, 'Constraining the Nature of Dark Matter from Tidal Radii of Cluster Galaxy Subhalos', explores the spatial distribution of dark matter through gravitational lensing. This research focuses on the tidal radii of cluster galaxy subhalos, providing diagnostics that can distinguish between collisionless cold dark matter and self-interacting dark matter. The analysis of eight lensing clusters has shown that the outer spatial extents of subhalos are statistically consistent with predictions from cold dark matter models, reinforcing the idea that lensing data can significantly inform our understanding of dark matter's nature.

Additionally, an investigation into the singlet-doublet dark matter model highlights the implications of conversion-driven processes on dark matter relic density. The study elaborates on the fermion structure of dark matter and the allowed parameter space for medium to high mass ranges, specifically for Majorana type dark matter. The findings suggest that this framework could satisfy both relic density and direct detection constraints within a broader parameter space, emphasizing the complexities of modeling dark matter interactions and properties.

These studies collectively enhance our understanding of dark matter behavior, addressing longstanding issues such as the cusp-core discrepancy and the nature of dark matter interactions. They underscore the importance of simulations and empirical data in shaping theories that define the fundamental characteristics of dark matter in the universe, ultimately aiding in the comprehension of cosmic structures and evolution. As research continues to evolve, the interplay between theoretical models and observational data remains pivotal in the quest to unravel the mysteries of dark matter.