Only a handful of observations truly constrain the nature of dark matter, which is why dozens of different physical models are still viable. Several of the most popular alternatives predict that dark matter halos slowly “thermalize” over time, gradually changing shape and expanding until they form a central region of nearly constant density -- a core. This transformation would not occur if the dark matter particles were completely collision-less, as assumed in the standard model. Therefore, the presence or absence of such a core provides a powerful way to distinguish between the standard
The Universe is not distributed uniformly. Galaxies are arranged in a gigantic cosmic web made of voids, filaments, and galaxy clusters. These filaments act as enormous “cosmic highways” through which matter and galaxies flow toward the densest regions of the Universe. Understanding how these structures influence galaxy evolution is one of the major goals of modern astrophysics. In this work, we analyzed hundreds of thousands of galaxies from the Sloan Digital Sky Survey (SDSS) to study how galaxy density changes around cosmic filaments in the nearby Universe. Our main goal was to determine
Nuclear star clusters are dense and compact stellar systems, with sizes of a few parsecs, found at the centers of many galaxies. Their formation is thought to be closely connected to the assembly history of their host galaxies, and astronomers think that these clusters contain important clues about how galaxies formed and evolved over cosmic time. Recent studies suggest that different formation pathways may operate in late- and early-type galaxies, but the dominant mechanisms and their dependence on galaxy morphology remain unclear. While most observational studies have focused on early-type