Dark matter in galactic structure: From the milky way to the high redshift universe

Different cosmological models relying upon different dark matter (DM) particle candidates such as WIMPS, sterile neutrinos or axions, can provide a successful enough description of the large scale structure of the Universe. However, important open questions remain to be answered on galaxy scales. They include how to robustly infer and predict the inner/outer slope of the DM profiles; how DM concentrates towards galaxy centers, or which is the nature of the relation between supermassive black holes (SMBHs) and their hosting halos. Another unresolved and seemingly unrelated problem in cosmology has to do with the nature, seed and growth of the SMBHs in the high redshift Universe. Remarkably, by assuming the DM halos are made of neutral fermions held together by gravity, it is possible to obtain key insights to all of the above questions. We present here a brief overview on fermionic DM highlighting on several applications developed in the last decade, as discussed at the 17th Marcel Grossmann Meeting (MG17). Special attention is given to galaxy scales, the Milky Way’s center (nature of SgrA*) and the outer halo shape, as well as the role of the fermionic DM particle on early galaxy formation. The presented results make emphasis on different predictions of the model together with an explicit connection to observational data including astrometric measurements of the S2-orbit, recent EHT images of Sagittarius A* (Sgr A*), GAIA DR3 rotation curve of the Milky Way, and JWST data from the most distant galaxies and little red dots.