Spherical collapse approach for non-standard dark matter models and enhanced early galaxy formation in <i>JWST</i>

ABSTRACT Using the spherical collapse approach, we investigate the impact of two alternative dark matter models, each characterized by distinct non-zero equations of state – one constant and the other time-dependent – on the non-linear regime. Specifically, we compare these models to standard cold dark matter by analysing their influence on the linear density threshold for non-relativistic component collapse and virial overdensity. Additionally, we explore the number count of collapsed objects, or dark matter haloes, analogous to the number count of galaxy clusters. Finally, in light of recent discoveries by the JWST Labbe, et al. 2023, indicating the potential for more efficient early galaxy formation at higher redshifts, we investigate how alternative dark matter assumptions can enhance structure formation efficiency during the early Universe.