2005/09/29 by Philippe Brax, Ph. Brax, Carsten van de Bruck +3
Physics and Astronomy · #Astrophysics #Classical mechanics #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Dark fluid #Dark matter #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Physics #Scalar field #Scalar field dark matter #Structure formation #astro-ph #hep-ph #hep-th
paper · pdf · doi:10.1016/j.physletb.2005.12.055
published as Phys.Lett.B633:441-446,2006 · 13 pages, 4 figures
arxiv created 2005/09/29 · openalex publication_date 2006/01/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Chameleon fields are scalar fields whose mass depends on the ambient matter density. We investigate the effects of these fields on the growth of density perturbations on sub-galactic scales and the formation of the first dark matter halos. Density perturbations on comoving scales R<1pc go non-linear and collapse to form structure much earlier than in standard ΛCDM cosmology. The resulting mini-halos are hence more dense and resilient to disruption. We therefore expect (provided that the density perturbations on these scales have not been erased by damping processes) that the dark matter distribution on small scales would be more clumpy in chameleon cosmology than in the ΛCDM model.