2005/07/22 by Steen Hannestad, Andreas Ringwald, Huitzu Tu +1 · 22 citations
Physics and Astronomy · #Astrophysics #Cold dark matter #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Dark matter #Dark matter halo #Decoupling (probability) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Hot dark matter #Matter power spectrum #Mixed dark matter #Observable #Physics #Quantum mechanics #Redshift #Scalar field dark matter #Warm dark matter #Weak gravitational lensing #astro-ph #hep-ph
paper · pdf · doi:10.1088/1475-7516/2005/09/014
published in Journal of Cosmology and Astroparticle Physics 2005(09), 014 (Institute of Physics) · 18 pages, 9 figures, uses iopart.cls
arxiv created 2005/07/22 · openalex publication_date 2005/09/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the difference between thermally produced fermionic and bosonic hot dark matter in detail. In the linear regime of structure formation, their distinct free-streaming behaviours can lead to pronounced differences in the matter power spectrum. While not detectable with current cosmological data, such differences will be clearly observable with upcoming large scale weak lensing surveys for particles as light as m HDM ∼0.2 eV. In the nonlinear regime, bosonic hot dark matter is not subject to the same phase space constraints that severely limit the amount of fermionic hot dark matter infall into cold dark matter halos. Consequently, the overdensities in fermionic and bosonic hot dark matter of equal particle mass can differ by more than a factor of five in the central part of a halo. However, this unique manifestation of quantum statistics may prove very difficult to detect unless the mass of the hot dark matter particle and its decoupling temperature fall within a very narrow window, and . In this case, hot dark matter infall may have some observable consequences for the nonlinear power spectrum and hence the weak lensing convergence power spectrum at at the per cent level.