1985/12/01 by Masayuki Umemura, Satoru Ikeuchi · 2 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Scientific Research and Discoveries
paper · doi:10.1086/163726
openalex publication_date 1985/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/11
The collisionless relics dominating the presently considered Einstein-de Sitter universe are neutrinos, as hot dark matter, and X-particles having negligible thermal velocity, as cold dark matter (CDM). On scales greater than that of neutrino collisionless damping, neutrino fluctuations develop with time, producing large scale, neutrino-overdense (NOD) and underdense (NUD) regions that subsequently evolve into superclusters and huge voids, respectively. Calculations are presented for the growth of fluctuations of CDM and induced fluctuations of baryons on subgalactic scales in both NOD and NUD regions, from the recombination epoch to the present. It is shown that dwarf galaxies are preferentially formed in NOD regions, and that subgalactic baryon fluctuations in NUD regions are subject to UV heating by QSOs before collapse.