6 research outputs found
Gravitational hydrodynamics of large scale structure formation
The gravitational hydrodynamics of the primordial plasma with neutrino hot
dark matter is considered as a challenge to the bottom-up cold dark matter
paradigm. Viscosity and turbulence induce a top-down fragmentation scenario
before and at decoupling. The first step is the creation of voids in the
plasma, which expand to 37 Mpc on the average now. The remaining matter clumps
turn into galaxy clusters. Turbulence produced at expanding void boundaries
causes a linear morphology of 3 kpc fragmenting protogalaxies along vortex
lines. At decoupling galaxies and proto-globular star clusters arise; the
latter constitute the galactic dark matter halos and consist themselves of
earth-mass H-He planets. Frozen planets are observed in microlensing and
white-dwarf-heated ones in planetary nebulae. The approach also explains the
Tully-Fisher and Faber-Jackson relations, and cosmic microwave temperature
fluctuations of micro-Kelvins.Comment: 6 pages, no figure
Do non-relativistic neutrinos constitute the dark matter?
The dark matter of the Abell 1689 galaxy cluster is modeled by thermal,
non-relativistic gravitating fermions and its galaxies and X-ray gas by
isothermal distributions. A fit yields a mass of 1.445 eV. A dark matter fraction
occurs for degrees
of freedom, i. e., for 3 families of left plus right handed neutrinos with
masses . Given a temperature of 0.045 K and a de
Broglie length of 0.20 mm, they establish a quantum structure of several
million light years across, the largest known in the Universe. The virial
-particle temperature of keV coincides with the
average one of X-rays. The results are compatible with neutrino genesis,
nucleosynthesis and free streaming. The neutrinos condense on the cluster at
redshift , thereby causing reionization of the intracluster gas
without assistance of heavy stars. The baryons are poor tracers of the dark
matter density.Comment: Extended published version, 6.1 pages, 2 figure
Model for common growth of supermassive black holes, bulges and globular star clusters: ripping off Jeans clusters
It is assumed that a galaxy starts as a dark halo of a few million Jeans
clusters (JCs), each of which consists of nearly a trillion micro brown dwarfs,
MACHOs of Earth mass. JCs in the galaxy center heat up their MACHOs by tidal
forces, which makes them expand, so that coagulation and star formation occurs.
Being continuously fed by matter from bypassing JCs, the central star(s) may
transform into a super massive black hole. It has a fast growth during
the first mega years, and a slow growth at giga years. JCs disrupted
by a close encounter with this black hole can provide matter for the bulge.
Those that survive can be so agitated that they form stars inside them and
become globular star clusters. Thus black holes mostly arise together with
galactic bulges in their own environment and are about as old as the oldest
globular clusters. The age 13.2 Gyr of the star HE 1523-0901 puts forward that
the Galactic halo was sufficiently assembled at that moment. The star formation
rate has a maximum at black hole mass and bulge mass
. In case of merging supermassive black holes the JCs
passing near the galactic center provide ideal assistance to overcome the last
parsec.Comment: 6 pages latex. Matches published versio