Advances in Black Hole Physics and Dark Matter Modelling of the Galactic Halo

Andrew Worsley

Abstract One of the most important unresolved issues of modern physics is the presence of cold dark matter (CDM). Such dark matter appears to be essential in explaining the observed galactic rotation curves and the missing Cosmological dark matter. Recent attention has focused on galactic halos as an explanation of the galactic rotation curves, and on the possibility that galactic halos may consist of massive compact halo objects (MACHOs). Indeed results of experiment by the MACHO collaboration group have confirmed the presence of MACHOs in the galactic halo at statistically significant levels. What remains unclear is, what percentage of the galactic halo can be explained by such MACHOs, and what these MACHOs are likely to be composed of. Recent research shows the “most plausible” candidates for such MACHOs are being identified as primordial black holes. Such primordial black holes can also explain quasar brightness, spectral variations, and multiply lensed quasar systems. The presence of these primordial black holes in the galactic halo can be further modelled using advances in black hole gravitational physics. Indeed it has previously been shown that advances in black hole physics can be used to accurately model both CDM associated with the supermassive black hole at the centre of the galaxy, and Cosmological cold dark matter. To establish whether the same mechanism applies to primordial black holes in galactic halos, the original data from the MACHO project are reanalyzed using these advances in black hole physics. It is concluded that the majority of the CDM mass of the galactic halo can be accounted for by MACHOs by using a reanalysis of the data, and by applying advances in black hole gravitational physics. Importantly these advances in black hole physics offer further readily testable gravitational predictions.