Publication date: Mar 2012
Abstract:
String theory indicates the existence of primordial Kerr superspinars,
extremely compact objects with exterior described by the Kerr
naked-singularity geometry. The primordial superspinars have to be
converted to a black hole due to accretion, but they could survive to
the era of high-redshift quasars. We discuss observational phenomena
caused by the primordial Kerr superspinars in this era, considering the
properties of corotating Keplerian accretion discs orbiting such
superspinars and the optical phenomena modified by their presence. The
potential well around a near-extreme superspinar with spin a very close
to the extreme black hole value a = 1 is very deep so that the
efficiency of the accretion process reaches 157.7%, influencing thus
significantly the spectral continuum of corotating Keplerian discs and
giving a signature of near-extreme superspinars. Such superspinars can
also serve as an efficient accelerator for extremely high-energy
collisions. Phenomena enabling a clear distinction of primordial Kerr
superspinars and black holes are related to the disc oscillations with
the radial and vertical epicyclic frequencies and the most profound
could be differences implied by the profiled spectral lines generated in
the innermost parts of the corotating Keplerian discs.
Authors:
Stuchlík, Zdeněk; Schee, Jan;