Black hole hair and electromagnetic signatures of merging and collapsing compact objects Seminar

We estimate the electromagnetic power that can be produced as a precursor to
the black hole merger and at the spin-down stage of the Kerr black hole.

(i) A Schwarzschild black hole moving through a constant magnetic field in
vacuum generate bipolar electromagnetic jets and will slow down
electromagnetically.

(ii) We find that the ``no hair'' theorem is not applicable for black holes
formed from collapse of a rotating magnetized neutron stars which can
self-produce particles via vacuum breakdown, forming a highly conducting
plasma magnetosphere with magnetic field lines effectively ``frozen-in'' the
star both before and during collapse. This introduces a topological
constraint which prohibits the open magnetic field from sliding off the
newly-formed event horizon.