Speaker
Description
The spacetimes with the NUT parameter are Petrov type D spacetimes commonly associated with a problematic singularity of their axis of symmetry.
One of the possible solutions is to compactify the orbits of the symmetries, which imposes the Hopf fibration structure onto the spacetime. In the simplest case of the Taub-NUT solution this has been done already by Misner, via a so called Misner's interpretation.
We provide a recipe for extension of this method to the general type D spacetimes (including mass, rotation, acceleration, NUT parameter and the cosmological constant) - it is achieved by imposing the U(1)-principle bundle structure onto the space of the orbits of suitably chosen Killing vector fields, from which the non-singular spacetime can be constructed.
I will discuss the relation to the local theory of horizons, as well as possible applications to the cosmology and regularising the curvature singularities of more widely studied black-hole spacetimes.
