SPEAKER: Filip Hejda (CENTRA)
ABSTRACT: Metrics describing "magnetised Kerr-Newman black holes" can be obtained using a generating technique called Harrison transformation. These solutions are very complicated and they are not asymptotically flat, which limits their applications. In this talk, I will focus on their extremal cases and investigate their properties by constructing simpler spacetimes that exhibit their geometries near degenerate horizons. It is possible to show that the near-horizon geometries of extremal magnetised Kerr-Newman black holes can be characterised by just one dimensionless parameter: "effective Kerr-Newman mixing angle". I will illustrate this fact using special cases and discuss its corollaries like black hole Meissner effect.