Black holes in Klein space

A bstract The analytic continuation of the general signature (1, 3) Lorentzian Kerr-Taub-NUT black holes to (2, 2) Kleinian is studied. Their global structure characterized by a toric Penrose diagram resembling their counterparts. are found be self-dual when mass and NUT charge equal for any value Kerr rotation parameter . Remarkably, it shown that can eliminated large diffeomorphism; this result also holds in Euclidean signature. from naturally induced S-matrix. Indeed, we show geometry linearized holes, including Kerr-Taub-NUT, captured three-point scattering amplitudes graviton massive spinning particle. This stands sharp contrast counterparts which latter vanishes kinematically enables direct link