We present a simple proof, using the conservation equations, that any quantum stress tensor on Kerr space-time which is isotropic in a frame which rotates rigidly with the angular velocity of the event horizon must be divergent at the velocity of light surface. We comment on our result in the light of the absence of a ‘true Hartle-Hawking’ vacuum for Kerr.

The equation of cosmic string loops in Kerr-de Sitter spacetimes is derived. Having solved the equation numerically, we find that the loops can evolve except for too small ones in the spacetimes.

Using the energy momentum complex given by Møller in 1978 based on the absolute parallelism, the energy distribution in Kerr spacetime is evaluated. The energy with this spacetime is found to be the same as it was earlier evaluated using different definitions mainly based on the metric tensor.

It is well known that 4–dimensional Kerr–NUT–AdS spacetime possesses the hidden symmetry associated with the Killing–Yano tensor. This tensor is ‘universal’ in the sense that there exist coordinates where it does not depend on any of the free parameters of the metric. Recently the general higher dimensional Kerr–NUT–AdS solutions of the Einstein equations were obtained. We demonstrate that all ...

Smooth time dependent supergravity solutions corresponding to analytic continuations of Kerr black holes are constructed and limits with a local de Sitter phase are found. These solutions are non-singular due to a helical twist in space and a fine tuning of the energy flow in the spacetime. For the extremal limit in which the mass and twist parameters are equal the S-brane undergoes de Sitter e...

Dynamics of relativistic outflows along the rotation axis of a Kerr black hole is investigated using a simple model and the evolution of the speed of the flow relative to the ambient medium is studied. We assume that a flow clump is under the influence of the relativistic tidal force of the central source as well as the Lorentz force due to the large-scale electromagnetic field that is assumed ...

Appetite and gut hormone responses to moderate-intensity continuous exercise versus high1 intensity interval exercise, in normoxic and hypoxic conditions 2 3 Daniel P Bailey, Lindsey R Smith, Bryna C Chrismas, Lee Taylor, David J Stensel, Kevin 4 Deighton, Jessica Douglas, Catherine J Kerr. 5 6 Author affiliations 7 Institute for Sport and Physical Activity Research, Department of Sport Science...

We present black hole uniqueness theorems for the C-metric and Ernst solution. The proof follows a similar strategy as that used to prove the uniqueness of the Kerr-Newman solution, however the presence of an acceleration horizon provides some critical differences. We also show how to derive the Bunting/Mazur result (on the positivity of a suitable divergence required in the proof) using new me...