Rindler approximation to Kerr-Newman black hole
Facultad de Ciencias, Universidad Nacional Autónoma de México Circuito Exterior, Ciudad Universitaria, 04510, México D.F., Mexico
2 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México Circuito Exterior, Ciudad Universitaria, 04510, México D.F., Mexico
* e-mail: email@example.com
Accepted: 15 October 2015
Published online: 19 November 2015
We show that the Rindler approximation to the time-radial part of the Kerr and Kerr-Newman metrics near their external and internal horizons only holds outside and inside , so respectively inside and outside the external and internal ergospheres, regions where, in Boyer-Lindquist coordinates, both and are negative, but preserving the Lorentzian character of the metric, and i.e. outside the region where closed timelike curves exist. At each point, the choice of Rindler coordinates is not trivial, but depends on the polar angle . The approximation, as is known, automatically gives the absolute values of the surface gravities as the corresponding proper accelerations, and therefore the Hawking temperatures at .
© Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg, 2015