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I've been trying to understand the Poisson-Israel model of a charged black hole recently. (The model is also expected to provide insights into rotating black holes as well as charged ones, as I understand it).

http://prola.aps.org/abstract/PRD/v41/i6/p1796_1

(the full text unfortunately requires one to visit a library with access)

I'd like to be able to answer simple questions such as "what is the fate of an observer who falls into such a hole?

Does he get spaghettified? http://en.wikipedia.org/wiki/Spaghettification

Does he get fried by infinite radiation, crushed by infinite pressures, or see the fate of the universe?

Some specificity may be needed to answer these questions, but at the moment I'm leaving the exact details of said black hole rather vague. Ultimately, I'm trying to generally understand the fate of someone falling into an actual rotating black hole like the one in the center of our galaxy, but I'm more than willing to consider simpler cases first.

I'd also like to better understand what the authors mean by "mass inflation".

So far I'm having a hard time even figuring out the metric. Using Schwarzschild coordinates (r,t) I gather that

[tex]g^{rr} = 1 - 2m(r,t) / r + e^2/r^2[/tex]

m(r,t) appears to be the much-talked about "mass function", and it appears to become infinite (?!) near the inner horizon.

Because r is timelike inside the event horizon, this should be the most interesting metric coefficient, but I'm not sure how one goes about finding the other metric coefficients (other than by redoing the calculations).

Other related questions (this is probably already too long) - how does one justify the model of "backscattering" used to determine how some small component of infalling radiation gets "backscattered" into outwards going radiation?