Having read a number of books on cosmology and particle physics, I found my-self raking through 5 or 6 books or looking on the web as I tried to remember some tangible fact that had interested me. In the end, I decided to gather this info and post it under various headings as blogs on MySpace. With the introduction of LaTeX at Physics Forums, I decided to move a couple of them over here. Some are a year old, some are more recent. MySpace blogs
Black hole Thermodynamics

## Black Hole Thermodynamics

Posted Mar23-09 at 05:06 AM by stevebd1
Updated Mar25-09 at 05:37 AM by stevebd1

The four laws of black hole thermodynamics-

The Zeroth Law

Surface gravity (κ) is constant over a black holes event horizon.

The First Law

'This law deals with the mass (energy) change, dM when a black hole switches from one stationary state to another.' The following (in natural units) applies-

$$dM=\frac{\kappa}{8\pi}\,dA\,+\,\Omega\,dJ\,+\,\Phi\,dQ$$

where the first term is relative...

## Hawking radiation for Kerr black holes

Posted Nov17-08 at 05:29 AM by stevebd1
Updated Mar23-09 at 05:30 AM by stevebd1

Temperature of a black hole (Hawking radiation)-

$$T=\frac{\kappa \hbar}{2\pi k_bc}$$

Killing surface gravity for a static black hole-

$$\kappa=\frac{c^4}{4Gm}$$

Killing surface gravity for a rotating black hole-

$$\kappa=c^2\ \frac{(r_+-r_-)}{2\left(r_+^2+a^2\right)} =\ 2\left(1+\frac{M}{\sqrt{M^2-a^2}\right)^{-1}}\frac{c^4}{4Gm}$$

(while the second equation is good for...