# Two black holes and the event horizon

ExecNight
Photon is a theory,remember?

And is a paradox at the same time..A particle with no mass? Someone explain what that is please...

Coalescence Catastrophe...

BH Coalescence:

The two body problem of general relativity (Einstein and Rosen 1935) is still unsolved. It cannot be treated analytically. The first numerical solution of the head-on collision of two black holes of equal mass was obtained by Smarr (1979), and Matzner et al. (1995) determined the details of the coalescence.

Two black holes of mass M each orbiting each other will coalesce after time:

$$T_c = \frac{5 c^5 r^4}{512 G^3 M^3}$$
(Misner et al. 1973, equation 36.17b).

I presume that this solution was predicted from Classical GR, and is for 'non-rotating' (zero angular momentum) binary Schwarzschild BHs, which do not exist anyway.

If anyone can locate Misner's original 1973 paper, I will post the equasion derivation.

Reference:
http://online.kitp.ucsb.edu/online/numrel00/smarr/
http://arxiv.org/abs/gr-qc/9809034

Last edited: