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2
votes
1answer
85 views

Metric diameter of a ring singularity

In the Kerr metric the ring singularity is located at the coordinate radius $r=0$, which corresponds to a ring with the cartesian radius $R=a$. So the center of the ring singularity in cartesian ...
2
votes
1answer
68 views

Complex-valued event horizon of a Kerr black hole?

The Kerr metric has two physical relevant surfaces on which it appears to be singular. Solving the quadratic equation $1/g_{rr} = 0$ yields the solution: $$r_H^\pm=\frac{G M}{c^2}\pm\sqrt{\left(\frac{...
1
vote
0answers
58 views

Would naked singularities have a complex irreducible mass?

The formula for the irreducible mass, also known as the Christodoulou and Ruffini equation, is $$M_{\rm irr} = \frac{\sqrt{2 M^2-Q^2+2 M \sqrt{M^2-Q^2-a^2}}}{2}$$ where M is the mass equivalent of ...
2
votes
1answer
137 views

Is a Kerr ring singularity a closed string?

I’m obviously not a scientist, but has anyone considered that a Kerr ring singularity might basically be a closed string? The singularity spins in one direction only and is incredibly flat and thin (...
3
votes
1answer
757 views

Ring singularity of Kerr metric

I have been reading about the Kerr metric using various sources (Wald's textbook, Visser's The Kerr spacetime: A brief introduction etc.). I could not understand exactly why the singularity structure ...
2
votes
1answer
308 views

Killing Horizon for Kerr Black Hole

I have some confusion about Killing Horizon of BH. Since a Killing Horizon (KH) is a null hyper-surface at which killing vector $k^{\mu}$ is null; $k^{\mu}k_{\mu}=0.$ For time translation symmetry $...
7
votes
2answers
340 views

What happens to a particle in the exact center of a Kerr black hole?

Kerr black holes (and Kerr-Newman black holes), instead of the "point" singularity theorized in spherically symmetric black holes, instead have a "ring" singularity, spread along the equatorial plane ...