I'm having a hard time understanding what the arguments against stable toroidal black holes are saying. For many of these, I can't figure out if they're talking about:
- A non-rotating toroidal event horizon
- A toroidal event horizon, for which it's matter is moving in the tangential direction (of its center ring) such that the gravitational force is balanced by its acceleration
I am unimpressed and uninterested in #1, since this is predicted by basic Newtonian physics, and the matter starts out violently accelerating toward the center of mass.
A number of academic arguments about the viability of toroidal black holes in the book Black Hole Physics, page 164-165. I think that the term "non-stationary" might be referring to my #2 above, but this isn't explicitly established in that page or two. The most detailed mechanistic logic I found was this quote:
Jacobson and Venkataramani (1995) pointed out that a black hole with toroidal surface topology provides a potential mechanism for violating topological censorship. Specifically, a light ray sent from past null infinity to future null infinity and passing through the hole in the torus would not be deformable to a ray which did not come close to the black hole. Thus, topological censorship implies that a toroidal horizon (if it exists) must close up quickly, before a light ray can pass through.
The 1995 Jacobson and Venkataramani paper does seem to make very strong statements along this thread. But nothing I read about the Cosmic censorship theorem itself sounds even remotely convincing. It's more-or-less saying you can't have naked singularities or causality violations. Neither of those are obvious to me from the above quote's argument.
In layman's terms, it sounds like the arguments say that a stable toroidal black hole would allow you to time travel by going through the donut hole. The notation is probably just beyond my grasp. Does the argument really apply to #2 as I've defined it? And, if so, how can I convince myself of the proposition?