Destroying a black hole Is there any (known? theoretical?) way to destroy a black-hole?

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*"Destroy" means forcing it to disappear - before it evaporates through Hawking radiation.

*"Disappear" means that it stops being a black-hole: no more event horizon, no more impossibility for light to escape it, etc - it becomes just a "regular" object of mass or loses the mass completely. (i.e. releases its mass to energy or loses its properties in some other way)

*"Before" means any time before it would fizzle away through Hawking radiation. Even if it's achieved a split-second earlier, it's a win.

 A: The standard definition of a black hole in classical GR is that it has an event horizon. By that definition, there is no way to convert the stuff that has fallen into the hole to other stuff that can then be observed from infinity. That would just mean that the spacetime never met the definition of being a black hole spacetime.
If you had something that formed a singularity by gravitational collapse, but the singularity was observable from infinity (at any time, even much later), then that might be somewhat like what you're describing, although it wouldn't be a black hole by the standard definition. However, the statement that that doesn't happen is the cosmic censorship conjecture. (What Aslan Monahov's answer describes sounds like the kinds of scenarios that have been cooked up in attempts to find counterexamples to cosmic censorship.)
A: Kerr–Newman metric predicts that event horizon can disappear after increasing the impulse momentum of black hole. But I am not sure that you can increase the rotating of black hole, it's totally true that you can lower it. Or you can bombard hole with enough amount of charge.
