How fast can a Blackhole grow?

[MKruer]

The smallest sustainable black hole need to be around 10^22 kg/m^3, any smaller then that and the decay would faster then the black hole would be able absorb do to background radiation. This also makes the size of the black hole about the about the thickness of a piece of paper.

If such a small object enter the sun, just how long would it take for the black hole to become noticeable and consume the star. probably thousands to tens of thousands of year is my guess, but i am not sure.

Thanks

[John Van Vliet]

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[MKruer]

Yeah, I guess I have to go back to the drawling board for my would be story. I was looking for a micro black hole to to consume the outer envelope of a star, but its was like how do I get something that has enough mass and more importantly the surface area to consume the outer envelope of a star is a timely manner. I was thinking that the micro back hole could be passed though a companion neutron star, but just the shear velocity required would not alolow enough time in the neutron star to collect enough mass

[MKruer]

OK I have a potential solution based upon my sudo physics of space travel. Basically it involves taking a chunk out of a neutron star and moving it to next to the dwarf star. The Question is what would happen to the original neutron star? Considering that a slip of a few mm results in a starquake that can be seen 50,000ly away. The even would probably bring on the destruction of the star.

example?
White Dwarf SuperNova Ia explosion
http://www.youtube.com/watch?v=_zw6Eih7QG0

So if you took a chunk out of a neutron star would it explode like the white dwarf or is the mass sufficient enough to hold the star together? My first guess would be that no the star would not explode, but it would loose up to half its mass because of the shock wave generated by the sudden removal of the matter.

[Splinterfrag]

Methinks that taking out said chunk of neutron star could cause all the neutronium matter to try to fill up the gap via a sorta of flood. This would almost certainly create a huge blast of gamma rays as well.
Or another possibility is that most of the neutronium would fly away from the star due to a loss of gravity.
Those are my two best guesses