If you have enough gravity, everything gets sucked in--even light itself. At the boundary of a black hole, time stops completely, and most of what we know of physics breaks down at that point. To generate a black hole, you need to compress some amount of mass into a *very* small volume. There's a good article on the possible creation of artificial black holes here:

artificial_black_holes

As the article points out, these black holes are so small that they almost immediately vanish harmlessly. Or as another article says it, "It's quite hard to destroy the Earth."

livescience

When volume shrinks to zero and mass stays constant - that is a basic black hole. Once a mass shrinks below the radius where light can escape,called the Schwartzchild radius, we can't see it any more, and it effectively goes into another dimension. You can't create a black hole in a laboratory, even though people talk about it. The conditions are too extreme!

Hey, everybody: go out and buy yourselves a copy of Lawrence Krauss's book, The Physics of Star Trek. He explains all this very nicely!Cheers,

A singularity is a mathematical concept at which the curvature of the universe and thus the force of gravity and the density become infinite. There is no theoretical minimum size for a black hole, although small ones (even large ones, given enough time) will evaporate due to the laws of quantum mechanics. There is no known way to "create" gravity; gravity can be simulated by centripetal acceleration, but this is not the same as gravity and there is no way to construct this to create a singularity, because of the symmetry of the situation does not have a central point where forces become infinite (instead, they become zero at the central point!). If you could manufacture a gravitational singularity somehow, there is no reason why you could not make its mass anything you wanted,which means that it would not have to be large. It's only infinite at the singularity itself! A black hole with the mass of a human being would, as a general rule, create the gravitational field of... a human being.