: : : : : If black hole can be a tool for space traveling, why can't we to find some way to use it.

: : You would have to find one first. The nearest black hole large enough that tidal effects are minimal is thought to be at the center of our galaxy - a distance of about 25,000 light years. : : So it will be quite some time before we start using that particular black hole! :)

: :Can we make a black hole on the Earth? :maybe we can't do it now, but we can do it in :the future.

It is possible to produce a man made blackhole in theory!... I read this in A Brief History of Time, in the chapter on blackholes.... "Low-mass black holes could form only if matter was compressed to enourmous densities, by very large external pressures. Such conditions could occur in a very big hydrogen bomb: the physicist John Wheeler once calculated that if one took all the heavy water in all the oceans of the world, they could compress matter at the center so much that a black hole could be created." So there it is.