What balck holes are.

Within our galaxy alone, there are millions upon millions of stars. Within our universe, there are millions upon millions of galaxies. Humans have known the existance of stars since they have had eyes. Although interpretations may have differed on what they were, they were always thought of as white glowing specks in the sky, but the mystery does not lie within what we can see, but what we can not see. There are billions of …

…are not relevant in a black hole, the link up can go across different regions of space-time, or even different galaxies or universes. If a wormhole did in fact exist, it is thought that its stability would be very limited, as even the slightest perturbation of it would cause it to collapse. If you could find a stable wormhole, traveling through it would be deadly, as radiation from nearby stars would fry you to death.