Distruction and creation
Soon after the publication of special relativity astronomers began to look into what would happen when gravity reach such a massive proportions that virtually nothing can escape it’s grasp. the concept of black holes was born, objects so massive that could disrupt the space around them and suck in everything that come close enough yet invisible to any instrument because nothing can escape, not even light. Light being the fastest possible traveler in this universe, as stated in general relativity, would have no chance of escaping the gravity well of a black hole so nothing else would ever leave the black hole. This create a very big problem for astronomer because it seems to violate the conservation of energy in the universe,that means that everything that fall into a black hole leave this universe forever. Potentially, if there will be enough black holes throughout the lifetime of the universe, every bit of information contained in this universe will leave for an unknown place, at the end of time there could be nothing left but the space-time foam at the Plank scale. Even the great Richard Hawkings, possibly the best mind in his field in this century, couldn’t find a way out of this problem.
According to the accepted version of black holes creation, a star bigger than 9 solar masses will exhaust it’s nuclear fuel and while the outer layers of the star will blow up in a majestic explosion, the core of the star will implode on itself and be reduced into a singularity. A singularity is a point in space,no dimensions as we know them will remain, that retain the gravitational field of the entire star. Everything that will get sucked in will join the singularity and add mass to the black hole. One interesting thing about the singularity is that no matter how advanced our instruments can get, the singularity will remain forever out of reach,we will never be able to see it, it seems that nature don’t like “naked” singularities, they always come with event horizons, if you out of the even horizon you simply can’t peak in and see what’s inside and if you are inside you can’t see the rest of the universe, which some gave some astronomer the idea that we may live inside a black hole and don’t know it.
Some scientists speculates that there are 2 types of black hole, fix ones and rotating ones. Some scientists think that a rotating black hole could be a rudimentary time machine because while rotating it drags the space-time around itself and according to some calculations a traveler that goes around the black hole would arrive at the starting point a lot sooner than someone traveling the same distance around a black hole that’s the same size but it’s not rotating and at same speed, thus traveling back in time.
Astronomers have proved that every galaxy has a massive black hole at it’s center and also has proved that there’s a link between the size of the black hole and the speed at which the stars at the edge of the galaxy moves, which suggest that the black hole has an important role in galaxy formation.
Although they are called black hole and everyone think they are invisible that’s not entirely true. The center of the black hole will remain outside the realm of observation probably forever but especially in the case of rotating and active black hole they can be observed indirectly by looking at the accretion disk swirling around them. Because it’s mainly composed by dust and debris spinning at close to the speed of light and unimaginably hot those disks can be seen in the infrared part of the spectrum and when resolution will be good enough we should be able to literally see gas and dust moving around the even horizon in real time.
By destroying everything that falls into them, black holes are certainly the ultimate destroyers, however as the link with galaxy formation clearly show they are at the same time inextricably linked to the creation of everything bigger than a bunch of stars. on top of that black holes activity is closely linked with regions of star formation so they are responsible for the seeding of generation after generation of new stars. Although dark matter seems also fundamental to galaxy formation, the role of black holes cannot be forgotten. Without them the universe would be very different from what it is now and life would have not had the time to develop because all that would be there would be a bunch of stars here and there, too small to even go supernovae. We are here because of their good work.
