Blacks Holes are still a mystery that needs accurate observations. The theory most relevant to explain the concept of Black Hole is the theory of general relativity, that a region or a body that allows light to pass through a Black Hole has to be defined. Another feature which supports the concept of Black Hole is that it does not reflect anything, is invisible and, therefore, can be considered as black.
A Black Hole is a region of space time in which gravity is so intense as to prevent the escape of any form of matter and energy, including light. In its formation is not soltanto determining the mass of the body but also the volume within which it is located? This means that blacks may exist holes of different sizes as small as atoms or as big as whole planetary systems and density is not necessarily huge in comparison with that of Earth.
A Black Hole for example resulting from the collapse of a mass pariah in 10^7 solar masses has a density 100 times lower than that of water. A Black Hole warps space time around it so all the more pronounced the greater is its compact size it determined by the ratio of the radius of the body and its critical radius. If the body falls beyond of the latter, the body collapsing disappears to form a Black Hole. Once the star has fallen to below its critical radius, there will no force able to stop the collapse. We see more in detail the sequence of events leading up to that event.
Imagine you observe a star at the end of its evolution. Its nuclear fuel is close to exhaustion. Just before the start of the gravitational collapse of the structure of the surrounding space is not particularly affected by the presence of photons from the star and its surface are emitted radially in all directions, being particularly flat space-time. The radiation pressures it off altogether. no longer opposed by any force, gravity compresses the outer layers towards the more internal and the initial radius approaches the value of the critical radius, determined by the volume occupied by the star before the collapse.
According to the theories currently considered a Black Hole can be formed only by a star has a mass of at least about 2.5 times that of the Sun, as a result of the Chandrasekhar limit, although because of the various processes of mass loss suffered from the stars at the end of their lives should the original star is at least ten times more massive than the Sun The numbers quoted are indicative only, as they depend on the details of the models used to predict the evolution of stars and, in particular, the chemical composition initial cloud of gas which has given rise to the star in question. It is not ruled out the possibility that a Black Hole might form not stellar, as is supposed, for example for so-called primordial blacks holes.
According to data collected so far, astronomers have concluded that in the middle of 2013, the cloud will pass only 40 billion miles from the horizon of the Black Hole's event: a distance sufficient to capture the cloud and then to swallow it. Gas and dust will take years to fall completely into the Black Hole, so astronomers can watch the event in detail.
Spaghetti space, explains Stefan Gillessen, the Max Planck Institute in Garching, Germany, is among the authors of the discovery: The idea of an astronaut near a Black Hole that is stretched out like a noodle is very popular in science fiction. But now we can see if a real object like this will really be destroyed through the cloud spaghettificazione. The cloud is composed only of dust and gas but has a considerable mass: about three times that of which the Earth. On Focus newsstands around February 20, 2012 article explores these issues.
A white hole is connected to a Black Hole through an Einstein-Rosen bridge, and is supposedly the opposite of a time Black Hole. Dr. Nikodem Poplawski research suggests that blacks can have all the holes of the Einstein-Rosen bridges, each connected to a Universe that is formed simultaneously with the Black Hole. From this we can assume that our Universe was formed by a Black Hole exists in another Universe.
To put simply, imagine a membrane that separates a container into two sections: One without water, and the other full of water. If a hole is practised on this membrane, the water contained in full section would begin to be sucked from one end of the Hole (Black Hole), and to be projected into the empty section from the other end (white hole). If a part is removed from the field, the other is added. The membrane is the space-time separation between our Universe
and the one that has the Black Hole that has created our container. The only difference with the analogy of a container of water is that there is a finite number of Universes already created, but each Black Hole would be a bridge between one world and another, making it virtually unlimited number of Universes exists.