What are supermassive black holes?

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These giants are real "sinks" that engulf all the matter nearby. Its mass is so huge that it changes the gravitational field around it in a brutal way. In fact, it is common to say, colloquially speaking, that even light is not able to escape the influx of a black hole. But if a black hole looks monstrous, supermassive black holes are even more monstrous. We speak of galactic titans with the mass of millions or tens of billions of suns like ours. It is estimated that the galaxies, at their center, are governed by a supermassive black hole. There is plenty of evidence to think that in the center of the Milky Way lies Sagittarius A, one of these supermassive black holes.

Among other differences, supermassive black holes are so colossal that their size confers them unique properties. For example, their density is much lower than that of their siblings. On the other hand, the horizon of events, the last line that we can observe, is enormous. Great. So much that it encompasses, at times, whole solar systems or more. Finally, the known tidal force, caused in its vicinity, is much smaller because of the size of its radio.

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The origin of supermassive black holes

As there are no stars of mass so large, supermassive black holes can not directly be the fruit of a stellar collapse. In fact, its training mechanism is not yet very clear. It could be a massive star that collapses and gives rise to a black hole that grows slowly feeding on other stars, or a huge cloud of gas that collapses directly under its own gravity.

Whatever the origin of supermassive black holes, their existence is, in any case, totally possible. General relativity clear on this point: if you manage to concentrate a billion solar masses in a region of the size of the solar system, the situation is mathematically similar to that of a black hole of stellar origin, space and time will deform extremely, And even the light can no longer escape.

More details here: Black holes

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