The most mysterious objects in the Universe according torightly one can call black holes - regions of space-time whose gravity is so strong that nothing, not even light, can leave them. It is interesting that in the vastness of the infinite Universe there are black holes, the mass of which exceeds the mass of the Sun by five to one hundred times, but there are also those whose mass exceeds a billion solar holes. Astronomers today believe that supermassive black holes lurk at the heart of most galaxies, while noting that the universe is in the so-called "stellar era" - a stage in the evolution of the universe during which stars and galaxies are born continuously. But what lies beyond the stellar era? The researchers believe that eventually all the ingredients for creating black holes will be depleted, and the stars in the night sky will slowly extinguish, thereby turning black holes into the only inhabitants of the universe. But even these space monsters cannot exist forever. Someday they will also die, lighting up, goodbye, which will perish an empty and lifeless space with fireworks.
How do black holes appear?
Black holes begin their existence with death:when the cores of some massive stars run out of fuel, they move on to the next stage of their evolution and explode. During a powerful explosion, the brightness of supernovae (this is what scientists call them) sharply increases, and then slowly fades away. The explosion is also the cause of the ejection into interstellar space of a significant mass of matter from the outer shell of the star, as well as a huge amount of energy.
That part of the matter that was not ejected into the interstellar medium, as a rule, is transformed either into a compact object - neutron star (if the mass of the star before the explosion was more than 8 solar masses), or in black hole - the region of space-time, in which everything is controlled by Her Majesty's gravity (in the event that the mass of the core remaining after the explosion exceeds the solar mass by five times).
As astronomers note, a similar connection betweenthe birth of a black hole and the death of the star that formed it, a fairly common phenomenon in the Universe. Black holes are especially close to other stars in those corners where star formation occurs at a high rate. Recall also that star formation is a large-scale process during which stars begin to massively form from interstellar gas in a galaxy.
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Evolution of black holes
So, after the birth of a black hole as a resultthe death of a massive star, its main occupation is the absorption of any objects that are nearby. In some cases, the absorbed material (gas and stars) surrounds these space monsters, moving faster and faster and accumulating around them. Since friction between dust generates heat, accretion disk the black hole begins to glow, outlining its shadow or event horizon. It was he who was photographed by scientists in 2019, which my colleague Nikolai Khizhnyak told in detail about in his material.
But besides the fact that the event horizon surroundsblack hole, it is also the key to its demise. This is because any material absorbed by a black hole disappears forever, at least this follows from our understanding of gravity. However, this so-called point of no return does not take into account quantum mechanics - yes, yes, physicists are still working on creating a unified theory of quantum gravity and, by the way, have recently achieved quite interesting results.
1974 eminent British theoretical physicist Stephen Hawking proved that from the point of view of quantum mechanics, escape from a black hole is possible, albeit very, very slowly.How long an individual black hole will live depends on its mass. The larger the black hole gets, the longer it takes to evaporate. In this sense, as astronomy.com noted in an interview with astronomy.com, black holes can cheat death by becoming larger.
Researchers compare this process to sandhours, where the sand at the top is the amount of time left at the black hole. Consuming more and more stars and gas, the voracious space monster continues to add grains of sand to the "ticking" hourglass, even as individual particles seep out. But as the universe ages, the material around the black hole will dry out, signaling its inevitable destruction.
In the last tenth of a second of the black hole's life, it will illuminate everything around with the brightest fireworks, like a million thermonuclear bombs exploding in a very tiny region of space.
By the way, the most powerful everRegistered supernovae (ASSASN-15lh) are now considered 22 trillion times more explosive than a black hole in its last moments. What do you think the end of the universe will be? We will wait for the answer here, as well as in the comments to this article.