The power of a black hole. Black holes: the story of the discovery of the most mysterious objects in the universe that we will never see. How to see the invisible
A star can turn into a black hole by the end of its life. During this transformation, the star is compressed very strongly, while its mass is conserved. The star turns into a small but very heavy ball. If we assume that our planet Earth becomes a black hole, then its diameter in this state will be only 9 millimeters. But the Earth will not be able to turn into a black hole, because completely different reactions take place in the core of planets, not the same as in stars.
Such a strong compression and compaction of the star comes from the fact that under the influence of thermonuclear reactions in the center of the star, its force of attraction greatly increases and begins to attract the surface of the star to its center. Gradually, the rate at which the star contracts increases and eventually begins to exceed the speed of light. When a star reaches this state, it ceases to glow, because particles of light - quanta - cannot overcome the force of attraction. A star in this state ceases to emit light, it remains "inside" the gravitational radius - the boundary within which all objects are attracted to the surface of the star. Astronomers call this boundary the event horizon. And beyond this boundary, the force of attraction black hole decreases. Since light particles cannot overcome the gravitational boundary of a star, a black hole can only be detected using instruments, for example, if for some unknown reason a spaceship or another body - a comet or an asteroid - starts to change its trajectory, then most likely it came under the influence of the gravitational forces of a black hole . A controlled space object in such a situation must urgently turn on all the engines and leave the zone of dangerous attraction, and if there is not enough power, then it will inevitably be swallowed up by a black hole.
If the Sun could turn into a black hole, then the planets of the solar system would be inside the gravitational radius of the Sun and it would attract and absorb them. Luckily for us, this won't happen. only very large, massive stars can turn into a black hole. The sun is too small for that. In the process of evolution, the Sun will most likely become an extinct black dwarf. Other black holes that already exist in space are not dangerous for our planet and earthly spacecraft - they are too far from us.
In the popular series "The Big Bang Theory", which you can watch, you will not learn the secrets of the creation of the Universe or the causes of black holes in space. The main characters are passionate about science and work in the department of physics at the university. They constantly get into various ridiculous situations that are fun to watch.
Of all the hypothetical objects in the universe predicted by scientific theories, black holes produce the most eerie impression. And, although assumptions about their existence began to be made almost a century and a half before Einstein's publication of the general theory of relativity, convincing evidence of the reality of their existence has been obtained quite recently.
Let's start with how general relativity addresses the question of the nature of gravity. Newton's law of universal gravitation states that between any two massive bodies in the universe there is a force of mutual attraction. Because of this gravitational pull, the Earth revolves around the Sun. General relativity forces us to look at the Sun-Earth system differently. According to this theory, in the presence of such a massive celestial body as the Sun, space-time, as it were, collapses under its weight, and the uniformity of its fabric is disturbed. Imagine an elastic trampoline on which lies a heavy ball (for example, from a bowling alley). The stretched fabric sags under its weight, creating a rarefaction around. In the same way, the Sun pushes the space-time around itself.
According to this picture, the Earth simply rolls around the resulting funnel (except that a small ball rolling around a heavy one on a trampoline will inevitably lose speed and spiral towards a large one). And what we habitually perceive as the force of gravity in our Everyday life, is also nothing but a change in the geometry of space-time, and not a force in the Newtonian sense. To date, a more successful explanation of the nature of gravity than the general theory of relativity gives us has not been invented.
Now imagine what happens if we - within the framework of the proposed picture - increase and increase the mass of a heavy ball, without increasing its physical dimensions? Being absolutely elastic, the funnel will deepen until its upper edges converge somewhere high above the completely heavier ball, and then it simply ceases to exist when viewed from the surface. In the real Universe, having accumulated a sufficient mass and density of matter, the object slams a space-time trap around itself, the fabric of space-time closes, and it loses contact with the rest of the Universe, becoming invisible to it. This is how a black hole is created.
Schwarzschild and his contemporaries believed that such strange cosmic objects do not exist in nature. Einstein himself not only adhered to this point of view, but also mistakenly believed that he managed to substantiate his opinion mathematically.
In the 1930s, a young Indian astrophysicist, Chandrasekhar, proved that a star that has spent its nuclear fuel sheds its shell and turns into a slowly cooling white dwarf only if its mass is less than 1.4 solar masses. Soon, the American Fritz Zwicky guessed that extremely dense bodies of neutron matter arise in supernova explosions; Later, Lev Landau came to the same conclusion. After the work of Chandrasekhar, it was obvious that only stars with a mass greater than 1.4 solar masses could undergo such an evolution. Therefore, a natural question arose - is there an upper mass limit for supernovae that neutron stars leave behind?
In the late 1930s, the future father of the American atomic bomb, Robert Oppenheimer, established that such a limit does indeed exist and does not exceed several solar masses. It was not possible then to give a more precise assessment; it is now known that the masses of neutron stars must be in the range 1.5-3 Ms. But even from the approximate calculations of Oppenheimer and his graduate student George Volkov, it followed that the most massive descendants of supernovae do not become neutron stars, but go into some other state. In 1939, Oppenheimer and Hartland Snyder proved in an idealized model that a massive collapsing star contracts to its gravitational radius. From their formulas, in fact, it follows that the star does not stop there, but the co-authors refrained from such a radical conclusion.
09.07.1911 - 13.04.2008
The final answer was found in the second half of the 20th century by the efforts of a galaxy of brilliant theoretical physicists, including Soviet ones. It turned out that such a collapse always compresses the star “up to the stop”, completely destroying its substance. As a result, a singularity arises, a "superconcentrate" of the gravitational field, closed in an infinitely small volume. For a fixed hole, this is a point, for a rotating hole, it is a ring. The curvature of space-time and, consequently, the force of gravity near the singularity tend to infinity. In late 1967, American physicist John Archibald Wheeler was the first to call such a final stellar collapse a black hole. The new term fell in love with physicists and delighted journalists who spread it around the world (although the French did not like it at first, because the expression trou noir suggested dubious associations).
The most important property of a black hole is that no matter what gets into it, it will not come back. This applies even to light, which is why black holes get their name: a body that absorbs all the light that falls on it and does not emit its own appears completely black. According to general relativity, if an object approaches the center of a black hole at a critical distance - this distance is called the Schwarzschild radius - it can never go back. (German astronomer Karl Schwarzschild, 1873-1916) last years of his life, using the equations of Einstein's general theory of relativity, he calculated the gravitational field around a mass of zero volume.) For the mass of the Sun, the Schwarzschild radius is 3 km, that is, to turn our Sun into a black hole, you need to condense all of its mass to the size of a small town!
Inside the Schwarzschild radius, the theory predicts even stranger phenomena: all the matter in a black hole gathers into an infinitesimal point of infinite density at its very center - mathematicians call such an object a singular perturbation. At infinite density, any finite mass of matter, mathematically speaking, occupies zero spatial volume. Whether this phenomenon actually occurs inside a black hole, we, of course, cannot experimentally verify, since everything that has fallen inside the Schwarzschild radius does not return back.
Thus, not having the opportunity to "view" a black hole in the traditional sense of the word "look", we can nevertheless detect its presence by indirect signs of the influence of its super-powerful and completely unusual gravitational field on the matter around it.
Supermassive black holes
At the center of our Milky Way and other galaxies is an incredibly massive black hole millions of times heavier than the Sun. These supermassive black holes (as they are called) were discovered by observing the nature of the movement of interstellar gas near the centers of galaxies. The gases, judging by the observations, rotate at a close distance from the supermassive object, and simple calculations using the laws of mechanics of Newton show that the object that attracts them, with a meager diameter, has a monstrous mass. Only a black hole can spin the interstellar gas in the center of the galaxy in this way. In fact, astrophysicists have already found dozens of such massive black holes at the centers of our neighboring galaxies, and they strongly suspect that the center of any galaxy is a black hole.
Black holes with stellar mass
According to our current understanding of the evolution of stars, when a star with a mass greater than about 30 solar masses dies in a supernova explosion, its outer shell flies apart, and the inner layers rapidly collapse towards the center and form a black hole in the place of the star that has used up its fuel reserves. It is practically impossible to identify a black hole of this origin isolated in interstellar space, since it is in a rarefied vacuum and does not manifest itself in any way in terms of gravitational interactions. However, if such a hole was part of a binary star system (two hot stars orbiting around their center of mass), the black hole would still have a gravitational effect on its partner star. Astronomers today have more than a dozen candidates for the role of star systems of this kind, although rigorous evidence has not been obtained for any of them.
In a binary system with a black hole in its composition, the matter of a "living" star will inevitably "flow" in the direction of the black hole. And the substance sucked out by the black hole will spin in a spiral when falling into the black hole, disappearing when crossing the Schwarzschild radius. When approaching the fatal boundary, however, the substance sucked into the funnel of the black hole will inevitably condense and heat up due to more frequent collisions between the particles absorbed by the hole, until it is heated up to the radiation energies of waves in the X-ray range of the electromagnetic radiation spectrum. Astronomers can measure the frequency of this kind of X-ray intensity change and calculate, by comparing it with other available data, the approximate mass of an object “pulling” matter onto itself. If the mass of an object exceeds the Chandrasekhar limit (1.4 solar masses), this object cannot be a white dwarf, into which our luminary is destined to degenerate. In most cases of observed observations of such double X-ray stars, a neutron star is a massive object. However, there have already been more than a dozen cases where the only reasonable explanation is the presence of a black hole in a binary star system.
All other types of black holes are much more speculative and based solely on theoretical research - there is no experimental confirmation of their existence at all. First, these are black mini-holes with a mass comparable to the mass of a mountain and compressed to the radius of a proton. The idea of their origin on initial stage The formation of the Universe immediately after the Big Bang was expressed by the English cosmologist Stephen Hawking (see The Hidden Principle of Time Irreversibility). Hawking suggested that explosions of mini-holes could explain the really mysterious phenomenon of chiselled bursts of gamma rays in the universe. Secondly, some theories of elementary particles predict the existence in the Universe - at the micro level - of a real sieve of black holes, which are a kind of foam from the garbage of the universe. The diameter of such micro-holes is supposedly about 10-33 cm - they are billions of times smaller than a proton. At the moment we do not have any hopes for experimental verification even the very fact of the existence of such black hole-particles, not to mention the fact that at least somehow explore their properties.
And what will happen to the observer if he suddenly finds himself on the other side of the gravitational radius, otherwise called the event horizon. Here begins the most amazing property of black holes. Not in vain, speaking of black holes, we have always mentioned time, or rather space-time. According to Einstein's theory of relativity, the faster a body moves, the greater its mass becomes, but the slower time starts to go! At low speeds under normal conditions, this effect is imperceptible, but if the body (spaceship) moves at a speed close to the speed of light, then its mass increases, and time slows down! When the speed of the body is equal to the speed of light, the mass turns to infinity, and time stops! This is evidenced by strict mathematical formulas. Let's go back to the black hole. Imagine a fantastic situation when a starship with astronauts on board approaches the gravitational radius or event horizon. It is clear that the event horizon is so named because we can observe any events (observe something in general) only up to this boundary. That we are not able to observe this border. However, being inside a ship approaching a black hole, the astronauts will feel the same as before, because. according to their watch, the time will go "normally". The spacecraft will calmly cross the event horizon and move on. But since its speed will be close to the speed of light, the spacecraft will reach the center of the black hole, literally, in an instant.
And for an external observer, the spacecraft will simply stop at the event horizon, and will stay there almost forever! Such is the paradox of the colossal gravity of black holes. The question is natural, but will the astronauts who go to infinity according to the clock of an external observer remain alive. No. And the point is not at all in the enormous gravitation, but in the tidal forces, which in such a small and massive body vary greatly at small distances. With the growth of an astronaut 1 m 70 cm, the tidal forces at his head will be much less than at his feet, and he will simply be torn apart already at the event horizon. So we are in in general terms found out what black holes are, but so far we have been talking about black holes of stellar mass. Currently, astronomers have managed to detect supermassive black holes, the mass of which can be a billion suns! Supermassive black holes do not differ in properties from their smaller counterparts. They are only much more massive and, as a rule, are located in the centers of galaxies - the star islands of the Universe. There is also a supermassive black hole at the center of our Galaxy (the Milky Way). The colossal mass of such black holes will make it possible to search for them not only in our Galaxy, but also in the centers of distant galaxies located at a distance of millions and billions of light years from the Earth and the Sun. European and American scientists conducted a global search for supermassive black holes, which, according to modern theoretical calculations, should be located at the center of every galaxy.
Modern technology makes it possible to detect the presence of these collapsars in neighboring galaxies, but very few have been found. This means that either black holes simply hide in dense gas and dust clouds in the central part of galaxies, or they are located in more distant corners of the Universe. So, black holes can be detected by X-rays emitted during the accretion of matter on them, and in order to make a census of such sources, satellites with X-ray telescopes on board were launched into near-Earth space. Searching for sources of X-rays, the Chandra and Rossi space observatories have discovered that the sky is filled with X-ray background radiation, and is millions of times brighter than in visible rays. Much of this background X-ray emission from the sky must come from black holes. Usually in astronomy they talk about three types of black holes. The first is stellar-mass black holes (about 10 solar masses). They form from massive stars when they run out of fusion fuel. The second is supermassive black holes at the centers of galaxies (masses from a million to billions of solar masses). And finally, the primordial black holes formed at the beginning of the life of the Universe, the masses of which are small (of the order of the mass of a large asteroid). Thus, a large range of possible black hole masses remains unfilled. But where are these holes? Filling the space with X-rays, they, nevertheless, do not want to show their true "face". But in order to build a clear theory of the connection between the background X-ray radiation and black holes, it is necessary to know their number. At the moment, space telescopes have been able to detect only a small number of supermassive black holes, the existence of which can be considered proven. Indirect evidence makes it possible to bring the number of observable black holes responsible for background radiation to 15%. We have to assume that the rest of the supermassive black holes are simply hiding behind a thick layer of dust clouds that only allow high-energy X-rays to pass through or are too far away to be detected. modern means observations.
Supermassive black hole (neighbourhood) at the center of the M87 galaxy (X-ray image). A jet is visible from the event horizon. Image from www.college.ru/astronomy
The search for hidden black holes is one of the main tasks of modern X-ray astronomy. The latest breakthroughs in this area, associated with research using the Chandra and Rossi telescopes, however, cover only the low-energy range of X-ray radiation - approximately 2000-20,000 electron volts (for comparison, the energy of optical radiation is about 2 electron volts). volt). Significant amendments to these studies can be made by the European space telescope Integral, which is able to penetrate into the still insufficiently studied region of X-ray radiation with an energy of 20,000-300,000 electron volts. Importance of learning this type x-rays is that although the X-ray background of the sky has a low energy, multiple peaks (points) of radiation with an energy of about 30,000 electron volts appear against this background. Scientists are yet to unravel the mystery of what generates these peaks, and the Integral is the first telescope sensitive enough to find such X-ray sources. According to astronomers, high-energy beams give rise to the so-called Compton-thick objects, that is, supermassive black holes shrouded in a dust shell. It is the Compton objects that are responsible for the X-ray peaks of 30,000 electron volts in the background radiation field.
But continuing their research, the scientists came to the conclusion that Compton objects make up only 10% of the number of black holes that should create high-energy peaks. This is a serious obstacle to the further development of the theory. Does this mean that the missing X-rays are supplied not by Compton-thick, but by ordinary supermassive black holes? Then what about dust screens for low energy X-rays.? The answer seems to lie in the fact that many black holes (Compton objects) have had enough time to absorb all the gas and dust that enveloped them, but before that they had the opportunity to declare themselves with high-energy X-rays. After absorbing all the matter, such black holes were already unable to generate X-rays at the event horizon. It becomes clear why these black holes cannot be detected, and it becomes possible to attribute the missing sources of background radiation to their account, since although the black hole no longer radiates, the radiation previously created by it continues to travel through the Universe. However, it's entirely possible that the missing black holes are more hidden than astronomers suggest, so just because we can't see them doesn't mean they don't exist. It's just that we don't have enough observational power to see them. Meanwhile, NASA scientists plan to extend the search for hidden black holes even further into the universe. It is there that the underwater part of the iceberg is located, they believe. Within a few months, research will be carried out as part of the Swift mission. Penetration into the deep Universe will reveal hiding black holes, find the missing link for the background radiation and shed light on their activity in the early era of the Universe.
Some black holes are thought to be more active than their quiet neighbors. Active black holes absorb the surrounding matter, and if a "gapless" star flying by gets into the flight of gravity, then it will certainly be "eaten" in the most barbaric way (torn to shreds). Absorbed matter, falling into a black hole, is heated to enormous temperatures, and experiences a flash in the gamma, x-ray and ultraviolet ranges. There is also a supermassive black hole at the center of the Milky Way, but it is more difficult to study than holes in neighboring or even distant galaxies. This is due to the dense wall of gas and dust that gets in the way of the center of our galaxy, because the solar system is located almost on the edge of the galactic disk. Therefore, observations of black hole activity are much more effective for those galaxies whose core is clearly visible. When observing one of the distant galaxies, located in the constellation Boötes at a distance of 4 billion light years, astronomers for the first time managed to trace from the beginning and almost to the end the process of absorption of a star by a supermassive black hole. For thousands of years, this gigantic collapser lay quietly at the center of an unnamed elliptical galaxy until one of the stars dared to get close enough to it.
The powerful gravity of the black hole tore the star apart. Clots of matter began to fall into the black hole and, upon reaching the event horizon, flared brightly in the ultraviolet range. These flares were captured by the new NASA Galaxy Evolution Explorer space telescope, which studies the sky in ultraviolet light. The telescope continues to observe the behavior of the distinguished object even today, because the black hole's meal is not over yet, and the remnants of the star continue to fall into the abyss of time and space. Observations of such processes will eventually help to better understand how black holes evolve with their parent galaxies (or, conversely, galaxies evolve with a parent black hole). Earlier observations show that such excesses are not uncommon in the universe. Scientists have calculated that, on average, a star is absorbed by a typical galaxy's supermassive black hole once every 10,000 years, but since there are a large number of galaxies, star absorption can be observed much more often.
a source
« Science fiction can be useful - it stimulates the imagination and relieves fear of the future. but scientific facts can be much more amazing. Science fiction didn't even envision things like black holes.»
Stephen Hawking
In the depths of the universe for man lies countless mysteries and mysteries. One of them is black holes - objects that even the greatest minds of mankind cannot understand. Hundreds of astrophysicists are trying to discover the nature of black holes, but at this stage we have not even proved their existence in practice.
Film directors dedicate their films to them, and among ordinary people Black holes have become such a cult phenomenon that they are identified with the end of the world and imminent death. They are feared and hated, but at the same time they are idolized and bow before the unknown, which these strange fragments of the Universe are fraught with. Agree, to be swallowed up by a black hole is that kind of romance. With their help, it is possible, and they can also become guides for us in.
The yellow press often speculates on the popularity of black holes. Finding headlines in newspapers related to the end of the world on the planet due to another collision with a supermassive black hole is not a problem. Much worse is that the illiterate part of the population takes everything seriously and raises a real panic. To bring some clarity, we will go on a journey to the origins of the discovery of black holes and try to understand what it is and how to relate to it.
invisible stars
It so happened that modern physicists describe the structure of our Universe with the help of the theory of relativity, which Einstein carefully provided to mankind at the beginning of the 20th century. All the more mysterious are black holes, on the event horizon of which all the laws of physics known to us, including Einstein's theory, cease to operate. Isn't it wonderful? In addition, the conjecture about the existence of black holes was expressed long before the birth of Einstein himself.
In 1783 there was a significant increase in scientific activity in England. In those days, science went side by side with religion, they got along well together, and scientists were no longer considered heretics. Moreover, priests were engaged in scientific research. One of these servants of God was the English pastor John Michell, who asked himself not only questions of life, but also quite scientific tasks. Michell was a very titled scientist: initially he was a teacher of mathematics and ancient linguistics in one of the colleges, and after that he was admitted to the Royal Society of London for a number of discoveries.
John Michell dealt with seismology, but in his spare time he liked to think about the eternal and the cosmos. This is how he came up with the idea that somewhere in the depths of the Universe there may exist supermassive bodies with such powerful gravity that in order to overcome the gravitational force of such a body, it is necessary to move at a speed equal to or higher than the speed of light. If we accept such a theory as true, then even light will not be able to develop the second cosmic velocity (the speed necessary to overcome the gravitational attraction of the leaving body), so such a body will remain invisible to the naked eye.
Michell called his new theory "dark stars", and at the same time tried to calculate the mass of such objects. He expressed his thoughts on this matter in an open letter to the Royal Society of London. Unfortunately, in those days, such research was not of particular value to science, so Michell's letter was sent to the archive. Only two hundred years later, in the second half of the 20th century, it was found among thousands of other records carefully stored in the ancient library.
The first scientific evidence for the existence of black holes
After the release of Einstein's General Theory of Relativity, mathematicians and physicists seriously set about solving the equations presented by the German scientist, which were supposed to tell us a lot about the structure of the Universe. The German astronomer, physicist Karl Schwarzschild decided to do the same in 1916.
The scientist, using his calculations, came to the conclusion that the existence of black holes is possible. He was also the first to describe what was later called the romantic phrase "event horizon" - an imaginary boundary of space-time at a black hole, after crossing which there comes a point of no return. Nothing escapes from the event horizon, not even light. It is beyond the event horizon that the so-called “singularity” occurs, where the laws of physics known to us cease to operate.
Continuing to develop his theory and solving equations, Schwarzschild discovered new secrets of black holes for himself and the world. So, he was able to calculate, solely on paper, the distance from the center of a black hole, where its mass is concentrated, to the event horizon. Schwarzschild called this distance the gravitational radius.
Despite the fact that mathematically Schwarzschild's solutions were exceptionally correct and could not be refuted, the scientific community of the early 20th century could not immediately accept such a shocking discovery, and the existence of black holes was written off as a fantasy, which now and then manifested itself in the theory of relativity. For the next decade and a half, the study of space for the presence of black holes was slow, and only a few adherents of the theory of the German physicist were engaged in it.
Stars that give birth to darkness
After Einstein's equations were taken apart, it was time to use the conclusions drawn to understand the structure of the Universe. In particular, in the theory of the evolution of stars. It's no secret that nothing in our world lasts forever. Even the stars have their own cycle of life, albeit longer than a person.
One of the first scientists who became seriously interested in stellar evolution was the young astrophysicist Subramanyan Chandrasekhar, a native of India. In 1930, he published a scientific work that described the alleged internal structure stars and their life cycles.
Already at the beginning of the 20th century, scientists guessed about such a phenomenon as gravitational contraction (gravitational collapse). At a certain point in its life, a star begins to contract at a tremendous rate under the influence of gravitational forces. As a rule, this happens at the moment of the death of a star, however, with a gravitational collapse, there are several ways for the further existence of a red-hot ball.
Chandrasekhar's supervisor, Ralph Fowler, a respected theoretical physicist in his time, suggested that during a gravitational collapse, any star turns into a smaller and hotter one - a white dwarf. But it turned out that the student "broke" the teacher's theory, which was shared by most physicists at the beginning of the last century. According to the work of a young Hindu, the death of a star depends on its initial mass. For example, only those stars whose mass does not exceed 1.44 times the mass of the Sun can become white dwarfs. This number has been called the Chandrasekhar limit. If the mass of the star exceeded this limit, then it dies in a completely different way. Under certain conditions, such a star at the time of death can be reborn into a new, neutron star - another mystery of the modern Universe. The theory of relativity, on the other hand, tells us one more option - the compression of a star to ultra-small values, and here the most interesting begins.
In 1932, an article appeared in one of the scientific journals in which the brilliant physicist from the USSR Lev Landau suggested that during the collapse, a supermassive star is compressed into a point with an infinitesimal radius and infinite mass. Despite the fact that such an event is very difficult to imagine from the point of view of an unprepared person, Landau was not far from the truth. The physicist also suggested that, according to the theory of relativity, gravity at such a point would be so great that it would begin to distort space-time.
Astrophysicists liked Landau's theory, and they continued to develop it. In 1939, in America, thanks to the efforts of two physicists - Robert Oppenheimer and Hartland Sneijder - a theory appeared that describes in detail a supermassive star at the time of collapse. As a result of such an event, a real black hole should have appeared. Despite the persuasiveness of the arguments, scientists continued to deny the possibility of the existence of such bodies, as well as the transformation of stars into them. Even Einstein distanced himself from this idea, believing that the star is not capable of such phenomenal transformations. Other physicists were not stingy in their statements, calling the possibility of such events ridiculous.
However, science always reaches the truth, you just have to wait a little. And so it happened.
The brightest objects in the universe
Our world is a collection of paradoxes. Sometimes things coexist in it, the coexistence of which defies any logic. For example, the term "black hole" would not be associated in a normal person with the expression "incredibly bright", but the discovery of the early 60s of the last century allowed scientists to consider this statement incorrect.
With the help of telescopes, astrophysicists managed to detect hitherto unknown objects in the starry sky, which behaved quite strangely despite the fact that they looked like ordinary stars. Studying these strange luminaries, the American scientist Martin Schmidt drew attention to their spectrography, the data of which showed results different from scanning other stars. Simply put, these stars were not like the others we are used to.
Suddenly it dawned on Schmidt, and he drew attention to the shift of the spectrum in the red range. It turned out that these objects are much further from us than the stars that we are used to seeing in the sky. For example, the object observed by Schmidt was located two and a half billion light-years from our planet, but shone as brightly as a star some hundred light-years away. It turns out that the light from one such object is comparable to the brightness of an entire galaxy. This discovery was a real breakthrough in astrophysics. The scientist called these objects "quasi-stellar" or simply "quasar".
Martin Schmidt continued to study new objects and found out that such a bright glow can be caused by only one reason - accretion. Accretion is the process of absorption of surrounding matter by a supermassive body with the help of gravity. The scientist came to the conclusion that in the center of quasars there is a huge black hole, which with incredible force draws into itself the matter surrounding it in space. In the process of absorption of matter by the hole, the particles are accelerated to enormous speeds and begin to glow. The peculiar luminous dome around a black hole is called an accretion disk. Its visualization was well demonstrated in Christopher Nolan's film "Interstellar", which gave rise to many questions "how can a black hole glow?".
To date, scientists have found thousands of quasars in the starry sky. These strange, incredibly bright objects are called the beacons of the universe. They allow us to imagine the structure of the cosmos a little better and get closer to the moment from which it all began.
Despite the fact that astrophysicists have been obtaining indirect evidence for the existence of supermassive invisible objects in the Universe for many years, the term "black hole" did not exist until 1967. To avoid complicated names, the American physicist John Archibald Wheeler proposed calling such objects "black holes". Why not? To some extent they are black, because we cannot see them. In addition, they attract everything, you can fall into them, just like in a real hole. And to get out of such a place according to modern laws of physics is simply impossible. However, Stephen Hawking claims that when traveling through a black hole, you can get into another Universe, another world, and this is hope.
Fear of infinity
Due to the excessive mystery and romanticization of black holes, these objects have become a real horror story among people. The tabloid press loves to speculate on the illiteracy of the population, giving out amazing stories about how a huge black hole is moving towards our Earth, which in a matter of hours will swallow solar system, or simply radiates waves of toxic gas towards our planet.
Especially popular is the theme of the destruction of the planet with the help of the Large Hadron Collider, which was built in Europe in 2006 on the territory of the European Council for Nuclear Research (CERN). The wave of panic began as someone's stupid joke, but grew like a snowball. Someone started a rumor that a black hole could form in the particle accelerator of the collider, which would swallow our planet entirely. Of course, the indignant people began to demand a ban on experiments at the LHC, afraid of such an outcome. Lawsuits began to come to the European Court demanding to close the collider, and the scientists who created it to be punished to the fullest extent of the law.
In fact, physicists do not deny that when particles collide in the Large Hadron Collider, objects similar in properties to black holes can appear, but their size is at the level of elementary particle sizes, and such “holes” exist for such a short time that we cannot even record their occurrence.
One of the main experts who are trying to dispel the wave of ignorance in front of people is Stephen Hawking - the famous theoretical physicist, who, moreover, is considered a real "guru" regarding black holes. Hawking proved that black holes do not always absorb the light that appears in accretion disks, and some of it is scattered into space. This phenomenon has been called Hawking radiation, or black hole evaporation. Hawking also established a relationship between the size of a black hole and the rate of its "evaporation" - the smaller it is, the less it exists in time. And this means that all opponents of the Large Hadron Collider should not worry: black holes in it will not be able to exist even for a millionth of a second.
Theory not proven in practice
Unfortunately, the technologies of mankind at this stage of development do not allow us to test most of the theories developed by astrophysicists and other scientists. On the one hand, the existence of black holes is quite convincingly proven on paper and deduced using formulas in which everything converged with every variable. On the other hand, in practice, we have not yet managed to see a real black hole with our own eyes.
Despite all the disagreements, physicists suggest that in the center of each of the galaxies there is a supermassive black hole, which collects stars into clusters with its gravity and makes you travel around the Universe in a large and friendly company. In our Milky Way galaxy, according to various estimates, there are from 200 to 400 billion stars. All these stars revolve around something that has a huge mass, around something that we cannot see with a telescope. It is most likely a black hole. Should she be afraid? - No, at least not in the next few billion years, but we can make another interesting film about her.
Both for scientists of the past centuries, and for researchers of our time, the greatest mystery of space is a black hole. What is inside this completely unfamiliar system for physics? What laws apply there? How does time pass in a black hole, and why can't even light quanta escape from it? Now we will try, of course, from the point of view of theory, and not practice, to understand what is inside a black hole, why it, in principle, was formed and exists, how it attracts the objects that surround it.
First, let's describe this object.
So, a certain region of space in the Universe is called a black hole. It is impossible to single it out as a separate star or planet, since it is neither a solid nor a gaseous body. Without a basic understanding of what spacetime is and how these dimensions can change, it is impossible to comprehend what is inside a black hole. The fact is that this area is not only a spatial unit. which distorts both the three dimensions known to us (length, width and height) and the timeline. Scientists are sure that in the region of the horizon (the so-called area surrounding the hole), time takes on a spatial meaning and can move both forward and backward.
Learn the secrets of gravity
If we want to understand what is inside a black hole, we will consider in detail what gravity is. It is this phenomenon that is key in understanding the nature of the so-called "wormholes", from which even light cannot escape. Gravity is the interaction between all bodies that have a material basis. The strength of such gravity depends on the molecular composition of bodies, on the concentration of atoms, and also on their composition. The more particles collapse in a certain area of space, the greater the gravitational force. This is inextricably linked to the Big Bang Theory, when our universe was the size of a pea. It was a state of maximum singularity, and as a result of a flash of light quanta, space began to expand due to the fact that the particles repelled each other. Exactly the opposite is described by scientists as a black hole. What's inside such a thing according to TBZ? Singularity, which is equal to the indicators inherent in our Universe at the time of its birth.
How does matter get into a wormhole?
There is an opinion that a person will never be able to understand what is happening inside a black hole. Since, once there, he will be literally crushed by gravity and gravity. Actually this is not true. Yes, indeed, a black hole is a region of singularity, where everything is compressed to the maximum. But this is not a “space vacuum cleaner” at all, which is capable of drawing all the planets and stars into itself. Any material object that is on the event horizon will observe a strong distortion of space and time (so far, these units stand apart). The Euclidean system of geometry will begin to falter, in other words, they will intersect, the outlines of stereometric figures will cease to be familiar. As for time, it will gradually slow down. The closer you get to the hole, the slower the clock will go relative to Earth time, but you won't notice it. When hitting the "wormhole", the body will fall at zero speed, but at the same time given unit will equal infinity. curvature, which equates the infinite to zero, which finally stops time in the region of the singularity.
Response to emitted light
The only object in space that attracts light is a black hole. What is inside it and in what form it is there is unknown, but they believe that this is pitch darkness, which is impossible to imagine. Light quanta, getting there, do not just disappear. Their mass is multiplied by the mass of the singularity, which makes it even larger and magnifies it. Thus, if you turn on a flashlight inside the wormhole to look around, it will not glow. The emitted quanta will constantly multiply by the mass of the hole, and, roughly speaking, you will only aggravate your situation.
Black holes everywhere
As we have already figured out, the basis of education is gravity, the value of which there is millions of times greater than on Earth. The exact idea of what a black hole is was given to the world by Karl Schwarzschild, who, in fact, discovered the very event horizon and the point of no return, and also established that zero in a singularity state is equal to infinity. In his opinion, a black hole can form anywhere in space. In this case, a certain material object having a spherical shape must reach the gravitational radius. For example, the mass of our planet must fit in the volume of one pea to become a black hole. And the Sun should have a diameter of 5 kilometers with its mass - then its state will become singular.
New world formation horizon
The laws of physics and geometry work perfectly on earth and in outer space, where space is close to vacuum. But they completely lose their significance on the event horizon. That is why, from a mathematical point of view, it is impossible to calculate what is inside a black hole. The pictures that you can come up with if you bend space in accordance with our ideas about the world are certainly far from the truth. It has only been established that time here turns into a spatial unit and, most likely, some more dimensions are added to the existing ones. This makes it possible to believe that completely different worlds are formed inside the black hole (photo, as you know, this will not show, since the light eats itself there). These universes may be composed of antimatter, which is currently unfamiliar to scientists. There are also versions that the sphere of no return is just a portal that leads either to another world or to other points in our Universe.
Birth and death
Much more than the existence of a black hole, is its birth or disappearance. The sphere that distorts space-time, as we have already found out, is formed as a result of collapse. It could be an explosion big star, collision of two or more bodies in space, and so on. But how did matter, which could theoretically be felt, become a realm of time distortion? The puzzle is in progress. But it is followed by a second question - why do such spheres of no return disappear? And if black holes evaporate, then why doesn't that light and all the cosmic matter that they pulled in come out of them? When the matter in the singularity zone begins to expand, gravity gradually decreases. As a result, the black hole simply dissolves, and ordinary vacuum outer space remains in its place. Another mystery follows from this - where did everything that got into it go?
Gravity - our key to a happy future?
Researchers are confident that the energy future of mankind can be formed by a black hole. What is inside this system is still unknown, but it was possible to establish that on the event horizon any matter is transformed into energy, but, of course, partially. For example, a person, finding himself near the point of no return, will give 10 percent of his matter for its processing into energy. This figure is simply colossal, it has become a sensation among astronomers. The fact is that on Earth, when matter is processed into energy by only 0.7 percent.
Black holes are some of the strangest and most fascinating bodies in the universe. They are extremely dense objects. And they have such a strong gravitational attraction that not even light can escape from their monstrous embrace.
Albert Einstein first predicted the existence of black holes in 1916 in his general theory of relativity. The term "black hole" was coined in 1967 by American astronomer John Wheeler. It was first used in 1971.
There are three types of black holes: ordinary black holes, supermassive black holes, and intermediate black holes.
Ordinary black holes. Small but deadly
In 2014, astronomers discovered an object that turned out to be an intermediate-mass black hole. It is located in an arm of a spiral galaxy.
Black hole theory - how they work
Black holes are incredibly massive. But at the same time they occupy a small area of \u200b\u200bspace. There is a direct relationship between mass and gravity. This means that they have an extremely strong gravitational field. Virtually nothing can escape them. In classical physics, even light entering a black hole cannot leave it.
Such a strong attraction creates an observation problem when it comes to black holes. Scientists simply cannot "see" them the way they can see stars and other objects in space. To detect these objects, scientists rely on the radiation that is emitted when dust and gas are swallowed up by a black hole. , lying in the center of the galaxy, may be shrouded in dust and gas around them. This may block the observation of control emissions.
Sometimes, when matter moves towards a black hole, it ricochets out of the event horizon and flies out rather than being sucked in. Bright jets of material are created, moving at almost relativistic speeds. Although the black hole itself remains invisible, these powerful jets can be seen from great distances.
event horizon
Black holes have three "layers" - outer, event horizon and singularity.
The event horizon of a black hole is where light loses its ability to "escape". When a particle crosses the event horizon, it can no longer leave the black hole. At the event horizon, gravity is constant.
The inner region of a black hole, where its mass is contained, is known as a singularity. This is the only point in space-time where the mass of a black hole is concentrated.
According to the concepts of classical mechanics and physics, nothing can. However, when quantum mechanics is added to the equation, things change a bit. In quantum mechanics, for every particle there is an antiparticle. It is a particle with the same mass and opposite electric charge. When they meet, the particle-antiparticle pair can annihilate.
If a particle-antiparticle pair is created outside the reach of the black hole's event horizon, one of the particles may fall into the black hole and the other be ejected. As a result, the mass of the black hole decreases. This process is called Hawking radiation. And the black hole can start to decay, which is rejected by classical mechanics.
Scientists are still working to come up with equations to understand how black holes work.
Shining light from binary black holes
In 2015, astronomers using the Laser Interferometer Gravitational Wave Observatory ( ) detected gravitational waves for the first time. Since then, several other similar incidents have been observed using this tool. The gravitational waves seen by LIGO originated from the merger of small black holes.
The LIGO observations also provide insight into the direction in which the black hole is spinning. When a pair of black holes spiral around each other, they can spin in the same direction. Or the directions of rotation can be completely different.
There are two theories about how binary black holes form. The first suggests that they formed at about the same time, from two stars. They could be born together and die at about the same time. Companion stars would have a similar direction of rotation. Therefore, the black holes they left behind would also rotate in a similar way.
According to the second model, black holes in a star cluster descend to its center and merge. These companions would have random spin orientations compared to each other. LIGO observations of black holes with different spin orientations provide stronger evidence for this formation theory.
Your death will come before you reach the singularity. A 2012 study suggests that will cause the event horizon to act like a wall of fire, instantly burning you to death.
Black holes don't "suck in". The suction is caused by something being pushed into a vacuum, which a massive black hole is definitely not. Instead, the objects just fall into them.
The first object thought to be a black hole is Cygnus X-1. From In 1971, scientists discovered radio emissions emanating from Cygnus X-1. A massive hidden object was discovered and identified as a black hole.
Cygnus X-1 was the subject of a 1974 friendly dispute between Stephen Hawking and theoretical physicist Kip Thorne. The latter claimed that this source was a black hole. In 1990, Hawking admitted defeat.
Miniature black holes could form immediately after. The rapidly expanding space may have compressed some of its regions into tiny, dense black holes. They were less massive than the Sun.
If a star passes too close to a black hole, it may be swallowed up by it. According to astronomers, Milky Way from 10 million to a billion black holes with masses about three times the mass of the Sun.
String theory suggests more types of massive giant black holes than conventional classical mechanics.
Black holes are amazing stuff for science fiction books and movies. The film relied heavily on the advice of theoretical physicist Kip Thorne. This allowed us to bring real science to the Hollywood product. In fact, the special effects work for the blockbuster has led to a better scientific understanding of what distant worlds might look like when located near a rapidly spinning black hole.
If you find an error, please highlight a piece of text and click Ctrl+Enter.
In contact with
