Sometime in the late 1960s, one of the most famous physicists of the last century, John Wheeler (1911-2008), appeared in a popular science radio program of the BBC. He talked for a long time and colorfully about various cosmic wonders, and at the end he turned to the painful question for him about all kinds of "incorrect observations and mythical objects."
Here, an American scientist eagerly pounced on the hypothesis of the existence of "frozen" (dark, frozen) stars, which was especially not to his liking. Expressing his contempt for these "physical and mathematical fantasies", he called them "black holes." So, with the light hand of Wheeler, the figurative term "black hole" appeared in the media, and then in scientific works.
The bottomless sinkholes of space-time
Today we call a black hole the result of the most amazing natural phenomenon - the fall “inside themselves” of massive celestial bodies. In Latin, collapsus means "fallen", which is why astronomers often call black holes "collapsars". They have such a super-strong "concentrator" of the gravitational field that nothing, including light, can escape from them.
Historically, black holes were preceded by dark stars discovered “at the tip of a feather” by the British astronomer John Michell (1724-1793). Based on Newton's theory of universal gravitation, Michell described such stars, the force of gravity of which kept even the rays of light. Naturally, it would be impossible to notice such a completely black star. Michell outlined his calculations at one of the meetings of the Royal Society of London in 1784 and immediately came under fire. After all, astronomy of that time did not know such phenomena!
So the idea of dark stars, or, as they are called today, "Newtonian" black holes, was buried for a long time in scientific archives. It was remembered only in the era of Albert Einstein (1879-1955) and his theory of universal gravitation. Einstein's theory linked gravity to the curvature of space and immediately attracted the attention of many physicists.
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His colleague at the Berlin Academy of Sciences Karl Schwarzschild (1873-1916) was able to show that sometimes very concentrated gigantic masses can form a kind of bottomless funnel of space-time.
Amazing things would have to happen near the Schwarzschild collapsar: a person's heart would begin to beat less and less, his clock would hopelessly lag behind, and the light around would turn red. The flow of time itself would slow down, up to solidification near the conditional boundary of the black hole, like a river in frost. Well, what will we see in the depths of the collapsar collapse?
Alas, so strange things are happening there that it is simply impossible to describe them popularly. However, although many physicists argue about the internal structure of black holes, theoretically they have already found applications.
Metro between galaxies
More than 30 years ago, the famous astronomer and science fiction writer Carl Sagan decided to write a novel about interstellar travel and, at the same time, not indulge in empty fantasy, but create a "real" extradimensional tunnel on the pages of his book. To discuss the details, he turned to the prominent theoretical physicist Kip Thorne, who enthusiastically set to work.
Thorne and his collaborators have convincingly proved mathematically that the space-time channel can not only be artificially created, but also maintained in a "working" state. The “wormhole” created in this way in space-time would connect not only the distant corners of our Galaxy, but also the metagalactic expanses.
Sagan and Thorne's collaboration led to the science fiction bestseller Contact, which soon became the basis for the highly entertaining film of the same name. There really is a kind of "metro" between galaxies, along which the main character travels. Meanwhile, Wheeler criticized not only black holes, but all kinds of subspace transitions between them. With great sarcasm, he called them "wormholes", "wormholes" and "worm tunnels." It is simply amazing, but these expressions first entered the lexicon of journalists, and then migrated to scientific works.
Science fiction literature often talks about the most exotic ways to transcend space and time. Even a kind of tactic of future "star wars" was born, when the combat fleet of earthlings "dives" into the subspace of a black hole and suddenly emerges right at the bases of hostile aliens, instantly rushing billions of parsecs.
However, judging by astronomical observations, black holes will require titanic efforts to “tame” them, because they are the most dangerous space objects that form the “relief” of the Universe.
Space cannibals
Astronomers often record monstrous bursts of energy coming from distant space. These can be echoes of the dramatic processes of the death of planets and stars in the sinkholes of black holes. Space monsters tear apart the gaseous body of an inadvertently approaching star and completely "swallow" smaller celestial bodies - planets, comets and asteroids.
A black hole attracts the side of a closely flying star facing it much more strongly than the opposite side. This powerful tidal force stretches the star and causes gas to fall from the star into the black hole. Astronomers have concluded that black holes are not born huge, but that they gradually grow due to the gas and stars of galaxies.
Among the black holes, there are also large fidgets, rapidly moving inside the stellar islands of galaxies. Together with their sedentary brethren, these "space cannibals" constantly not only devour planetary systems like our own solar, but also swallow dust and gas clouds stretching between star clusters.
Astronomers have long noticed that in smaller galaxies, black holes are less massive, with masses of just over a few million solar masses. Black holes at the centers of giant galaxies include billions of solar masses - the fact is that the final mass of a black hole is formed during the formation of a galaxy. In some cases, black holes enlarge not only by absorbing gas from an individual galaxy, but also by merging galaxies, resulting in their black holes merging.
In the very center of the Milky Way is the core of our Galaxy, in which the mysterious object Sagittarius A * is hidden. Astronomers believe that this is the main contender for the role of a black hole with a mass of about four million solar masses.
Periodically, this local "cannibal" of ours devours this or that star. And then special X-ray telescopes register the "death scream" of the luminary in the form of an X-ray pulse. It is with its help that our internal organs are studied in the X-ray room.
However, black holes can be quite peaceful, forming double star systems with ordinary stars. However, this idyll also ends tragically, and after hundreds of millions, and maybe billions of years, the distance between the black hole and the star will be reduced to a critical limit. The movement of the star will become unstable and after a few revolutions around the black monster, it will disappear into its womb.
Mystery of the Tunguska meteorite
In principle, an artificial black hole can also be created. To do this, it is necessary to compress any mass to the size of the gravitational radius (the radius of the sphere on which the gravitational force created by the mass inside this sphere tends to infinity.), And then it itself will begin to catastrophically contract - collapse.
True, this is very difficult to do, because the less the mass, the smaller the gravitational radius. For example, the gravitational radius of the Earth is about one centimeter, and in order to turn the Moon into a black hole, it would have to be compressed to the size of a large molecule.
Nevertheless, with the help of models of microscopic holes, or, as they are more often called, microcollapsars, sometimes they try to explain all sorts of mysterious phenomena. So, there is a hypothesis that the famous Tunguska meteorite was nothing more than a miniature black hole wandering through the vastness of the Universe.
One could, of course, simply dismiss such inventions, but here curious details arise: the complete absence of meteorite remnants, the unusual nature of the explosion, and contradictory observations of the flight path.
There are ideas that such a microcollap-sar had a completely terrestrial origin. The fact is that it was during the fall of the Tunguska meteorite that the great American inventor Nikola Tesla (1856-1943) tested a certain wave resonator on the amazing Wondercliffe tower, which, with the help of "standing waves of the world electrical ether", was supposed to transmit energy throughout the planet.
Urban legends tell how a colossal plasmoid flashed over Podkamennaya Tunguska, instantly collapsing into a black mini-hole. This process caused a hurricane of energy, recorded as a Tunguska miracle.
There is also a version of this hypothesis, in which the Tunguska meteorite itself was precisely a miniature black hole that penetrated our planet with great speed.
How plausible are the conclusions of theoretical physicists? Are there really worm tunnels in space-time, or is this just a kind of "physical and mathematical fantasy"? And the most important question: is it possible to propose any real experiments to create artificial subspace wormholes leading to the space of other dimensions?
Is the LHC a doomsday machine or a microcollapsar generator?
Calculations show that microscopic black holes may well arise in experiments at particle accelerators, such as the well-known Large Hadron Collider (LHC) launched at CERN.
The principle of the LHC is theoretically quite simple: imagine a tube in which two giant cannons shoot towards each other with special projectiles - the elementary particles that make up atoms. When these microscopic projectiles meet, they scatter like fireworks of all sorts of fragments, among which there may be microscopic black holes.
If the LHC physicists discover these micro-objects, then the scientific sensation will far surpass the recent discovery of the "god particle" - the Higgs boson.
Some scientists believe that micro-collapsars are very dangerous objects that can lead to planetary disaster. The launch of the LHC was accompanied by protests, and a group of physicists even sued CERN as an organization that endangers humanity to mortal danger.
In the end, the passions subsided somewhat, since physicists have clearly shown that every moment avalanches of cosmic particles fall on the earth's surface, much exceeding in energy the products of collisions in the LHC. Nevertheless, streams of ultra-high energy cosmic rays pose no danger and do not generate microscopic black holes.
On the other hand, computer models show that if the Earth were visited by a mini-hole, it would immediately fall to the center of our planet and begin to revolve around it, absorbing magma. But no matter how ominous this process may seem, it will take several billion years for it to somehow manifest itself on the surface. So, it is quite possible that we have been living with a black hole under our feet for a long time …
The future of the universe and life in a black hole
It is not known whether humanity will exist in billions of years, but in the optimal version, astronomers of the distant future will be able to observe a completely different Metagalaxy - the visible Universe. Most of the stars will burn out, and the sun-like luminaries will turn into superdense dwarfs. At the same time, more massive stars will become black holes that are even smaller and have such a strong gravitational field that even light cannot overcome it.
However, these remnants will continue to revolve around the galactic center with a period of about 100 million years. Collisions between the remnants will throw some of them out of the galaxy. The rest will settle down in orbits closer to the center and will eventually come together, forming a giant black hole in the center of the Galaxy, which will one day swallow all matter.
What will it be - the end of life and reason in our Universe?
Let's not rush, because some modern theories predict that even in the terrible depths of black holes, whole planets can exist, revolving indefinitely around a central point. According to preliminary calculations, such planets can even be brightly illuminated due to photons trapped from the outside into the trap of the hole and rotating together with other bodies in the same stable orbit.
Only the last question remains to be solved: can life exist on the planets of a black hole? According to some theorists, this is possible. Moreover, fleeing cosmic cataclysms, our future highly developed civilization can find a real refuge in the depths of a supermassive black hole that occupies the core of the Milky Way.
Of course, the colonizers of black holes will have to solve a number of grandiose tasks, such as countering colossal tidal forces and protection from the strongest flux of radiation. However, from the point of view of the evolution of the mind, a civilization that has managed to penetrate into the black hole will possess truly fabulous technologies that can solve the most fantastic problems.
Perhaps, within a few millennia, human civilization will be completely free to open portals to other worlds. In this case, a variety of options may arise: wormholes between distant parts of our Galaxy, subspace tunnels between galaxies at the very edge of the Universe, bridges between the past and the future, wormholes to other worlds.
Then the humanity of the future is not afraid of any cosmic catastrophes, and it will be able to freely travel across different universes, choosing a favorable habitat. Moreover, having figured out how universes are born and why they have different properties, supercivilization can start looking for ready-made ones through the throats of black holes and creating new worlds, more adapted for life and not subject to all sorts of cataclysms.
So, what do black holes hide in themselves? A path to other worlds, boundless energy of the future, the last breath of the Universe or civilization of other worlds?
It is possible that the current generation of students and schoolchildren will know the answers to some of these questions. We can only wait for that exciting moment when astronomers will finally be able to start directly studying "candidates for gravitational collapsars."
Oleg FAYG