Black hole in space: where does it come from. Black holes - an explanation for children

All-Russian competition youth research work them. V. I. Vernadsky 2013-14

1.Introduction
My name is Sasha Voynov. I am 8 years old. I'm in second grade. I really like watching the stars. I love studying everything related to space. There are many mysterious and insufficiently studied objects in the Universe. One of the most interesting objects is black holes. Many people believe that black holes do not exist. I will try to prove that they exist.
The topic of black holes is one of the most current topics modern astronomy, astrophysics and cosmology, since these objects help to better understand the structure of our universe, from the moment of the big bang to the present day, and will also make it possible to understand what will happen to our universe in the future.
Purpose of the study: to formulate the concept of “black hole of space”.

Tasks:
1. Study the history of the issue of black holes.
2. Systematize and study information about black holes (occurrence, properties).
3. Conduct experiments.
Research methods: work with literary sources and Internet resources, experiment.
Novelty of the research: the term “Black hole” appeared a long time ago, but a complete study of black holes has not yet been carried out. I came up with experiments with the goal of explaining some of the properties of black holes.
Literature review:
Source of information What I learned
Hawking S. Three books about space and time. The history of the idea of “Black Holes”; how black holes appear, the concept of star collapse; what does space distortion mean? where do black holes live
KIP S. Thorne. Black holes and folds of time: Einstein's daring legacy. How space and time distortion occurs; Einstein's contribution to the development of the theory of the existence of black holes
Ian Nicholson. Universe. Series “Life of the Planet” What does supermassive stars mean, comparison of the sizes of the sun, stars with the size of a car
I explore the world: Det. encycl.: Physics General information about the black hole: the story of how they appear
I explore the world: Det. encycl.: Space The history of the term “Black hole”
Encyclopedic Dictionary young physicist. What does it mean: gravity, mass, attraction, particle; Newton's work - light consists of particles
Encyclopedic Dictionary young astronomer. Theories of black holes
News about space and UFOs Pictures and photos depicting black holes
WWalls.RU: desktop wallpaper. Space Pictures and photos of black holes

2.History of the idea
The term “BLACK HOLE” appeared quite recently, in the twentieth century. It was invented by the American scientist John Wheeler.
However, attempts to explain this mysterious phenomenon were made a long time ago, about 200 years ago.
Isaac Newton believed that light consists of particles. This means that it has mass and is affected by gravity.
Based on this, the English astronomer John Michell suggested that such massive stars may exist in nature that even a ray of light is not able to leave their surface.
The great scientist Albert Einstein theoretically proved the possibility of the existence of black holes.
In 1934, American physicists put forward a hypothesis about the dying of a star. And already in 1939 they proved that: “A black hole absorbs everything and releases nothing!”

3.Theories of the emergence of black holes:
How do black holes form (emerge)? There are three theories of the origin of black holes:
1. Collapse of a star under the influence own strength gravity: large stars exist due to their own energy. The star lives until this energy runs out. As the size of a star decreases, its density increases, which leads to an increase in the mass of the star. If the mass of the star is more than three solar, this leads to the collapse of the star.
2. 14 billion years ago the expansion of our Universe began. There is a theory that high densities were observed everywhere at that time. Therefore, small changes in density in that era could lead to the birth of black holes of any mass, including small ones.
3. There is an assumption that black holes can arise from the collision of fast elementary particles. When two particles collide violently, they can be compressed strongly enough to create a microscopic black hole. After this, it will collapse almost instantly.

4.Properties of black holes
1) Time flows slower near a black hole than far from it. If an observer who is at some distance from the black hole throws a luminous object, such as a flashlight, towards the black hole, he will see it fall faster and faster, but then begin to slow down, and its light will dim and turn red. From the point of view of a distant observer, the lantern will practically stop and become invisible, never being able to cross the surface of the black hole. But if the observer himself jumped there along with the lantern, then he would short time fell towards the center of the black hole, being torn apart by its powerful tidal gravitational forces arising from the difference in gravity at different distances from the center. That is, if something (someone) penetrates the event horizon, it will never return.
2) If the body from which the black hole arose rotated, then a “vortex” gravitational field (funnel) is maintained around the black hole, dragging all neighboring bodies into rotational movement around her.
3) When a body is compressed into a black hole, then all its characteristics, except mass, electric charge and angular momentum disappear (such as composition, density, volume, etc.).
4) The boundary of a black hole is called the event horizon. The matter that falls into the event horizon of a black hole will certainly form a singularity (a region of infinitely small sizes) with an immeasurably huge density, due to which all the matter of the star is destroyed.
5) A black hole can “evaporate” very slowly. Stephen Hawking discovered this. They proved that black holes are capable of releasing matter and radiation, but this can only be noticed if the mass of the black hole itself is low enough.
6) A black hole has a huge, inexhaustible supply of energy.

5.Where are black holes located?
The very first question that worries people about the problem of black holes is the desire to find out where black holes are located. In reality, black holes are scattered throughout the Universe. A black hole can form anywhere, including near the solar system.

6.Description of experiments
First experience “Invisible reality”
Imagine that our Earth is the Universe, and everything that is on it (people, animals, plants) are objects of the Universe (i.e. stars, planets, comets). If we close our eyes, we will not see anything, but this does not mean that everything around us has disappeared.
Second experiment “Space distortion”
Take a piece of paper and put two dots. Let's connect the points with a straight line. Determine the distance between points using a ruler. Now let's crumple the sheet. The distance between points has decreased. Thus, we can talk about changes in space inside the black hole.
Third experiment “The color of a black hole”
Let's take two boxes with small round holes. We will paint one inside white and the other black. Let's look through the holes in the boxes. There is nothing visible in both boxes. Let's place objects - they are also not visible. Therefore, we can say that black holes are not necessarily black inside. It follows that black holes are not necessarily black.
8. Conclusions
So, in my opinion, as part of my work, I was able to form an understanding of what a black hole is: I studied the literature, systematized the information received, became acquainted with the history of this issue, examined the properties of black holes and conducted experiments.
Black holes are absolutely amazing objects, unlike anything known so far. These are holes in space and time that arise due to a very strong curvature of space and a change in the nature of the flow of time in a rapidly growing gravitational field. In the future, I want to continue my work on studying these interesting objects, since black holes have enormous energy that can be used for the needs of humanity.

References
1. Hawking S. Three books about space and time. Translation from English – St. Petersburg: Amphora. TID Amphora, 2012. p. 106-109, 123-127, 330-340.
2. KIP S. Thorne. Black holes and folds of time: Einstein's daring legacy. Translation from English Ed. Corresponding member Ran V.B. Braginsky. – M.: Publishing house of physical and mathematical literature, 2009., p. 23, 122-124.
3. Ian Nicholson. Universe. Series “Life of the Planet” - M.: “Rosman”, 2000. p. 21-22.
4. I explore the world: Det. encycl.: Physics / Comp., art. A.A. Leonovich; Under general ed. O. G. Hinn. – M.: OOO Firma Publishing House AST, 1999.
5. I explore the world: Det. encycl.: Space/Aut.- comp. T.I. Gontaruk - M.: LLC Publishing House AST, 1999. p. 355-358.
6. Encyclopedic Dictionary of a Young Physicist. Pedagogy, 1984. p. 286.
7. Encyclopedic Dictionary of a Young Astronomer. Pedagogy, 1986. p. 298-301.
8. News about space and UFOs // Personal website // (access date: 10/15/13)
9. WWalls.RU: wallpaper for your desktop. Space // Personal website // (access date: 10/15/13)

> Black holes

What's happened black hole– explanation for children: description with photos, how to find the Universe in space, how stars appear, the death, supermassive black holes of galaxies.

For the little ones parents or at school should explain that perceiving a black hole as an empty space is a grave mistake. On the contrary, an incredible amount of matter is concentrated in it, which is confined in a small space. To explanation for children was more colorful, just imagine if you took a star 10 times more massive than the Sun and tried to squeeze it into an area the size of New York City. Due to this pressure, the gravitational field becomes so strong that no one, not even a light beam, can escape. With the development of technology, NASA is able to learn more and more about these mysterious objects.

Begin explanation for children This is possible because the term “black hole” did not exist until 1967 (introduced by John Wheeler). But before this, for several centuries it was mentioned about the existence of strange objects that, due to their density and massiveness, do not release light. They were even predicted by Albert Einstein in his general theory of relativity. She proved that when a massive star dies, a small dense core remains. If a star is three times the mass of the sun, then gravity overcomes other forces, and we get a black hole.

Of course it's important explain to the children that researchers are unable to observe these features directly (telescopes only detect light, X-rays and other forms of electromagnetic radiation), so there is no need to wait for a photo of the black hole. But it is possible to calculate their location and even determine their size due to the influence they have on surrounding objects. For example, if it passes through a cloud of interstellar matter, then in the process it will begin to draw matter inward - accretion. The same thing will happen if a star passes nearby. True, a star can explode.

At the moment of attraction, the substance heats up and accelerates, releasing x-rays into space. Recent discoveries have spotted several powerful bursts of gamma rays, demonstrating the hole's devouring of nearby stars. At this moment, they stimulate the growth of some and stop others.

The death of a star is the beginning of a black hole

Most black holes arise from the leftover material of dying large stars (supernova explosions). Smaller stars become dense neutron stars, which lack the massiveness to trap light. If the mass of a star is 3 times greater than that of the Sun, then it becomes a candidate for a black hole. Important explain to the children one oddity. When a star collapses, its surface approaches an imaginary surface (event horizon). Time on the star itself becomes slower than that of the observer. When the surface reaches the event horizon, time freezes and the star can no longer collapse - a frozen, collapsing object.

Larger black holes can appear after a stellar collision. After its launch in December 2004, the NASA telescope was able to detect strong, fleeting flashes of light - gamma rays. Chandra and Hubble then collected data on the event and realized that these flares could be the result of a collision between a black hole and a neutron star, which creates a new black hole.

Although in the process of education children And parents We've already figured it out, but one thing remains a mystery. The holes seem to exist on two different scales. There are many black holes - the remains of massive stars. Typically, they are 10-24 times more massive than the Sun. Scientists constantly see them if an alien star comes critically close. But most black holes exist in isolation and simply cannot be seen. However, judging by the number of stars large enough to be black hole candidates, there must be tens of millions of billions of such black holes in the Milky Way.

There are also supermassive black holes, which are a million or even a billion times larger than our Sun. It is believed that such monsters live in the centers of almost all large galaxies (including ours).

For the little ones it will be interesting to know that for a long time Scientists believed that there was no average size for black holes. But data from Chandra, XMM-Newton and Hubble show that they are there.

It is possible that supermassive black holes arise from a chain reaction caused by the collision of stars in compact clusters. Because of this, a lot of massive stars accumulate, which collapse and produce black holes. These clusters then occupy the galactic center, where the black holes merge and become a supermassive member.

You might already understand that you won't be able to admire the black hole in high quality online because these objects do not release light. But children will be interested in studying photographs and diagrams created based on the contact of black holes and ordinary matter.

Space objects

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Concept black hole known to everyone - from schoolchildren to people old age, it is used in science and fiction literature, in tabloid media and on scientific conferences. But what exactly such holes are is not known to everyone.

From the history of black holes

1783 The first hypothesis of the existence of such a phenomenon as a black hole was put forward in 1783 by the English scientist John Michell. In his theory, he combined two of Newton's creations - optics and mechanics. Michell's idea was this: if light is a stream of tiny particles, then, like all other bodies, the particles should experience the attraction of a gravitational field. It turns out that the more massive the star, the more difficult it is for light to resist its attraction. 13 years after Michell, the French astronomer and mathematician Laplace put forward (most likely independently of his British colleague) a similar theory.

1915 However, all their works remained unclaimed until the beginning of the 20th century. In 1915, Albert Einstein published the General Theory of Relativity and showed that gravity is the curvature of spacetime caused by matter, and a few months later, German astronomer and theoretical physicist Karl Schwarzschild used it to solve a specific astronomical problem. He explored the structure of curved space-time around the Sun and rediscovered the phenomenon of black holes.

(John Wheeler coined the term "Black holes")

1967 American physicist John Wheeler outlined a space that can be crumpled, like a piece of paper, into an infinitesimal point and designated it with the term “Black Hole”.

1974 British physicist Stephen Hawking proved that black holes, although they absorb matter without return, can emit radiation and eventually evaporate. This phenomenon is called “Hawking radiation”.

Our time. Latest research pulsars and quasars, as well as the discovery cosmic microwave background radiation, finally made it possible to describe the very concept of black holes. In 2013, the G2 gas cloud came very close close distance to the Black Hole and will most likely be absorbed by it, observations of the unique process will provide enormous opportunities for new discoveries of the features of black holes.

What black holes actually are

A laconic explanation of the phenomenon goes like this. A black hole is a space-time region whose gravitational attraction is so strong that no object, including light quanta, can leave it.

The black hole was once a massive star. While thermonuclear reactions are maintained in its depths high blood pressure, everything remains normal. But over time, the energy supply is depleted and celestial body, under the influence of its own gravity, begins to compress. The final stage of this process is the collapse of the stellar core and the formation of a black hole.

1. A black hole ejects a jet at high speed

2. A disk of matter grows into a black hole

3. Black hole

4. Detailed diagram of the black hole region

5. Size of new observations found

The most common theory is that similar phenomena exist in every galaxy, including the center of ours. milky way. The huge gravitational force of the hole is capable of holding several galaxies around it, preventing them from moving away from each other. The “coverage area” can be different, it all depends on the mass of the star that turned into a black hole, and can be thousands of light years.

Schwarzschild radius

The main property of a black hole is that any substance that falls into it can never return. The same applies to light. At their core, holes are bodies that completely absorb all light falling on them and do not emit any of their own. Such objects may visually appear as clots of absolute darkness.

1. Moving matter at half the speed of light

2. Photon ring

3. Inner photon ring

4. Event horizon in a black hole

Starting from General theory According to Einstein's relativity, if a body approaches a critical distance to the center of the hole, it will no longer be able to return. This distance is called the Schwarzschild radius. What exactly happens inside this radius is not known for certain, but there is the most common theory. It is believed that all the matter of a black hole is concentrated in an infinitesimal point, and at its center there is an object with infinite density, which scientists call a singular disturbance.

How does falling into a black hole happen?

(In the picture, the black hole Sagittarius A* looks like an extremely bright cluster of light)

Not so long ago, in 2011, scientists discovered a gas cloud, giving it the simple name G2, which emits unusual light. This glow may be due to friction in the gas and dust caused by the Sagittarius A* black hole, which orbits it as an accretion disk. Thus, we become observers of the amazing phenomenon of absorption of a gas cloud by a supermassive black hole.

According to recent studies, the closest approach to the black hole will occur in March 2014. We can recreate a picture of how this exciting spectacle will take place.

1. When first appearing in the data, a gas cloud resembles a huge ball of gas and dust.

2. Now, as of June 2013, the cloud is tens of billions of kilometers from the black hole. It falls into it at a speed of 2500 km/s.

3. The cloud is expected to pass by the black hole, but tidal forces caused by the difference in gravity acting on the leading and trailing edges of the cloud will cause it to take on an increasingly elongated shape.

4. After the cloud is torn apart, most of it will most likely flow into the accretion disk around Sagittarius A*, giving rise to shock waves. The temperature will jump to several million degrees.

5. Part of the cloud will fall directly into the black hole. No one knows exactly what will happen to this substance next, but it is expected that as it falls it will emit powerful streams of X-rays and will never be seen again.

Video: black hole swallows a gas cloud

(Computer simulation of how most gas cloud G2 will be destroyed and absorbed by the black hole Sagittarius A*)

What's inside a black hole?

There is a theory that states that a black hole is practically empty inside, and all its mass is concentrated in an incredibly small point located at its very center - the singularity.

According to another theory, which has existed for half a century, everything that falls into a black hole passes into another universe located in the black hole itself. Now this theory is not the main one.

And there is a third, most modern and tenacious theory, according to which everything that falls into a black hole dissolves in the vibrations of strings on its surface, which is designated as the event horizon.

So what is an event horizon? It is impossible to look inside a black hole even with a super-powerful telescope, since even light, entering the giant cosmic funnel, has no chance of emerging back. Everything that can be at least somehow considered is located in its immediate vicinity.

The event horizon is a conventional surface line from under which nothing (neither gas, nor dust, nor stars, nor light) can escape. And this is the very mysterious point of no return in the black holes of the Universe.

The worst place.

There is no more mysterious and frightening object in space than a black hole.
One phrase already evokes unaccountable fear: it paints an image of an all-consuming abyss. Not only ordinary people are shy before her, but astrophysicists are also in awe. “Of all the creations of the human mind: from mythological unicorns and dragons to hydrogen bomb, perhaps the most fantastic is a black hole. A hole in space with very specific edges, into which anything can fall and from which nothing can get out. A hole in which the gravitational force is so great that even light is captured and trapped within it. A hole that bends space and distorts the flow of time. Like unicorns and dragons, black holes seem more like attributes of science fiction or ancient myths than real objects. However, physical laws inevitably imply the existence of black holes. In our Galaxy alone, there are perhaps millions of them,” said the famous scientist, head of the department at the California Institute of Technology (USA), member of the US National Academy of Sciences, member of the NASA Scientific Council, Kip Stephen Thorne, about black holes.
In addition to their fantastic power, black holes have amazing property change space and time within yourself. They first twist into a kind of funnel, and then, having crossed a certain boundary in the depths of the hole, they disintegrate into quanta. Inside the black hole, beyond the edge of this peculiar gravitational abyss, from where there is no exit, amazing physical processes flow and new laws of nature appear.
According to many experts, black holes are the most enormous sources of energy in the Universe. We probably see them in distant quasars, in the exploding cores of galaxies. It is assumed that black holes will become energy sources for humanity in the future.

The end of the world is here.

How do black holes form? According to astrophysicists, most of them occur after death big stars. If a star has twice the mass of the Sun, then towards the end of its life the star may explode as a supernova. But if the mass of the matter remaining after the explosion still exceeds two solar masses, then the star should collapse into a tiny dense body, since gravitational forces completely suppress any internal resistance to compression. Scientists believe that it is at this moment that a catastrophic gravitational collapse leads to the emergence of a black hole. They believe that with the end of thermonuclear reactions, the star can no longer be in a stable state. Then for a massive star there remains one inevitable path - the path of general and complete compression, turning it into an invisible black hole.
Why are they invisible?
“The very name “black holes” suggests that this is a class of objects that cannot be seen,” explains the head of the radio astronomy department of the State Astronomical Institute. Sternberg candidate of physical and mathematical sciences Valentin Esipov. - Their gravitational field is so strong that if somehow it was possible to get close to a black hole and direct the beam of the most powerful searchlight away from its surface, then it would be impossible to see this searchlight even from a distance not exceeding the distance from the Earth to the Sun.
Indeed, even if we could concentrate all the light of the Sun in this powerful spotlight, we would not see it, since the light would not be able to overcome the influence of the black hole’s gravitational field on it and leave its surface. That is why such a surface is called the absolute event horizon. It represents the boundary of a black hole. What is hiding there, abroad?

Let's walk to Hell.

The most interesting description The “insides” of the black hole belong to the already mentioned American physicist and astronomer Kip Stephen Thorne. "Imagine yourself the captain of a big spaceship stellar class,” the scientist suggests in his book “Journey Among Black Holes.” - On assignment Geographical Society you will have to explore several black holes located at great distances from each other in interstellar space, and use radio signals to transmit a description of your observations to Earth.

Having been on the road for 4 years and 8 months, your ship slows down in the vicinity of the black hole closest to Earth, called Hades (Hell) and located near the star Vega. The presence of a black hole is noticeable on the television screen: hydrogen atoms scattered in interstellar space are drawn inside by its gravitational field. Everywhere you see their movement: slow away from the hole and increasingly faster as you approach it. It's like the falling water at Niagara Falls, except that the atoms are falling not only from the east, but also from the west, north, south, above and below - everywhere. If you don't do anything, you too will be pulled in.

So, you have to carefully move the starship from a free-fall trajectory into a circular orbit around the black hole (similar to the orbits of artificial satellites orbiting the Earth) so that the centrifugal force of your orbital motion compensates for the gravitational force of the black hole. Feeling safe, you turn on the ship's engines and prepare to explore the black hole.

First of all, through telescopes you observe electromagnetic radiation emitted by falling hydrogen atoms. Far from the black hole, they are so cold that they only emit radio waves. But closer to the hole, where the atoms fall faster, they collide with each other from time to time, heat up to several thousand degrees and begin to emit light. Even closer to the black hole, moving much faster, they heat up to several million degrees due to collisions and emit X-rays.

As you point your telescopes "inward" and continue to approach the black hole, you will "see" gamma rays emitted by hydrogen atoms heated to even higher temperatures. high temperatures. And finally, in the very center you will find the dark disk of the black hole itself.
Your next step is to carefully measure the length of the ship's orbit. This is approximately 1 million km, or half the length of the Moon's orbit around the Earth. Then you look at the distant stars and see that they are moving like you. Watching them visible movement, you find out that you need 5 minutes. 46 s to complete one revolution around a black hole. This is your “orbital period”.

Knowing its orbital period and the length of its orbit, you can calculate the mass of the Hades (Hell) black hole. It will be 10 times larger than the sun. This is, in essence, the total mass accumulated in a black hole over its entire history and includes the mass of the star, as a result of the collapse of which about 2 billion years ago the black hole was formed, the mass of all interstellar hydrogen drawn into it since its birth, and also the mass of all the asteroids and stray starships that fell on it.

Most interesting are the properties of its surface, or horizon - the boundary due to which anything that falls into the hole cannot return. Borders from which a starship and even any type of radiation cannot escape: radio waves, light, x-rays or gamma rays...
Although you can figure out all the properties of a black hole from the mass and angular momentum of a black hole, you can't figure out anything about its interior. It may have a disordered structure and be highly asymmetrical. All this will depend on the details of the collapse that resulted in the formation of the black hole, as well as on the characteristics of the subsequent retraction of interstellar hydrogen. So the diameter of the hole simply cannot be calculated.

Once you have these results, you can explore the vicinity of the black hole's horizon...

After saying goodbye to the team, you climb into the descent module and leave the ship, initially remaining in the same circular orbit, continues physicist Thorne. - Then, turning on the rocket engine, brake slightly to slow down your orbital movement. At the same time, you begin to spiral closer to the horizon, moving from one circular orbit to another. Your goal is to enter a circular orbit with a perimeter slightly greater than the length of the horizon. As you move in a spiral, the length of your orbit gradually decreases - from 1 million km to 500 thousand, then to 100 thousand, 90 thousand, 80 thousand. And then something strange begins to happen.

Being in a state of weightlessness, you are suspended in your apparatus, let’s say, with your feet to the black hole, and your head to the orbit of your ship and the stars. But gradually you begin to feel that someone is pulling you down by your legs and up by your head. You realize that the reason is the gravity of the black hole: the legs are closer to the hole than the head, so they are attracted more strongly. The same is true, of course, on Earth, but the difference in the attraction of the legs and head there is negligible, so no one notices it. Moving in an orbit 80 thousand km long above a black hole, you feel this difference quite clearly - the difference in gravity will be 1/8 of the earth's gravity (1/8 g). The centrifugal force caused by your orbital motion will compensate for the pull of the hole at the center point of your body, allowing you to float freely in zero gravity, but your legs will be subject to an excess pull of 1/16 g, while your head will be pulled weakly, and the centrifugal force will pull it up with exactly the same additional acceleration - 1/16 g.
Somewhat puzzled, you continue to move along the twisting spiral, but surprise quickly gives way to concern: as the size of the orbit decreases, the forces stretching you will increase more and more rapidly. With an orbit length of 64 thousand km the difference will be 1/4 g, at 51 thousand km - 1/2 g and at 40 thousand km it will reach the full weight of the Earth. Grinding your teeth from the effort, you continue to move in a spiral. With an orbit length of 25 thousand km, the stretching force will be 4 g, i.e. will be four times your weight in terrestrial conditions, and at 16 thousand km - 16 g. You can no longer stand in an upright position. You try to solve this problem by curling up and pulling your legs towards your head, thereby reducing the difference in force. But they are already so large that they will not allow you to bend - they will again stretch you vertically (along the direction radial to the black hole).

No matter what you do, nothing will help. And if the spiral movement continues, your body will not be able to withstand it - it will be torn apart. So, there is no hope of reaching the vicinity of the horizon...
Broken, overcoming monstrous pain, you stop your descent and transfer the device first into a circular orbit, and then begin to carefully and slowly move along an expanding spiral, moving into circular orbits all the time larger size until you reach the starship."

The story told by Thorne still sounds like science fiction. And it is designed for the time when man will achieve such success in the development of technology and technology that intergalactic flights and the construction of ring worlds around black holes will become a reality. And according to the most optimistic forecasts of futurologists, this will become possible no earlier than in 50 years.

No guys, it's not like that...

It must be admitted that many scientists still deny the existence of black holes. After all, their discovery and study occurs at the tip of the pen. And recently, an even more unexpected suggestion appeared that black holes are not holes at all, but some objects more similar in nature to bubbles of Bose-Einstein condensate ( physical state matter, the basis of which is bosons cooled to temperatures close to absolute zero). This new hypothesis put forward by researcher Emil Mottola from the Theoretical Division of Los Alamos National Laboratory along with co-author Pavel Mazur from South Carolina State University in the USA.

The researchers' explanation brings a radical new perspective to the nature of black holes, which are not seen as "holes" in space where matter and light inexplicably disappear at the event horizon, but rather as spherical voids surrounded by a special form of matter never before known on Earth. Mazur and Mottola call these objects not black holes, but gravitational stars.

Inside a gravitational star, space and time are reversed, just as in the black hole model.
Mottola and Mazur even suggest that the Universe in which we live may be inner shell giant gravitational star.