For publication work with basic equations general theory relativity (GR). Later it became clear that the new theory of gravity, which turns 100 years old in 2015, predicts the existence of black holes and space-time tunnels. Lenta.ru will tell about them.
What is OTO
General relativity is based on the principles of equivalence and general covariance. First ( weak principle) means the proportionality of the inertial (associated with motion) and gravitational (associated with gravitation) masses and allows (strong principle) in a limited region of space not to distinguish between the gravitational field and motion with acceleration. Classic example- elevator. With its uniformly accelerated upward movement relative to the Earth, the observer located in it is not able to determine whether he is in a stronger gravitational field or moves in a man-made object.
The second principle (general covariance) assumes that the GR equations preserve their form under transformations special theory relativity created by Einstein and other physicists by 1905. The ideas of equivalence and covariance led to the need to consider a single space-time, which is curved in the presence of massive objects. This distinguishes general relativity from Newton's classical theory of gravity, where space is always flat.
General relativity in four dimensions includes six independent partial differential equations. To solve them (finding an explicit form of the metric tensor describing the curvature of space-time), it is necessary to set the boundary and coordinate conditions, as well as the energy-momentum tensor. The latter describes the distribution of matter in space and, as a rule, is associated with the equation of state used in the theory. In addition, the GR equations allow the introduction of a cosmological constant (lambda term), which is often associated with dark energy and, probably, the scalar field corresponding to it.
Black holes
In 1916, the German mathematical physicist Karl Schwarzschild found the first solution to the GR equations. It describes the gravitational field created by a centrally symmetric mass distribution with zero electric charge. This solution contained the so-called gravitational radius of the body, which determines the dimensions of an object with a spherically symmetric distribution of matter, which photons (quanta moving at the speed of light) are not able to leave. electro magnetic field).
The Schwarzschild sphere defined in this way is identical to the concept of the event horizon, and the massive object limited by it is identical to the concept of a black hole. The perception of a body approaching it within the framework of general relativity differs depending on the position of the observer. For an observer connected with the body, reaching the Schwarzschild sphere will occur in a finite proper time. For an external observer, the approach of the body to the event horizon will take infinite time and will look like its unlimited fall onto the Schwarzschild sphere.
Soviet theoretical physicists also contributed to the theory of neutron stars. In the 1932 article "On the Theory of Stars", Lev Landau predicted the existence of neutron stars, and in the work "On the Sources of Stellar Energy", published in 1938 in the journal Nature, he suggested the existence of stars with a neutron core.
How do massive objects turn into black holes? The conservative and currently most recognized answer to this question was given in 1939 by theoretical physicists Robert Oppenheimer (in 1943 he became the scientific director of the Manhattan Project, under which the world's first atomic bomb was created in the United States) and his graduate student Hartland Snyder.
In the 1930s, astronomers became interested in the question of the future of a star if its interior ran out of nuclear fuel. For small stars like the Sun, evolution will lead to the transformation into white dwarfs, in which the gravitational contraction force is balanced by the electromagnetic repulsion of the electron-nuclear plasma. In heavier stars, gravity is stronger than electromagnetism, and neutron stars are formed. The core of such objects is made of a neutron liquid, and it is covered by a thin plasma layer of electrons and heavy nuclei.
Image: East News
The limit value of the mass of a white dwarf, which prevents it from turning into a neutron star, was first estimated in 1932 by the Indian astrophysicist Subramanyan Chandrasekhar. This parameter is calculated from the equilibrium condition for the degenerate electron gas and gravitational forces. Modern meaning Chandrasekhar limit is estimated at 1.4 solar mass.
Upper weight limit neutron star, at which it does not turn into a black hole, is called the Oppenheimer-Volkov limit. It is determined from the equilibrium condition for the degenerate neutron gas pressure and gravitational forces. In 1939, a value of 0.7 solar masses was obtained, modern estimates vary from 1.5 to 3.0.
Mole Hole
Physically, a wormhole (wormhole) is a tunnel connecting two distant regions of space-time. These regions may be in the same universe, or they may link different points different universes (within the concept of the multiverse). Depending on the ability to return through the hole, they are divided into passable and impassable. Impassable holes quickly close and do not allow a potential traveler to make the return trip.
From a mathematical point of view, a wormhole is a hypothetical object obtained as a special non-singular (finite and having a physical meaning) solution of the GR equations. Wormholes are usually depicted as a bent two-dimensional surface. You can get from one side of it to the other both in the usual way and through the tunnel connecting them. In the visual case of a two-dimensional space, it can be seen that this can significantly reduce the distance.
In 2D, wormhole throats - the openings from which the tunnel begins and ends - have the shape of a circle. In three dimensions, the mouth of a wormhole looks like a sphere. Such objects are formed from two singularities in different regions of space-time, which in hyperspace (space of higher dimension) are drawn together to form a hole. Since the hole is a space-time tunnel, you can travel through it not only in space, but also in time.
For the first time solutions of GR equations of the wormhole type were given in 1916 by Ludwig Flamm. His work, which described a wormhole with a spherical neck without gravitating matter, did not attract the attention of scientists. In 1935, Einstein and the American-Israeli theoretical physicist Nathan Rosen, unfamiliar with Flamm's work, found a similar solution to the GR equations. They were driven in this work by the desire to combine gravity with electromagnetism and get rid of the singularities of the Schwarzschild solution.
In 1962, American physicists John Wheeler and Robert Fuller showed that the Flamm wormhole and the Einstein-Rosen bridge collapse rapidly and are therefore impassable. The first solution to the GR equations with a traversable wormhole was proposed in 1986 by the American physicist Kip Thorne. Its wormhole is filled with matter with a negative average mass density that prevents the tunnel from closing. Elementary particles with such properties are still unknown to science. Probably, they can be part of dark matter.
Gravity today
The Schwarzschild solution is the simplest for black holes. Rotating and charged black holes have already been described. consistent mathematical theory black holes and their associated singularities was developed in the work of the British mathematician and physicist Roger Penrose. As early as 1965, he published an article in the journal Physical Review Letters titled "Gravity Collapse and Space-Time Singularities".
It describes the formation of the so-called trap surface, leading to the evolution of a star into a black hole and the emergence of a singularity - a feature of space-time, where the GR equations give solutions that are incorrect from a physical point of view. Penrose's conclusions are considered the first major mathematically rigorous result of general relativity.
Shortly thereafter, the scientist, together with Briton Stephen Hawking, showed that in the distant past the universe was in a state of infinite mass density. The singularities that arise in general relativity and are described in the works of Penrose and Hawking defy explanation in modern physics. In particular, this leads to the impossibility of describing nature before the Big Bang without involving additional hypotheses and theories, for example, quantum mechanics and string theory. The development of the theory of wormholes is also currently impossible without quantum mechanics.
It is curved, and gravity, familiar to all of us, is a manifestation of this property. Matter bends, "bends" the space around itself, and the more, the denser it is. Cosmos, space and time are all very interesting topics. After reading this article, you will surely learn something new about them.
The idea of curvature
Many other theories of gravitation, of which there are hundreds today, differ in details from general relativity. However, all these astronomical hypotheses retain the main thing - the idea of curvature. If space is curved, then we can assume that it could take, for example, the shape of a pipe connecting areas that are separated by many light years. And perhaps even eras far from each other. After all, we are not talking about the space that is familiar to us, but about space-time when we consider the cosmos. A hole in it can appear only under certain conditions. We invite you to take a closer look at such an interesting phenomenon as wormholes.
First ideas about wormholes
Deep space and its mysteries beckon. Thoughts about curvature appeared immediately after GR was published. L. Flamm, an Austrian physicist, already in 1916 said that spatial geometry can exist in the form of a kind of hole that connects two worlds. The mathematician N. Rosen and A. Einstein in 1935 noticed that the simplest solutions of equations in the framework of general relativity, describing isolated electrically charged or neutral sources that create, have a spatial structure of a "bridge". That is, they connect two universes, two almost flat and identical space-times.
Later, these spatial structures became known as "wormholes", which is a rather loose translation from of English language word wormhole. A closer translation of it is "wormhole" (in space). Rosen and Einstein did not even rule out the possibility of using these "bridges" to describe elementary particles with their help. Indeed, in this case the particle is a purely spatial formation. Therefore, there is no need to specifically model the source of charge or mass. And a distant external observer, if the wormhole has microscopic dimensions, sees only a point source with a charge and mass while in one of these spaces.
Bridges Einstein-Rosen
On the one hand, electrical lines of force enter the hole, and on the other they exit, without ending or starting anywhere. J. Wheeler, an American physicist, said on this occasion that "charge without charge" and "mass without mass" are obtained. It is not at all necessary in this case to consider that the bridge serves to connect two different universes. No less appropriate would be the assumption that at the wormhole both "mouths" go out into the same universe, however, in different times and at different points. It turns out something resembling a hollow "handle", if it is sewn to an almost flat familiar world. The lines of force enter the mouth, which can be understood as a negative charge (let's say an electron). The mouth from which they exit is positive charge(positron). As for the masses, they will be the same on both sides.
Conditions for the formation of "bridges" Einstein-Rosen
This picture, for all its attractiveness, did not become widespread in elementary particle physics, for which there were many reasons. It is not easy to attribute quantum properties to the Einstein-Rosen "bridges", which are indispensable in the microworld. Such a "bridge" does not form at all when known values charges and masses of particles (protons or electrons). The "electrical" solution instead predicts a "naked" singularity, that is, a point where electric field and the curvature of space become infinite. At such points, the concept of space-time, even in the case of curvature, loses its meaning, since it is impossible to solve equations that have an infinite number of terms.
When does OTO not work?
By itself, GR definitely states exactly when it stops working. On the neck, in the most bottleneck"bridge", there is a violation of the smoothness of the connection. And it must be said that it is rather nontrivial. From the position of a distant observer, time stops at this neck. What Rosen and Einstein thought was the throat is now defined as the event horizon of a black hole (whether charged or neutral). rays or particles different parties"bridges" fall on different "sections" of the horizon. And between its left and right parts, relatively speaking, there is a non-static area. In order to pass the area, it is impossible not to overcome it.
Inability to pass through a black hole
A spacecraft approaching the horizon of a relatively large black hole seems to freeze forever. Less and less often, signals from it reach ... On the contrary, the horizon according to the ship's clock is reached in a finite time. When a ship (a beam of light or a particle) passes it, it will soon run into a singularity. This is where the curvature becomes infinite. In the singularity (still on the way to it), the extended body will inevitably be torn and crushed. This is the reality of the black hole.
Further research
In 1916-17. Reisner-Nordström and Schwarzschild solutions were obtained. They describe symmetrical electrically charged and neutral black holes spherically. However, physicists were able to fully understand the complex geometry of these spaces only at the turn of the 1950s and 60s. It was then that D. A. Wheeler, known for his work in the theory of gravity and nuclear physics, proposed the terms "wormhole" and "black hole". It turned out that in the spaces of Reisner-Nordström and Schwarzschild there really are wormholes in space. They are completely invisible to a distant observer, like black holes. And, like them, wormholes in space are eternal. But if the traveler penetrates beyond the horizon, they collapse so quickly that neither a ray of light nor a massive particle, let alone a ship, can fly through them. To fly to another mouth, bypassing the singularity, you need to move faster than light. At present, physicists believe that supernova velocities of energy and matter are fundamentally impossible.
Schwarzschild and Reisner-Nordstrom
The Schwarzschild black hole can be considered an impenetrable wormhole. As for the Reisner-Nordström black hole, it is somewhat more complicated, but also impassable. Still, it's not that hard to come up with and describe four-dimensional wormholes in space that could be traversed. It's just a matter of picking required view metrics. The metric tensor, or metric, is a set of values that can be used to calculate the four-dimensional intervals that exist between event points. This set of quantities fully characterizes both the gravitational field and the space-time geometry. Geometrically traversable wormholes in space are even simpler than black holes. They do not have horizons that lead to cataclysms with the passage of time. At different points, time can go at a different pace, but it should not stop or speed up indefinitely.
Two directions of wormhole research
Nature has put a barrier in the way of the appearance of wormholes. However, a person is arranged in such a way that if there is an obstacle, there will always be those who want to overcome it. And scientists are no exception. The works of theorists who are engaged in the study of wormholes can be conditionally divided into two areas that complement each other. The first deals with the consideration of their consequences, assuming in advance that wormholes do exist. Representatives of the second direction are trying to understand from what and how they can appear, what conditions are necessary for their occurrence. There are more works in this direction than in the first one and, perhaps, they are more interesting. This area includes the search for models of wormholes, as well as the study of their properties.
Achievements of Russian physicists
As it turned out, the properties of matter, which is the material for the construction of wormholes, can be realized due to the polarization of the vacuum of quantum fields. Russian physicists Sergei Sushkov and Arkady Popov, together with the Spanish researcher David Hochberg, and Sergei Krasnikov, recently came to this conclusion. The vacuum in this case is not a void. This is a quantum state characterized by the lowest energy, that is, a field in which there are no real particles. In this field, pairs of “virtual” particles constantly appear, disappearing before they are detected by devices, but leaving their mark in the form of an energy tensor, that is, an impulse characterized by unusual properties. Despite the fact that the quantum properties of matter are mainly manifested in the microcosm, the wormholes generated by them, under certain conditions, can reach significant sizes. One of Krasnikov's articles, by the way, is called "The Threat of Wormholes."
A question of philosophy
If wormholes are ever built or discovered, the field of philosophy concerned with the interpretation of science will face new challenges, and, it must be said, very difficult ones. For all the seemingly absurdity of time loops and the hard problems of causality, this area of science will probably figure it out someday. Just as the problems of quantum mechanics and the created Cosmos, space and time were dealt with in their time - all these questions have interested people in all ages and, apparently, will always interest us. It is almost impossible to know them completely. Space exploration is unlikely to ever be completed.
A wormhole is a theoretical passage through space-time that can greatly reduce long-distance travel across the universe by creating shortest paths between destinations. The existence of wormholes is predicted by the theory of relativity. But along with convenience, they can also carry extreme dangers: the danger of a sudden collapse, high radiation and dangerous contacts with exotic matter.
The theory of wormholes, or "wormholes"
In 1935, physicists Albert Einstein and Nathan Rosen proposed the existence of "bridges" in space-time using the theory of relativity. These paths, called Einstein-Rosen bridges or wormholes ("wormholes"), connect two different points in space-time, theoretically creating the shortest corridors that reduce distance and travel time.
Wormholes have, as it were, two mouths connected by a common neck. The mouths most likely have a spherical shape. The throat may be a straight section, but it may also twist, becoming longer the longer the normal route.
Einstein's general theory of relativity mathematically predicts the existence of "wormholes" (wormholes), but none have been discovered to date. A wormhole with negative mass can be tracked down due to the effect of its gravity on light passing by.
Some solutions of the general theory of relativity allow the existence of "wormholes", each entrance (mouth) of which is a black hole. However, natural black holes formed as a result of the collapse dying star, by themselves do not create a wormhole.
Through a wormhole
Science fiction is replete with stories of travel through wormholes. But in reality, such journeys are much more difficult, and not only because we must first find such a wormhole.
The first problem is size. Relic wormholes are believed to exist on a microscopic level, about 10 -33 centimeters in diameter. However, as the Universe expands, it is possible that some of them have grown to large sizes.
Another problem arises from stability. More precisely, because of its absence. The wormholes predicted by Einstein-Rosen would be useless for travel because they collapse too quickly. But more recent research has shown that wormholes containing "exotic matter" can remain open and unchanged for longer periods of time.
Exotic matter, not to be confused with dark matter or antimatter, has a negative density and a huge negative pressure. Such matter can only be found in the behavior of certain vacuum states within the framework of quantum field theory.
If wormholes contain enough exotic matter, whether naturally occurring or artificially added, then in theory they could be used as a means of transmitting information or a corridor through space.
Not only can wormholes connect two different ends of the same universe, they could also connect two different universes. Also, some scientists have suggested that if one wormhole entrance moves in a certain way, it could be useful for time travel . However, their opponents, such as the British cosmologist Stephen Hawking, argue that such a use is not possible.
While adding exotic matter to a wormhole could stabilize it to the point where humans could safely travel through it, there is still the possibility that adding "regular" matter would be enough to destabilize the portal.
Current technology is not enough to enlarge or stabilize wormholes, even if they are found soon. However, scientists continue to explore this notion as a method of space travel, with the hope that the technology will eventually emerge and they will eventually be able to use wormholes.
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Wormhole or wormhole in theory is the intersection of time and space, which significantly reduces the time of long-distance travel throughout the universe. The concept of "wormhole" was born thanks to the general theory of relativity. Wormholes have not yet been studied and carry a colossal danger in the form of sudden contacts with unexplored matters, high radiation and other unknown collapses.
Wormhole theory
In the recent 1935, physicists and Nathan Rosen discovered the theory of general relativity, which suggested the existence of "bridges" through space and time. These paths are called "Einstein-Rosen bridges" or wormholes. These bridges connect two different points in time and space, theoretically creating a path that reduces travel time and travel distance.
In theory, it contains two holes, which are then connected. The beginnings of these holes are most likely spherical. Then, they move into a straight section, although perhaps it can form a circle, providing the traveler with a longer path than the traditional way.
Einstein's theory of general relativity mathematically suggests the existence of wormholes, but to date, none have been discovered by astrophysicists. The only suggestion of a KN is the negative mass, which can be detected due to how its gravity affects the light passing by.
Some of the statements of general relativity allow for the existence of wormholes, some of which are made up of black holes. True, by its very nature, a black hole that occurs when a dying star explodes cannot by itself create a wormhole.
Science fiction is replete with tales of travel through wormholes. But the actual reality of such a journey does not yet seem real.
The first problem is the size of the wormholes. Ordinary wormholes, according to scientists, have a size of 10-33 centimeters. However, as the Universe expands, it is possible that some of them could stretch to large sizes.
Another problem for travelers comes from the unexplored stability of the wormhole. The Einstein-Rosen studies were simply useless for practical travel. But more recent research has shown that a wormhole containing "exotic matter" can remain open to research and unchanged for long periods of time.
Exotic matter, which is different from dark matter or antimatter, contains negative energy density as well as negative pressure.
If a wormhole contains enough exotic matter, be it naturally occurring or artificially engineered material, it could theoretically be used as a way to send information or travelers through space.
Wormholes can not only connect two separate regions of the universe, but they can also connect two different galaxies. Interestingly, some scholars suggest that if one entrance to the NE moves in a certain learned order, then this may subsequently allow for travel. Despite this, British astrophysicist and cosmologist Stephen Hawking argues that the use of KN for travel is not yet possible.
"A wormhole doesn't really give you the ability to travel back in time," wrote NASA employee Eric Christian.
Mole Hole. What is a "Wormhole"?
The hypothetical "Wormhole", which is also called a "molehole" or "wormhole" (literal translation of Wormhole) is a kind of space-time tunnel that allows an object to move from point a to point b in the universe not in a straight line, but around space. In the event that it is easier, then take any piece of paper, fold it in half and pierce it, the resulting hole will be the same wormhole
. So there is a theory that the space in the universe can be conditionally the same sheet of paper, attention, only adjusted for the third dimension. Various scientists deduce hypotheses that thanks to wormholes travel in space - time is possible. But at the same time, no one knows exactly what dangers wormholes can pose and what can actually be on the other side of them.
Theory of wormholes.
In 1935, physicists Albert Einstein and Nathan Rosen, using the general theory of relativity, suggested that there are special "bridges" across space-time in the universe. These paths, called Einstein-Rosen bridges (or wormholes), connect two completely different points in space-time by theoretically creating a curvature in space that shortens travel from one point to another.
Again, hypothetically, any wormhole consists of two entrances and a neck (that is, the same tunnel. In this case, most likely, the entrances at the wormhole are spheroidal in shape, and the neck can represent both a straight segment of space and a spiral one.
Traveling through a wormhole.
The first problem that will stand in the way of the possibility of such travel is the size of wormholes. It is believed that the very first wormholes were very small size, about 10-33 centimeters, but due to the expansion of the universe, it became possible that the wormholes themselves expanded and increased along with it. Another problem with wormholes is their stability. Or rather, instability.
Explained by the Einstein-Rosen theory, wormholes will be useless for space-time travel because they collapse (close) very quickly. But more recent research on these issues implies the presence of "Exotic Matter", which allows holes to maintain their structure for a longer period of time.
And yet, theoretical science believes that if wormholes contain enough of this exotic energy, which either appeared naturally or will appear artificially, then it will be possible to transfer information or even objects through space-time.
The same hypotheses suggest that wormholes can connect not only two points within one universe, but also be the entrance to others. Some scientists believe that if one wormhole entrance is moved in a certain way, then time travel will be possible. But, for example, the famous British cosmologist Stephen Hawking believes that such use of wormholes is impossible.
Nevertheless, some scientific minds insist that if stabilization of wormholes by exotic matter is indeed possible, then it will be possible for people to safely travel through such wormholes. And due to the "Ordinary" matter, if desired and necessary, such portals can be destabilized back.
According to the theory of relativity, nothing can travel faster than light. This means that nothing can get out of this gravitational field by getting into it. The region of space from which there is no way out is called a black hole. Its boundary is determined by the trajectory of light rays, which were the first to lose the opportunity to break out. It is called the event horizon of a black hole. Example: looking out of the window, we do not see what is beyond the horizon, and the conditional observer cannot understand what is happening inside the boundaries of an invisible dead star.
Physicists have found signs of the existence of another universe
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There are five types of black holes, but it is the stellar-mass black hole that interests us. Such objects are formed at the final stage of the life of a celestial body. In general, the death of a star can result in the following things:
1. It will turn into a very dense extinct star, consisting of a series chemical elements, is a white dwarf;
2. Into a neutron star - has an approximate mass of the Sun and a radius of about 10-20 kilometers, inside it consists of neutrons and other particles, and outside it is enclosed in a thin but solid shell;
3. Into a black hole, the gravitational attraction of which is so strong that it can suck in objects flying at the speed of light.
When a supernova occurs, that is, the "rebirth" of a star, a black hole is formed, which can only be detected due to the emitted radiation. It is she who is able to generate a wormhole.
If we imagine a black hole as a funnel, then the object, having fallen into it, loses the event horizon and falls inward. So where is the wormhole? It is located in exactly the same funnel, attached to the tunnel of a black hole, where the exits face outward. Scientists believe that the other end of the wormhole is connected to a white hole (the antipode of a black one, into which nothing can fall).
Mole Hole. Schwarzschild and Reisner-Nordström black holes
The Schwarzschild black hole can be considered an impenetrable wormhole. As for the Reisner-Nordström black hole, it is somewhat more complicated, but also impassable. Still, it's not that hard to come up with and describe four-dimensional wormholes in space that could be traversed. You just need to choose the type of metric you need. The metric tensor, or metric, is a set of values that can be used to calculate the four-dimensional intervals that exist between event points. This set of quantities fully characterizes both the gravitational field and the space-time geometry. Geometrically traversable wormholes in space are even simpler than black holes. They do not have horizons that lead to cataclysms with the passage of time. At different points, time can go at a different pace, but it should not stop or speed up indefinitely.
Pulsars: The Beacon Factor
In essence, a pulsar is a rapidly rotating neutron star. A neutron star is the highly compacted core of a dead star left over from a supernova explosion. This neutron star has a powerful magnetic field. This magnetic field is about one trillion times stronger than the Earth's magnetic field. The magnetic field causes a neutron star to emit strong radio waves and radioactive particles from its north and south poles. These particles can include various radiations, including visible light.
Pulsars that emit powerful gamma rays are known as gamma ray pulsars. If a neutron star is located with its pole towards the Earth, then we can see radio waves every time as soon as one of the poles falls into our foreshortening. This effect is very similar to the lighthouse effect. To a stationary observer, it seems that the light of a rotating beacon is constantly blinking, then disappearing, then appearing again. In the same way, a pulsar appears to blink as it rotates its poles relative to the Earth. Different pulsars fire at different speeds, depending on the size and mass of the neutron star. Sometimes a pulsar can have a companion. In some cases, he can attract his companion, which makes him rotate even faster. The fastest pulsars can emit more than a hundred pulses per second.
A hypothetical "wormhole", which is also called a "wormhole" or "wormhole" (literal translation of wormhole) is a kind of space-time tunnel that allows an object to move from point A to point B in the Universe not in a straight line, but around space. If it's easier, then take any piece of paper, fold it in half and pierce it, the resulting hole will be the same wormhole. So there is a theory that the space in the Universe can be conditionally the same sheet of paper, only adjusted for the third dimension. Various scientists deduce hypotheses that thanks to wormholes travel in space-time is possible. But at the same time, no one knows exactly what dangers wormholes can pose and what can actually be on the other side of them.
Wormhole theory
In 1935, physicists Albert Einstein and Nathan Rosen, using the theory of general relativity, suggested that there are special "bridges" across space-time in the universe. These paths, called Einstein-Rosen bridges (or wormholes), connect two completely different points in spacetime by theoretically creating a warp in space that shortens travel from one point to another.
Again, hypothetically, any wormhole consists of two entrances and a neck (that is, the same tunnel). In this case, most likely, the entrances at the wormhole are spheroidal in shape, and the neck can represent both a straight segment of space and a spiral one.
The general theory of relativity mathematically proves the probability of the existence of wormholes, but so far none of them have been discovered by man. The difficulty in detecting it lies in the fact that the alleged huge mass of wormholes and gravitational effects simply absorb light and prevent it from being reflected.
Several hypotheses based on general relativity suggest the existence of wormholes, where black holes play the roles of entry and exit. But it is worth considering that the appearance of the black holes themselves, formed from the explosion of dying stars, in no way creates a wormhole.
Journey through a wormhole
In science fiction, it's not uncommon for protagonists to travel through wormholes. But in reality, such a journey is far from being as simple as it is shown in films and told in fantasy literature.
The first problem that will stand in the way of the possibility of such travel is the size of wormholes. It is believed that the very first wormholes were very small in size, on the order of 10-33 centimeters, but due to the expansion of the Universe, it became possible that the wormholes themselves expanded and increased along with it. Another problem with wormholes is their stability. Or rather, instability.
Wormholes explained by the Einstein-Rosen theory will be useless for space-time travel because they collapse (close) very quickly. But more recent studies of these issues imply the presence of "exotic matter" that allows burrows to maintain their structure for a longer period of time.
Not to be confused with black matter and antimatter, this exotic matter is composed of negative density energy and colossal negative pressure. The mention of such matter is present only in some theories of vacuum within the framework of quantum field theory.
Yet theoretical science believes that if wormholes contain enough of this exotic energy, either naturally occurring or artificially generated, then it will be possible to transmit information or even objects through space-time.
The same hypotheses suggest that wormholes can connect not only two points within one universe, but also be the entrance to others. Some scientists believe that if one wormhole entrance is moved in a certain way, then time travel will be possible. But, for example, the famous British cosmologist Stephen Hawking believes that such use of wormholes is impossible.
Nevertheless, some scientific minds insist that if stabilization of wormholes by exotic matter is indeed possible, then it will be possible for people to safely travel through such wormholes. And due to the "ordinary" matter, if desired and necessary, such portals can be destabilized back.
Unfortunately, today's technologies of mankind are not enough for wormholes to be artificially enlarged and stabilized, in case they are nevertheless discovered. But scientists continue to explore the concepts and methods for fast space travel, and maybe one day science will come up with the right solution.
Video Wormhole: door through the looking glass
Sci-fi fans hope that humanity will one day be able to travel to the far reaches of the universe through a wormhole.
A wormhole is a theoretical tunnel through space-time that will potentially allow faster travel between distant points in space - from one galaxy to another, for example, as was shown in Christopher Nolan's film "Interstellar", which was released in theaters around the world at the beginning of this month.
While wormholes are possible according to Einstein's theory of general relativity, such exotic travels are likely to remain in the realm of science fiction, said renowned astrophysicist Kip Thorne of the California Institute of Technology in Pasadena, who served as an advisor and executive producer on Interstellar. .
"The point is, we just don't know anything about them," said Thorne, who is one of the world's leading experts on relativity, black holes and wormholes. "But there are very strong indications that a person, according to the laws of physics, will not be able to travel through them."
"The main reason has to do with the instability of wormholes," he added. "The walls of the wormholes are collapsing so fast that nothing can get through them."
Keeping the wormholes open will require the use of something anti-gravity, namely negative energy. Negative energy was created in the laboratory using quantum effects: one region of space receives the energy of another region, in which a deficiency forms.
"So it's theoretically possible," he said. "But we can never get enough negative energy, which will be able to keep the walls of the wormhole open."
Also, wormholes (if they exist at all) almost certainly cannot form naturally. That is, they must be created with the help of an advanced civilization.
That's exactly what happened in "Interstellar": Mysterious creatures built a wormhole near Saturn, allowing a small group of pioneers, led by former farmer Cooper (played by Matthew McConaughey), to set out in search of a new home for humanity to exist on Earth. threatened by a global crop failure.
Those interested in learning more about the science in Interstellar, which deals with gravitational slowdown and depicts several alien planets orbiting a closely spaced one, should read Thorne's new book, which is unequivocally titled The Science of Interstellar.
Where is the wormhole. Wormholes in general relativity
(GR) allows the existence of such tunnels, although for the existence of a traversable wormhole it is necessary that it be filled with a negative one, which creates a strong gravitational repulsion and prevents the hole from collapsing. Wormhole-type solutions arise in various options, although up to full study question is still very far away.
The area near the narrowest section of the molehill is called the "throat". Wormholes are divided into "intra-universe" and "inter-universe", depending on whether it is possible to connect its inputs with a curve that does not cross the neck.
There are also passable (traversable) and impassable molehills. The latter include those tunnels that are too fast for an observer or a signal (having a speed of no more than light speed) to get from one entrance to another. A classic example of an impassable molehill is in, but a passable one is.
A traversable intraworld wormhole provides a hypothetical possibility if, for example, one of its entrances is moving relative to the other, or if it is in a strong one where the passage of time slows down. Also, wormholes can hypothetically create an opportunity for interstellar travel, and as such, wormholes are often found in.
Space wormholes. Through the "molehills" - to the stars?
Unfortunately, about practical use"wormholes" to reach remote space objects are not yet discussed. Their properties, varieties, places of possible location are still known only theoretically - although, you see, this is already quite a lot. After all, we have many examples of how the theoretical constructions that seemed purely speculative led to the emergence of new technologies that radically changed the life of mankind. Nuclear power, computers, mobile connection, genetic engineering ... but you never know what else?
In the meantime, the following is known about "wormholes", or "wormholes". In 1935, Albert Einstein and the American-Israeli physicist Nathan Rosen suggested the existence of a kind of tunnels connecting various remote regions of space. At that time, they were not yet called "wormholes", or "mole holes", but simply - "Einstein-Rosen bridges". Since such bridges required a very strong curvature of space for the emergence of such bridges, the time of their existence was very short. No one and nothing would have time to "run" over such a bridge - under the influence of gravity, it almost immediately "collapsed".
And therefore, it remained completely useless in a practical sense, although an amusing consequence of the general theory of relativity.
However, later ideas appeared that some interdimensional tunnels could exist for quite a long time - provided that they are filled with some exotic matter with a negative energy density. Such matter will create gravitational repulsion instead of attraction and thus prevent the channel from “collapsing”. Then the name "wormhole" appeared. By the way, our scientists prefer the name "molehill" or "wormhole": the meaning is the same, but it sounds much nicer ...
American physicist John Archibald Wheeler (1911-2008), developing the theory of "wormholes", suggested that they are penetrated electric field; moreover, the electric charges themselves are, in fact, the mouths of microscopic "wormholes". Russian astrophysicist Academician Nikolai Semyonovich Kardashev believes that "wormholes" can reach giant size and that in the center of our Galaxy there are not massive black holes at all, but the mouths of such "burrows".
Of practical interest to future space travelers will be "wormholes", which are kept in a stable state for quite a long time and, moreover, are suitable for spacecraft to pass through them.
Americans Kip Thorne and Michael Morris created a theoretical model of such channels. However, their stability is ensured by “exotic matter”, about which nothing is really known and which, perhaps, it is better for earthly technology not to even meddle.
But Russian theorists Sergei Krasnikov from the Pulkovo Observatory and Sergei Sushkov from Kazan Federal University put forward the idea that the stability of a wormhole can be achieved without any negative energy density, but simply due to the polarization of the vacuum in the “hole” (the so-called Sushkov mechanism) .
In general, now there is a whole set of theories of "wormholes" (or, if you like, "wormholes"). A very general and speculative classification divides them into "passable" - stable, Morris - Thorn wormholes, and impassable - Einstein - Rosen bridges. In addition, wormholes vary in scale - from microscopic to gigantic, comparable in size to galactic "black holes". And finally, according to their purpose: "intra-universe", connecting different places of the same curved Universe, and "inter-universe" (inter-universe), allowing you to get into another space-time continuum.
