Everything that exists in the universe. How many universes are in our universe? Parallel universes: hypotheses require confirmation

What is outside the universe? This question is too complex for human understanding. This is due to the fact that in the very first place it is necessary to determine its boundaries, and this is far from simple.

The generally accepted answer takes into account only the observable universe. According to him, the dimensions are determined by the speed of light, because it is possible to see only the light that objects in space emit or reflect. It is impossible to look further than the most distant light that travels all the time of the existence of the universe.

The space continues to increase, but is still finite. Its size is sometimes referred to as the Hubble volume or sphere. Man in the universe will probably never be able to know what is beyond its boundaries. So for all research, this is the only space that you will ever have to interact with. At least in the near future.

Greatness

Everyone knows that the universe is big. How many million light years does it span?

Astronomers carefully study the cosmic radiation of the microwave background - the afterglow of the Big Bang. They are looking for a connection between what is happening on one side of the sky and what is on the other. And while there is no evidence that there is something in common. This means that for 13.8 billion years in any direction the Universe does not repeat itself. This is how long it takes for light to reach at least the visible edge of this space.

We are still concerned with the question of what is beyond the observable universe. Astronomers admit that the cosmos is infinite. "Matter" in it (energy, galaxies, etc.) is distributed in exactly the same way as in the observable Universe. If this is true, then there are various anomalies of what is on the edge.

There are not just more different planets outside the Hubble volume. There you can find everything that can possibly exist. If you get far enough, you might even find another solar system with an Earth identical in every way except that you had porridge for breakfast instead of scrambled eggs. Or there was no breakfast at all. Or let's say you got up early and robbed a bank.

In fact, cosmologists believe that if you go far enough, you can find another Hubble sphere that is completely identical to ours. Most scientists believe that the universe as we know it has boundaries. What is beyond them remains the greatest mystery.

Cosmological principle

This concept means that regardless of the place and direction of the observer, everyone sees the same picture of the Universe. Of course, this does not apply to smaller scale studies. Such homogeneity of space is caused by the equality of all its points. This phenomenon can only be detected on the scale of a cluster of galaxies.

Something akin to this concept was first proposed by Sir Isaac Newton in 1687. And later, in the 20th century, the same was confirmed by the observations of other scientists. Logically, if everything originated from a single point in the Big Bang and then expanded into the universe, it would remain fairly uniform.

The distance at which the cosmological principle can be observed to find this apparent uniform distribution of matter is approximately 300 million light-years from Earth.

However, everything changed in 1973. Then an anomaly was discovered that violates the cosmological principle.

Great attractor

A huge concentration of mass was found at a distance of 250 million light years, near the constellations of Hydra and Centaurus. Its weight is so great that it could be compared with tens of thousands of masses of the Milky Ways. This anomaly is considered a galactic supercluster.

This object is called the Great Attractor. Its gravitational force is so strong that it affects other galaxies and their clusters for several hundred light-years. He long time remained one of the biggest mysteries of the cosmos.

In 1990, it was discovered that the movement of colossal clusters of galaxies, called the Great Attractor, tends to another region of space - beyond the edge of the Universe. So far, this process can be observed, although the anomaly itself is in the “zone of avoidance”.

dark energy

According to Hubble's Law, all galaxies should move uniformly apart from each other, preserving the cosmological principle. However, in 2008 a new discovery appeared.

The Wilkinson Microwave Anisotropy Probe (WMAP) found a large group of clusters moving in the same direction at speeds up to 600 miles per second. All of them were on their way to a small area of ​​the sky between the constellations Centaurus and Parus.

There is no obvious reason for this, and since it was inexplicable phenomenon, it was called "dark energy". It is caused by something outside the observable universe. At present, there is only speculation about its nature.

If clusters of galaxies are drawn towards a colossal black hole, then their movement should be accelerating. Dark energy indicates a constant speed of cosmic bodies in billions of light years.

One of possible causes this process - massive structures that are outside the universe. They have a huge gravitational effect. Within the observable universe, there are no giant structures with enough gravitational gravity to cause this phenomenon. But this does not mean that they could not exist outside the observable area.

This would mean that the structure of the universe is not uniform. As for the structures themselves, they can be literally anything, from aggregates of matter to energy on a scale that can hardly be imagined. It is even possible that these are guiding gravitational forces from other Universes.

Endless Bubbles

Talking about something outside of the Hubble sphere is not entirely correct, since it still has the identical structure of the Metagalaxy. "Unknown" has the same physical laws of the Universe and constants. There is a version that the Big Bang caused the appearance of bubbles in the structure of space.

Immediately after it, before the inflation of the Universe began, a kind of "cosmic foam" arose, existing as a cluster of "bubbles". One of the objects of this substance suddenly expanded, eventually becoming the universe known today.

But what came out of the other bubbles? Alexander Kashlinsky, head of the NASA team, the organization that discovered "dark energy," said: "If you move far enough away, you can see a structure that is outside the bubble, outside the universe. These structures should cause movement.”

Thus, "dark energy" is perceived as the first evidence of the existence of another Universe, or even a "Multiverse".

Each bubble is an area that has stopped expanding along with the rest of the space. She formed her own universe with her own special laws.

In this scenario, the space is infinite and each bubble also has no boundaries. Even if it is possible to breach the boundary of one of them, the space between them is still expanding. Over time, it will be impossible to reach the next bubble. Such a phenomenon is still one of the greatest mysteries of the cosmos.

Black hole

The theory proposed by the physicist Lee Smolin assumes that each similar space object in the structure of the Metagalaxy causes the formation of a new one. One has only to imagine how many black holes there are in the universe. Inside each, there are physical laws that are different from those of the predecessor. A similar hypothesis was first stated in 1992 in the book "The Life of the Cosmos".

Stars around the world that fall into black holes are compressed to incredibly extreme densities. Under such conditions, this space explodes and expands into a new universe of its own, different from the original. The point where time stops inside the black hole is the beginning of the Big Bang of the new Metagalaxy.

Extreme conditions inside the destroyed black hole lead to small random changes in the basic physical forces and parameters in the daughter Universe. Each of them has different characteristics and indicators from the parent.

The existence of stars is a prerequisite for the formation of life. This is due to the fact that carbon and other complex molecules that provide life are created in them. Therefore, the same conditions are needed for the formation of beings and the Universe.

A criticism of cosmic natural selection as a scientific hypothesis is the lack of direct evidence for this stage. But it should be borne in mind that, in terms of beliefs, it is no worse than the proposed scientific alternatives. There is no evidence of what is outside the universe, be it the Multiverse, string theory, or cyclic space.

Many parallel universes

This idea seems to be something that has little to do with modern theoretical physics. But the idea of ​​the existence of the Multiverse has long been considered a scientific possibility, although it still causes active discussion and destructive debate among physicists. This option completely destroys the idea of ​​how many universes there are in space.

It is important to keep in mind that the Multiverse is not a theory, but rather a consequence of the current understanding of theoretical physics. This distinction is of decisive importance. No one waved his hand and said: "Let there be a Multiverse!". This idea was derived from current teachings such as quantum mechanics and string theory.

Multiverse and quantum physics

Many people know the thought experiment "Schrödinger's Cat". Its essence lies in the fact that Erwin Schrödinger, an Austrian theoretical physicist, pointed out the imperfection of quantum mechanics.

The scientist proposes to imagine an animal that was placed in a closed box. If you open it, you can find out one of two states of the cat. But as long as the box is closed, the animal is either alive or dead. This proves that there is no state that combines life and death.

All this seems impossible simply because human perception cannot comprehend it.

But it is quite real according to the strange rules of quantum mechanics. The space of all possibilities in it is huge. Mathematically, a quantum mechanical state is the sum (or superposition) of all possible states. In the case of "Schrödinger's Cat", the experiment is a superposition of "dead" and "alive" positions.

But how is this to be interpreted so that it makes any practical sense? A popular way is to think of all these possibilities in such a way that the only "objectively true" state of the cat is observed. However, one can also agree that these possibilities are true and that they all exist in different Universes.

String theory

This is the most promising opportunity to combine quantum mechanics and gravity. This is difficult because gravity is just as indescribable on a small scale as atoms and subatomic particles are in quantum mechanics.

But string theory, which says that all fundamental particles are made up of monomeric elements, describes all the known forces of nature at once. These include gravity, electromagnetism and nuclear forces.

However, for mathematical theory strings require at least ten physical dimensions. We can observe only four dimensions: height, width, depth and time. Therefore, additional dimensions are hidden from us.

In order to be able to use theory to explain physical phenomena, these additional studies are "densified" and too small on a small scale.

The problem or peculiarity of string theory is that there are many ways to perform a compactification. Each of these results in the creation of a universe with different physical laws, such as different electron masses and gravity constants. However, there are also serious objections to the compactification methodology. Therefore, the problem is not completely solved.

But the obvious question is: which of these possibilities are we living in? String theory does not provide a mechanism for determining this. It makes it useless because it is not possible to thoroughly test it. But exploring the edge of the universe turned that error into a feature.

Consequences of the Big Bang

During the earliest universe, there was a period of accelerated expansion called inflation. She originally explained why the Hubble sphere is nearly uniform in temperature. However, inflation also predicted a spectrum of temperature fluctuations around this equilibrium, which was later confirmed by several spacecraft.

Although the exact details of the theory are still hotly debated, inflation is widely accepted by physicists. However, the implication of this theory is that there must be other objects in the universe that are still accelerating. Due to the quantum fluctuations of space-time, some parts of it will never reach the final state. This means that space will expand forever.

This mechanism generates an infinite number of universes. Combining this scenario with string theory, there is a possibility that each of them has a different compactification of extra dimensions and therefore has different physical laws of the universe.

According to the teachings of the Multiverse, predicted by string theory and inflation, all universes live in the same physical space and can overlap. They must inevitably collide, leaving traces in the cosmic sky. Their character has a wide range - from cold or hot spots on the cosmic microwave background to anomalous voids in the distribution of galaxies.

Since collision with other universes must occur in a certain direction, any interference is expected to break the homogeneity.

Some scientists look for them through anomalies in the cosmic microwave background, the afterglow of the Big Bang. Others are in gravitational waves that ripple through space-time as massive objects pass. These waves can directly prove the existence of inflation, which ultimately strengthens support for the Multiverse theory.

Doctor of Pedagogical Sciences E. LEVITAN.

Gaze into previously unattainable depths of the universe.

An inquisitive pilgrim has reached the "end of the world" and is trying to see: what is there, beyond the edge?

Illustration for the hypothesis of the birth of metagalaxies from a decaying giant bubble. The bubble grew to a huge size at the stage of rapid "inflation" of the Universe. (Drawing from the magazine "Earth and Universe".)

Isn't it a strange title for an article? Isn't the universe alone? By the end of the 20th century, it became clear that the picture of the universe is immeasurably more complicated than the one that seemed completely obvious a hundred years ago. Neither the Earth, nor the Sun, nor our Galaxy turned out to be the center of the Universe. The geocentric, heliocentric and galactocentric systems of the world have been replaced by the idea that we live in an expanding Metagalaxy (our Universe). It contains countless galaxies. Each, like ours, consists of tens or even hundreds of billions of sun-stars. And there is no center. It only seems to the inhabitants of each of the galaxies that it is from them that other star islands scatter in all directions. A few decades ago, astronomers could only speculate that planetary systems like our solar system existed somewhere. Now - with a high degree of certainty, they name a number of stars in which "protoplanetary disks" have been discovered (planets will someday form from them), and they confidently talk about the discovery of several planetary systems.

The process of knowing the Universe is endless. And the farther, the more and more daring, sometimes seeming absolutely fantastic, tasks are set by the researchers. So why not assume that astronomers will someday discover other universes? After all, it is quite probable that our Metagalaxy is not the whole Universe, but only some part of it...

It is unlikely that modern astronomers and even astronomers of the very distant future will ever be able to see other universes with their own eyes. Nevertheless, science already now has some data that our Metagalaxy may turn out to be one of many mini-universes.

Hardly anyone doubts that life and intelligence can arise, exist and develop only at a certain stage in the evolution of the Universe. It is hard to imagine that any forms of life appeared before the stars and the planets moving around them. And not every planet, as we know, is suitable for life. Certain conditions are necessary: ​​a rather narrow temperature range, the composition of the air suitable for breathing, water... In the solar system, the Earth turned out to be in such a "belt of life". And our Sun is probably located in the "life belt" of the Galaxy (at a certain distance from its center).

Many extremely faint (in brightness) and distant galaxies have been photographed in this way. The most striking of them managed to consider some details: structure, structural features. The brightness of the faintest of the galaxies obtained in the picture is 27.5 m, and point objects (stars) are even fainter (up to 28.1 m)! Recall that with the naked eye, people with good eyesight and under the most favorable observation conditions see stars of about 6 m (this is 250 million times brighter objects than those with a brightness of 27 m).
Similar ground-based telescopes currently being created are already comparable in their capabilities to the capabilities of the Hubble Space Telescope, and in some ways even surpass them.
What conditions are needed for the formation of stars and planets? First of all, this is due to such fundamental physical constants as the gravitational constant and the constants of other physical interactions (weak, electromagnetic and strong). The numerical values ​​of these constants are well known to physicists. Even schoolchildren, studying the law of universal gravitation, get acquainted with the constant (constant) of gravitation. Students from the general physics course will also learn about the constants of three other types of physical interaction.

More recently, astrophysicists and cosmologists have realized that it is the existing values ​​of the constants of physical interactions that are necessary for the Universe to be as it is. With other physical constants, the Universe would be completely different. For example, the lifetime of the Sun could be only 50 million years (this is too short for the emergence and development of life on the planets). Or, say, if the Universe consisted only of hydrogen or only of helium - this would also make it completely lifeless. Variants of the Universe with other masses of protons, neutrons, electrons are in no way suitable for life in the form in which we know it. Calculations convince: we need elementary particles exactly as they are! And the dimension of space is of fundamental importance for the existence of both planetary systems and individual atoms (with electrons moving around nuclei). We live in a three-dimensional world and could not live in a world with more or less dimensions.

It turns out that everything in the Universe seems to be “tailored” so that life could appear and develop in it! Of course, we have drawn a very simplified picture, because not only physics, but also chemistry and biology play a huge role in the emergence and development of life. However, with a different physics, both chemistry and biology could become different ...

All these considerations lead to what in philosophy is called the anthropic principle. This is an attempt to consider the Universe in a "man-dimensional" dimension, that is, from the point of view of its existence. By itself, the anthropic principle cannot explain why the universe is the way we observe it. But to some extent, it helps researchers formulate new problems. For example, the amazing "fitting" of the fundamental properties of our universe can be seen as evidence of the uniqueness of our universe. And from here, it seems, one step to the hypothesis of the existence of completely different universes, worlds that are absolutely not similar to ours. And their number, in principle, can be unlimitedly huge.

Now let's try to approach the problem of the existence of other universes from the standpoint of modern cosmology, a science that studies the Universe as a whole (as opposed to cosmogony, which studies the origin of planets, stars, galaxies).

Remember, the discovery that the Metagalaxy is expanding almost immediately led to the Big Bang hypothesis (see "Science and Life" No. 2, 1998). It is believed to have occurred about 15 billion years ago. Very dense and hot matter passed one after another stage of the "hot Universe". So, 1 billion years after the Big Bang, "proto-galaxies" began to appear from the clouds of hydrogen and helium that had formed by that time, and in them - the first stars. The "hot universe" hypothesis is based on calculations that allow us to trace the history of the early universe from literally the first second.

Here is what our well-known physicist Academician Ya. around the Sun. Both theories occupied a central place in the picture of the universe of their time, and both had many opponents who argued that the new ideas embedded in them were absurd and contrary to common sense. But such statements are not able to prevent the success of new theories. "

This was said in the early 80s, when the first attempts were already being made to significantly supplement the "hot universe" hypothesis with an important idea about what happened in the first second of "creation" when the temperature was above 10 28 K. Take one more step towards " the very beginning" was possible thanks to the latest achievements of elementary particle physics. It was at the intersection of physics and astrophysics that the "inflating Universe" hypothesis began to develop (see "Science and Life" No. 8, 1985). Due to its unusual nature, the "inflating Universe" hypothesis can be quite classified among the most "crazy". However, it is known from the history of science that it is precisely such hypotheses and theories that often become important milestones in the development of science.

The essence of the "inflating Universe" hypothesis is that in the "very beginning" the Universe expanded monstrously rapidly. For some 10 -32 s, the size of the emerging Universe has grown not by 10 times, as it would be expected with a "normal" expansion, but by 10 50 or even 10 1000000 times. The expansion was accelerated, and the energy per unit volume remained unchanged. Scientists prove that the initial moments of the expansion occurred in a "vacuum". The word is put here in quotation marks, since the vacuum was not ordinary, but false, because it is difficult to call ordinary "vacuum" with a density of 10 77 kg / m 3! From such a false (or physical) vacuum, which had amazing properties (for example, negative pressure), not one, but many metagalaxies (including, of course, ours) could form. And each of them is a mini-universe with its own set of physical constants, its own structure and other features inherent in it (for more details, see "Earth and the Universe" No. 1, 1989).

But where are these "relatives" of our Metagalaxy? In all likelihood, they, like our Universe, were formed as a result of "inflating" domains ("domains" from the French domaine - area, sphere), into which the very early Universe immediately broke up. Since each such region has swelled up to a size exceeding the current size of the Metagalaxy, their boundaries are separated from one another by great distances. Perhaps the nearest mini-universe is about 10 35 light-years away. Recall that the size of the Metagalaxy is "only" 10 10 light years! It turns out that not next to us, but somewhere very, very far from each other, there are other, probably completely outlandish, according to our concepts, worlds ...

So it is possible that the world we live in is much more complex than hitherto thought. It is likely that it consists of countless universes in the universe. About this Big Universe, complex, surprisingly diverse, we still know practically nothing. But we still seem to know one thing. Whatever other mini-worlds far from us, each of them is real. They are not fictional, like some now fashionable "parallel" worlds, which people who are far from science often talk about now.

Well, what does it all come down to in the end? Stars, planets, galaxies, metagalaxies all together occupy only the tiniest place in the boundless expanses of extremely rarefied matter... Is there nothing else in the Universe? It's too simple... It's somehow even hard to believe.

And astrophysicists have long been looking for something in the universe. Observations testify to the existence of a "hidden mass", some kind of invisible "dark" matter. It cannot be seen even in the most powerful telescope, but it manifests itself by its gravitational effect on ordinary matter. Until quite recently, astrophysicists assumed that there is about the same amount of such hidden matter in galaxies and in the space between them as there is observable matter. Recently, however, many researchers have come to an even more sensational conclusion: "normal" matter in our universe - no more than five percent, the rest - "invisible".

It is assumed that 70 percent of them are quantum mechanical, vacuum structures evenly distributed in space (it is they that determine the expansion of the Metagalaxy), and 25 percent are various exotic objects. For example, black holes of low mass, almost point-like; very extended objects - "strings"; domain walls, which we have already mentioned. But in addition to such objects, the "hidden" mass can be composed of entire classes of hypothetical elementary particles, for example, "mirror particles". The well-known Russian astrophysicist, Academician of the Russian Academy of Sciences N. S. Kardashev (once upon a time we were both active members of the astronomical circle at the Moscow Planetarium) suggests that the “mirror world” invisible to us with its planets and stars can consist of “mirror particles” . And there are about five times more substances in the "mirror world" than in ours. It turns out that scientists have some reason to believe that the "mirror world" seems to permeate ours. Just can't find it yet.

The idea is almost fabulous, fantastic. But who knows, maybe one of you - the current lovers of astronomy - will become a researcher in the coming XXI century and will be able to reveal the secret of the "mirror universe".

Related publications in "Science and Life"

Shulga V. Cosmic lenses and the search for dark matter in the Universe. - 1994, No. 2.

Roizen I. Universe between moment and eternity. - 1996, Nos. 11, 12.

Sazhin M., Shulga V. Riddles of cosmic strings. - 1998, No. 4.

American scientist and famous popularizer of science Kaku Michio wrote a book in which he argues with common sense. For normal person the three-dimensional world is the norm, to which Einstein, not without difficulty, added the fourth dimension - time. But modern physics has been working for quite a long time on the theory of hyperspace, according to which the Universe consists not only of time and space, but also of something else - the fifth dimension, the sixth dimension ... The human mind is now unable to imagine such a thing, but it is accessible to the language of mathematics.

Large mathematical calculations within the framework of the theory of hyperspace proved that if we assume the theoretical existence of other dimensions, then seemingly unsolvable problems of physics are easily solved: for example, the answer to the question of the possible interaction of light and gravity. Moreover, the discovery of new dimensions will make it possible to merge together still scattered knowledge about the structure of the Universe, thanks to which the "theory of everything" sought from ancient times may appear. And in order for people to prepare for its appearance, Michio translated the theory of hyperspace from the language of formulas for people living in a three-dimensional world.

Russian Planet, with the permission of the Alpina Non-Fiction publishing house, publishes a fragment of Kaku Michio's book Hyperspace: A Scientific Odyssey Through Parallel Worlds, Holes in Time, and the Tenth Dimension, dedicated to the possibility of the existence of several universes.

In 1957, the physicist Hugh Everett suggested that the universe constantly "forks" in the process of evolution, like a road at a fork. In one universe, the uranium atom does not decay, and the cat remains alive. In another, the uranium atom decays and the cat dies. If Everett is right, there are an infinite number of universes. Each universe is connected to the others by a network of "forks in the road." Or, as the Argentinian Jorge Luis Borges wrote in The Garden of Forking Paths, “Eternally branching, time leads to innumerable futures.”

Physicist Bryce DeWitt, one of the proponents of the many-world theory, described the lasting impression it made on him: “Each quantum transition that occurs in every star, in every galaxy, and in every remote corner of the universe, splits our local world on Earth into myriad copies of itself. . I still distinctly remember the shock I felt when I first encountered this concept of many worlds. According to the postulate of the many-world theory, all possible quantum worlds exist. On some worlds, like the dominant form of life on Earth, human beings live. In others, events in the subatomic realm prevented the emergence of man.

Physicist Frank Wilczek wrote:

“They say that the history of the world would have turned out completely differently if Helen of Troy had a wart on her nose. So, warts arise due to a single cell mutation, often caused by the ultraviolet rays of the sun. Conclusion: there are many worlds in which Helen of Troy really had a wart on her nose.

In fact, the idea of ​​multiple universes is old. Saint and philosopher Albert Magnus wrote: “Are there really many worlds, or is there only one world? This is one of the noblest and most exciting questions in the study of Nature." However, the ancient idea is given a modern twist: the numerous worlds solve the paradox of Schrödinger's cat. In one universe a cat may be dead, in another it may be alive.

As strange as Everett's many-worlds theory may seem, it can be shown to be mathematically equivalent to the usual interpretation of quantum theory. But it so happened that the many-world theory is not popular among physicists. It is impossible to reject it, but the very idea of ​​an infinite number of equally real universes, each of which is divided into two every minute, is a philosophical nightmare for physicists who love simplicity. In physics, the so-called Occam principle applies, according to which the simplest path should always be chosen, ignoring complicated alternatives, especially if they are not measurable.

(Thus, Occam's principle rejects the ancient theory of the ether, according to which the entire universe was once filled with a mysterious gas. The ether theory provided a convenient answer to the tricky question: if light is a wave and if light can propagate in a vacuum, then what are wavelike oscillations? The answer was that the ether, like a liquid, oscillates even in a vacuum. Einstein proved that the ether is not necessary. However, he never claimed that the ether does not exist - he simply said that it is irrelevant. Thus, following Occam's principle, physicists no longer turn to ether.)

It can be shown that communication between the many worlds of Everett is impossible. Therefore, each universe is unaware of the existence of the others. If experiments cannot confirm the existence of these worlds, we should, in accordance with Occam's principle, exclude them.

Continuing in the same vein, physicists refrain from making categorical statements that angels and miracles do not exist. Perhaps there are both. But miracles, almost by definition, do not occur regularly, and therefore cannot be quantified experimentally. So, in accordance with Occam's principle, they should be ignored (unless, of course, we find a reproducible and measurable miracle or an angel). One of the authors of the many-world theory, Everett's mentor John Wheeler reluctantly rejected both, as "it is too heavy to carry such bulky metaphysical baggage."

However, the situation with the unpopularity of the many-world theory can be corrected by a gradual increase in the popularity of the Hawking wave function in relation to the Universe. Everett's theory is based on single particles and the impossibility of communication between universes after their separation. Hawking's theory, although related to the above, nevertheless goes further: it is based on an infinite number of self-consistent universes (and not just particles), and the theory itself postulates the possibility of tunneling between them (through "wormholes").

Hawking even found a solution to the wave function of the universe. He is convinced of the correctness of his approach partly because the theory is well defined (if, as already mentioned, the theory is finally defined in ten dimensions). Its purpose is to show that the wave function of the universe takes big values near a universe similar to ours. So our universe is almost certainly a universe, but definitely not the only one.

To date, a number of international conferences devoted to the wave function of the Universe have been held. But, as before, from a mathematical point of view, the wave function of the universe is beyond the computational abilities of people living on our planet, and we may have to wait many years before any enthusiast finds an exact solution to Hawking's equations.

Parallel Worlds

The main difference between Everett's many-world theory and Hawking's wave function for the universe lies in Hawking's central idea of ​​"wormholes" connecting parallel universes. However, do not imagine that one day you will go home from work, open the door, enter a parallel universe and find that your loved ones have never heard of you. Instead of rushing to meet you after a hard day, your family will show up in a panic, yell that there is a stranger in the house, and you will be arrested for trespassing. Such scenarios are possible only in the cinema. According to Hawking, "wormholes" constantly connect our universe with billions of billions of parallel universes, but on average, the size of these "wormholes" is extremely small and comparable to the Planck length (about 100 billion billion times smaller than a proton, that is, too small for a person to move). Moreover, since large quantum transitions between universes are rare, it is possible that such an event will have to wait a very long time - longer than the universe exists.

Hugh Everett. Photo: physicsmasterclasses.org

Thus, in full accordance with the laws of physics (although extremely unlikely), someone could fall into a parallel universe, twin to ours, which looks exactly like ours, with the exception of one small but important difference that arose at some point in time when these universes have been divided.

O parallel worlds this type was written by John Wyndham in the story "Search at random" (Random Quest). British nuclear physicist Colin Trafford almost died in 1954 due to an accident during an experiment. Instead of being taken to the hospital, he finds himself safe and sound in a remote area of ​​London. Trafford is glad that he got off so lightly, but soon realizes that something has happened. The headlines in the newspapers are incredible. The Second World War never happened. There is no mention of any atomic bomb.

World history is different. What's more, after accidentally looking at a shelf in a store, Trafford notices his own name and photograph and discovers that he is a best-selling author. He is shocked. His exact copy exists in this world, in addition, he is not a physicist, but a writer!

Is he dreaming? Many years ago, he thought about becoming a writer, but became a physicist. Apparently, a different path was chosen in this parallel universe.

Trafford flips through the London telephone directory and finds his name on the list, but the address in it is unfamiliar to him. Amazed, Trafford decides to visit "at home".

In "his" apartment, he is amazed to meet "his" wife, whom he had never seen before - beautiful woman, outraged by "his" numerous novels with other women. She reproaches him for cheating, but notices that her husband is puzzled by something. Trafford discovers that his doppelganger is a villain and a libertine, and realizes that he cannot fight back a beautiful stranger, although she considers herself his wife. Apparently, he and his doppelgänger have swapped universes.

Trafford gradually falls in love with his "own" wife. And he does not understand how his double can treat this lovely woman so dismissively. The next few weeks spent together are the best of their lives. Trafford decides to make amends for all the wrongs that his doppelgänger has inflicted on his wife over the years. But when the spouses seem to recognize each other again, Trafford suddenly finds himself thrown back into his universe and separated from his beloved. In the familiar universe, he undertakes a desperate search for "his wife." And he learns that people living in his universe have counterparts in another - not all, but most. Trafford comes to the conclusion that his "wife" must have a double somewhere in this world.

Like a man possessed, he grabs at any clue, tries to remember everything he knows about twin universes. arm having knowledge in the field of history and physics, he concludes that the two worlds diverged in their development due to some turning point in 1926 or 1927 du . Trafford believes that a single event could separate the universes.

Then he begins to meticulously investigate the history of several families. He spends all his savings, interviews dozens of people, and finally finds "his wife's" family. He eventually discovers the same woman in his universe and marries her.

Part of the deep space image "Hubble Ultra Deep Field". All you see are galaxies.

More recently, in the 1920s, the famous astronomer Edwin Hubble was able to prove that ours is not the only existing galaxy. Today we are already accustomed to the fact that space is filled with thousands and millions of other galaxies, against which ours looks very tiny. But exactly how many galaxies in the Universe are next to us? Today we will find the answer to this question.

It sounds incredible, but even our great-grandfathers, even the most scientists, considered our Milky Way a metagalaxy - an object covering the entire Universe. Their delusion was quite logically explained by the imperfection of the telescopes of that time - even the best of them saw galaxies as blurry spots, which is why they were called nebulae without exception. It was believed that stars and planets were formed from them over time, as ours was once formed. solar system. This conjecture was confirmed by the discovery of the first planetary nebula in 1796, in the center of which was a star. Therefore, scientists believed that all other nebulous objects in the sky are the same clouds of dust and gas, in which stars have not yet had time to form.

The first steps

Naturally, progress did not stand still. Already in 1845, William Parsons built the Leviathan telescope, gigantic for those times, the size of which was close to two meters. Wishing to prove that "nebulae" are actually made of stars, he seriously brought astronomy closer to modern concept galaxies. For the first time, he was able to notice the spiral shape of individual galaxies, as well as to detect differences in luminosity in them, corresponding to especially large and bright star clusters.

However, the controversy lasted until the 20th century. Although it was already accepted in the progressive scientific community that there were many other galaxies besides the Milky Way, official academic astronomy needed irrefutable evidence of this. Therefore, the eyes of telescopes from all over the world are on the nearest large galaxy to us, which was also previously mistaken for a nebula - the Andromeda galaxy.

In 1888, the first photograph of Andromeda was taken by Isaac Roberts, and additional photographs were taken during the years 1900-1910. They show a bright galactic core, and even individual clusters of stars. But the low resolution of the images allowed errors. What were thought to be star clusters could have been nebulae, or simply a few stars "stuck together" into one during the exposure of the image. But the final solution of the issue was not far off.

Modern painting

In 1924, using the record telescope of the beginning of the century, Edwin Hubble was able to more or less accurately estimate the distance to the Andromeda galaxy. It turned out to be so huge that it completely ruled out that the object belonged to the Milky Way (despite the fact that Hubble's estimate was three times less than the modern one). Another astronomer discovered many stars in the "nebula", which clearly confirmed the galactic nature of Andromeda. In 1925, despite the criticism of colleagues, Hubble presented the results of his work at a conference of the American Astronomical Society.

This speech gave rise to a new period in the history of astronomy - scientists "rediscovered" nebulae, giving them the title of galaxies, and discovered new ones. In this they were helped by the developments of Hubble himself - for example, the discovery. The number of known galaxies grew with the construction of new telescopes and the launch of new ones - for example, the beginning wide application radio telescopes after World War II.

However, until the 90s of the XX century, humanity remained in the dark about the real number of galaxies surrounding us. The atmosphere of the Earth prevents even the largest telescopes from getting an accurate picture - the gas shells distort the image and absorb the light of stars, closing the horizons of the Universe from us. But scientists managed to get around these limitations by launching a space one, named after an astronomer you already know.

Thanks to this telescope, people for the first time saw the bright disks of those galaxies that previously seemed to be small nebulae. And where the sky used to seem empty, billions of new ones have appeared - and this is not an exaggeration. However, further studies have shown that even thousands of billions of stars visible to Hubble is at least a tenth of their real number.

final tally

And yet, exactly how many galaxies exist in the universe? I will immediately warn you that we will have to count together - such questions are usually of little interest to astronomers, since they are devoid of scientific value. Yes, they catalog and track galaxies - but only for more global purposes like studying the Universe.

However, no one undertakes to find the exact number. Firstly, our world is infinite, which is why the knowledge complete list galaxies is problematic and devoid of practical meaning. Secondly, to count even those galaxies that are within the visible universe, an astronomer does not have enough life. Even if he lives 80 years, starts counting galaxies from birth, and spends no more than a second to detect and register each galaxy, the astronomer will find only more than 2 billion objects - much less than there are galaxies in reality.

To determine the approximate number, let's take some of the high-precision studies of space - for example, the "Ultra Deep Field" of the Hubble telescope from 2004. In an area equal to 1/13,000,000 of the entire area of ​​the sky, the telescope was able to detect 10,000 galaxies. Considering that other in-depth studies of the time showed a similar picture, we can average the result. Therefore, within the sensitivity of Hubble, we see 130 billion galaxies from all over the universe.

However, that's not all. After "Ultra Deep Field" many other shots were taken that added new details. And not only in the visible spectrum of light, which Hubble operates, but also in infrared and X-ray. As of 2014, within a radius of 14 billion, 7 trillion 375 billion galaxies are available to us.

But this, again, is the minimum estimate. Astronomers believe that accumulations of dust in intergalactic space take away 90% of the observed objects from us - 7 trillion easily turns into 73 trillion. But even this figure will rush even further to infinity when a telescope enters the orbit of the Sun. This device will reach in minutes where the Hubble has been making its way for days, and will penetrate even further into the depths of the Universe.

Is the universe infinite, or does it have an edge? If it is infinite, this means that parallel universes must exist, says physicist Brian Greene.

He explained this idea in an interview with NPR using a metaphor: “Think of the universe as a deck of cards. If you shuffle the cards, there will be a lot of changes, says Brian Green. - If you shuffle this deck long enough, the card order may repeat itself. The same is true of the infinite universe. With a limited set of combinations of matter, the order of its arrangement must once be repeated.

According to him, many theoretical scientists are seriously considering the possibility of the existence of the Multiverse. Here are some of the existing hypotheses.

1. Bubble universes

Cosmologist Alexander Vilenkin from Tufts University believes that separate space zones after the Big Bang could expand, which led to the formation of isolated bubble universes.

According to Vilenkin's theory, our bubble stopped expanding, which created certain conditions in our universe. However, other bubbles may have continued to expand, causing physical properties those Universes are absolutely not similar to those that we observe in our Universe.

2. The universe as a hologram

String theory views the universe as a collection of very thin, vibrating strings. These strings create a force known as gravity. The string world is a kind of hologram projected from a lower cosmic dimension that is simpler, flatter and has no gravity.

3 A Huge Void In Space May Be A Door To Another Universe

A space void spanning 1 billion light-years baffled scientists when it was discovered in 2007. Then, in 2009, another space void spanning 3.5 billion light-years was discovered. Such a phenomenon cannot be explained by modern knowledge about the structure and evolution of the Universe. Voids of such gigantic proportions could not have formed in the time since the Big Bang. It would have taken much longer to educate them.

Physicist Laura Mersini-Hugton, a professor at the University of North Carolina, believes that this is a trace of another universe that is outside our universe. According to her hypothesis, quantum entanglement between our Universe and another Universe created these voids as a partition between the Universes.

4. Parallel universes that can collide with each other

The big bang that formed the universe could have been caused by the collision of two three-dimensional universes in another outer space. The Big Bang may be just one of many Big Bangs. The creation of the universe is a cyclic process, according to Paul Steinhard, professor of physics at Princeton University, and Neil Turok, director of the Perimeter Institute for Theoretical Physics in Ontario (Canada).

Their theory is partly based on superstring theory. In the preface to their book The Infinite Universe Beyond the Big Bang, they wrote: “We are convinced that the moment of creation was just part of an endless cycle of colossal collisions between our Universe and a parallel world.”

English version