The starry sky has long excited human imagination. Our distant ancestors tried to understand what kind of strange flickering dots were hanging above their heads. How many are there, where did they come from, do they influence earthly events? Man with ancient times tried to understand how the Universe in which he lives works.

Today we can only learn about how ancient people imagined the Universe from fairy tales and legends that have come down to us. It took centuries and millennia for the science of the Universe to emerge and strengthen, studying its properties and stages of development - cosmology. The cornerstones of this discipline are astronomy, mathematics and physics.

Today we understand the structure of the Universe much better, but each knowledge gained only gives rise to new questions. Studying atomic particles in a collider, observing life in the wild, landing an interplanetary probe on an asteroid can also be called studying the Universe, because these objects are part of it. Man is also part of our beautiful stellar Universe. By studying the solar system or distant galaxies, we learn more about ourselves.

Cosmology and objects of its study

The concept of the Universe itself does not have a clear definition in astronomy. In different historical periods and among different peoples, it had a number of synonyms, such as “space”, “world”, “universe”, “universum” or “celestial sphere”. Often, when speaking about processes occurring in the depths of the Universe, the term “macrocosm” is used, the opposite of which is the “microcosm” of the world of atoms and elementary particles.

On the difficult path of knowledge, cosmology often intersects with philosophy and even theology, and this is not surprising. The science of the structure of the Universe tries to explain when and how the universe arose, to unravel the mystery of the origin of matter, to understand the place of the Earth and humanity in the infinity of space.

Modern cosmology has two biggest problems. Firstly, the object of its study - the Universe - is unique, which makes it impossible to use statistical schemes and methods. In short, we do not know about the existence of other Universes, their properties, structure, so we cannot compare. Secondly, the duration of astronomical processes does not make it possible to conduct direct observations.

Cosmology is based on the postulate that the properties and structure of the Universe are the same for any observer, with the exception of rare cosmic phenomena. This means that matter in the Universe is distributed uniformly, and it has the same properties in all directions. It follows from this that the physical laws that work in part of the Universe can be extrapolated to the entire Metagalaxy.

Theoretical cosmology develops new models, which are then confirmed or refuted by observations. For example, the theory of the origin of the Universe as a result of an explosion was proven.

Age, size and composition

The scale of the Universe is amazing: it is much larger than we could have imagined twenty or thirty years ago. Scientists have already discovered about five hundred billion galaxies, and the number is constantly increasing. Each of them rotates around its own axis and moves away from the others at enormous speed due to the expansion of the Universe.

Quasar 3C 345, one of the brightest objects in the Universe, is located five billion light years away from us. The human mind cannot even imagine such distances. To a spaceship, moving at the speed of light, it would take a thousand years to fly around our Milky Way. It would take him 2.5 thousand years to get to the Andromeda Galaxy. But this is the closest neighbor.

When talking about the size of the Universe, we mean its visible part, also called the Metagalaxy. The more observational results we get, the further the boundaries of the Universe expand. Moreover, this happens simultaneously in all directions, which proves its spherical shape.

Our world appeared about 13.8 billion years ago as a result of the Big Bang, an event that gave birth to stars, planets, galaxies and other objects. This figure is the real age of the Universe.

Based on the speed of light, it can be assumed that its size is also 13.8 billion light years. However, in reality they are larger, because from the moment of birth the Universe has been continuously expanding. Some are moving at superluminal speeds, which is why a significant number of objects in the Universe will remain invisible forever. This limit is called the Hubble sphere or horizon.

The diameter of the Metagalaxy is 93 billion light years. We don't know what lies beyond the known universe. Perhaps there are more distant objects that are inaccessible today for astronomical observations. A significant part of scientists believe in the infinity of the Universe.

The age of the Universe has been repeatedly tested using various techniques and scientific instruments. It was last confirmed using the Planck orbital telescope. The available data are fully consistent with modern models of the expansion of the Universe.

What is the Universe made of? Hydrogen is the most abundant element in the Universe (75%), helium is in second place (23%), and the remaining elements account for an insignificant 2% of the total amount of matter. The average density is 10-29 g/cm3, a significant part of which is the so-called dark energy and matter. The ominous names do not indicate their inferiority; it’s just that dark matter, unlike ordinary matter, does not interact with electromagnetic radiation. Accordingly, we cannot observe it and make our conclusions only based on indirect signs.

Based on the above density, the mass of the Universe is approximately 6*1051 kg. It should be understood that this figure does not include the dark mass.

The structure of the universe: from atoms to galaxy clusters

Space is not just a huge void in which stars, planets and galaxies are evenly scattered. The structure of the Universe is quite complex and has several levels of organization, which we can classify according to the scale of objects:

1. Astronomical bodies in the Universe are usually grouped into systems. Stars often form pairs or are part of clusters that contain dozens or even hundreds of stars. In this respect, our Sun is quite atypical, since it does not have a “double”;
2. The next level of organization are galaxies. They can be spiral, elliptical, lenticular, irregular. Scientists do not yet fully understand why galaxies have different shapes. At this level we discover such wonders of the Universe as black holes, dark matter, interstellar gas, double stars. In addition to stars, their composition includes dust, gas, and electromagnetic radiation. Several hundred billion galaxies have been discovered in the known Universe. They often collide with each other. It's not like a car accident: the stars just get mixed up and change their orbits. Such processes take millions of years and lead to the formation of new star clusters;
3. Several galaxies form the Local Group. Ours, in addition to the Milky Way, includes the Triangulum Nebula, the Andromeda Nebula and 31 other systems. Galaxy clusters are the largest known stable structures in the Universe; they are held together by gravitational force and some other factor. Scientists have calculated that attraction alone is clearly not enough to maintain the stability of these objects. There is no scientific basis for this phenomenon yet;
4. The next level of the structure of the Universe are superclusters of galaxies, each of which contains tens or even hundreds of galaxies and clusters. However, gravity no longer holds them back, so they follow the expanding Universe;
5. The last level of organization of the universe are cells or bubbles, the walls of which form superclusters of galaxies. Between them are empty areas called voids. These structures of the Universe have scales of about 100 Mpc. At this level, the processes of expansion of the Universe are most noticeable, and relict radiation is also associated with it - an echo of the Big Bang.

How the universe came into being

How did the Universe come into being? What happened before this moment? How did it become the endless space we know today? Was this an accident or a natural process?

After decades of discussion and fierce debate, physicists and astronomers have almost reached a consensus that the universe appeared as a result of an explosion of colossal power. He not only gave birth to all the matter in the Universe, but also determined the physical laws by which the cosmos known to us exists. It's called the Big Bang theory.

According to this hypothesis, all matter was once in some incomprehensible way collected in one small point with infinite temperature and density. It was called the singularity. 13.8 billion years ago, the point exploded, forming stars, galaxies, their clusters and other astronomical bodies of the Universe.

Why and how this happened is unclear. Scientists have to put aside many questions related to the nature of the singularity and its origin: complete physical theory This stage of the history of the Universe does not yet exist. It should be noted that there are other theories of the origin of the Universe, but they have much fewer adherents.

The term “Big Bang” came into use in the late 40s after the publication of the works of British astronomer Hoyle. Today, this model has been thoroughly developed - physicists can confidently describe the processes that occurred a fraction of a second after this event. We can also add that this theory made it possible to determine the exact age of the Universe and describe the main stages of its evolution.

The main evidence for the Big Bang theory is the presence of cosmic microwave background radiation. It was opened in 1965. This phenomenon arose as a result of the recombination of hydrogen atoms. CMB radiation can be called the main source of information about how the Universe was structured billions of years ago. It is isotropic and uniformly fills outer space.

Another argument in favor of the objectivity of this model is the very fact of the expansion of the Universe. As a matter of fact, by extrapolating this process into the past, scientists came to a similar concept.

There are also weaknesses in the Big Bang theory. If the universe was formed instantly from one small point, then there should have been a non-uniform distribution of matter, which we do not observe. Also, this model cannot explain where the antimatter went, the amount of which at the “moment of creation” should not have been inferior to ordinary baryonic matter. However, now the number of antiparticles in the Universe is tiny. But the most significant drawback of this theory is its inability to explain the Big Bang phenomenon; it is simply perceived as a fait accompli. We don't know what the Universe looked like before the singularity.

There are other hypotheses of the origin and further evolution of the universe. For many years, the model of a stationary Universe was popular. A number of scientists were of the opinion that as a result of quantum fluctuations it arose from a vacuum. Among them was the famous Stephen Hawking. Lee Smolin put forward the theory that ours, like other Universes, formed inside black holes.

Attempts have been made to improve the existing Big Bang theory. For example, there is a hypothesis about the cyclical nature of the Universe, according to which birth from a singularity is nothing more than its transition from one state to another. True, this approach contradicts the second law of thermodynamics.

The evolution of the universe or what happened after the Big Bang

The Big Bang theory allowed scientists to create an accurate model of the evolution of the Universe. And today we know quite well what processes took place in the young Universe. The only exception is the earliest stage of creation, which continues to be the subject of fierce discussion and debate. Of course, to achieve such a result, one theoretical basis was not enough; it took years of research into the Universe and thousands of experiments at accelerators.

Today science identifies the following stages after the Big Bang:

1. The earliest period known to us is called the Planck era, it occupies the interval from 0 to 10-43 seconds. At this time, all the matter and energy of the Universe was collected at one point, and the four main forces were one;
2. The era of the Great Unification (from 10−43 to 10−36 seconds). It is characterized by the appearance of quarks and the separation of the main types of interactions. The main event of this period is considered to be the release of gravitational force. During this era, the laws of the Universe began to form. Today we have the opportunity to detailed description physical processes of this era;
3. The third stage of creation is called the Age of Inflation (from 10−36 to 10−32). At this time, the rapid movement of the Universe began at a speed significantly exceeding that of light. It becomes larger than the current visible Universe. Cooling begins. During this period, they are finally separated fundamental forces of the universe;
4. In the period from 10−32 to 10−12 seconds, “exotic” particles such as the Higgs boson appear, and quark-gluon plasma filled the space. The interval from 10−12 to 10−6 seconds is called the era of quarks, from 10−6 to 1 second - hadrons, at 1 second after the Big Bang the era of leptons begins;
5. Nucleosynthesis phase. It lasted until about the third minute from the start of events. During this period, atoms of helium, deuterium, and hydrogen arise from particles in the Universe. Cooling continues, space becomes transparent to photons;
6. Three minutes after the Big Bang, the era of Primary Recombination begins. During this period, relict radiation appeared, which astronomers are still studying;
7. The period of 380 thousand - 550 million years is called the Dark Ages. The universe at this time is filled with hydrogen, helium, various types radiation. There were no light sources in the Universe;
8. 550 million years after Creation, stars, galaxies and other wonders of the Universe appear. The first stars explode, releasing matter to form planetary systems. This period is called the Era of Reionization;
9. At the age of 800 million years, the first star systems with planets. The Age of Substance is coming. During this period, our home planet was formed.

It is believed that the period from 0.01 seconds after the act of creation to the present day is of interest for cosmology. During this time period, the primary elements were formed, from which stars, galaxies, and the Solar system arose. For cosmologists, the era of recombination is considered a particularly important period, when relict radiation arose, with the help of which the study of the known Universe continues.

History of cosmology: the earliest period

Man has been thinking about the structure of the world around him since time immemorial. The earliest ideas about the structure and laws of the Universe can be found in fairy tales and legends of different peoples of the world.

It is believed that regular astronomical observations first began to be practiced in Mesopotamia. Several developed civilizations successively lived on this territory: Sumerians, Assyrians, Persians. We can learn about how they imagined the Universe from many cuneiform tablets found on the sites of ancient cities. The first records concerning the movement of celestial bodies date back to the 6th millennium BC.

Of the astronomical phenomena, the Sumerians were most interested in cycles - the changes of seasons and phases of the moon. The future harvest and the health of domestic animals, and therefore the survival of the human population, depended on them. From this, a conclusion was drawn about the influence of celestial bodies on processes occurring on Earth. Therefore, by studying the Universe, you can predict your future - this is how astrology was born.

The Sumerians invented a pole to determine the height of the Sun, created a solar and lunar calendar, described the main constellations, and discovered some laws of celestial mechanics.

Much attention was paid to the movement of cosmic objects in religious practices Ancient Egypt. The inhabitants of the Nile Valley used a geocentric model of the Universe, in which the Sun revolved around the Earth. Many ancient Egyptian texts containing astronomical information have reached us.

The science of the sky reached significant heights in Ancient China. Here, back in the 3rd millennium BC. e. the position of court astronomer appeared, and in the 12th century BC. e. The first observatories were opened. About solar eclipses, passages of comets, meteor showers and other interesting space events We mainly know about antiquity from Chinese annals and chronicles, which were scrupulously kept for centuries.

Astronomy was held in high esteem by the Hellenes. They studied this issue with numerous philosophical schools, each of which, as a rule, had its own system of the Universe. The Greeks were the first to propose the spherical shape of the Earth and the rotation of the planet around its own axis. The astronomer Hipparchus introduced the concepts of apogee and perigee, orbital eccentricity, developed models of the movement of the Sun and Moon, and calculated the periods of revolution of the planets. Ptolemy, who can be called the creator of the geocentric model of the solar system, made a great contribution to the development of astronomy.

The Mayan civilization reached great heights in the study of the laws of the Universe. This is confirmed by the results of archaeological excavations. The priests knew how to predict solar eclipses, they created a perfect calendar, built numerous observatories. Mayan astronomers observed nearby planets and were able to accurately determine their orbital periods.

Middle Ages and Modern Times

After the collapse of the Roman Empire and the spread of Christianity, Europe plunged into Dark Ages- development natural sciences, including astronomy, has practically stopped. Europeans drew information about the structure and laws of the Universe from biblical texts; a few astronomers firmly adhered to geocentric system Ptolemy, astrology enjoyed unprecedented popularity. The real study of the Universe by scientists began only during the Renaissance.

At the end of the 15th century, Cardinal Nicholas of Cusa put forward a bold idea about the universality of the universe and the infinity of the depths of the Universe. Already by XVI century It became clear that Ptolemy’s views were erroneous, and without the adoption of a new paradigm, further development of science was unthinkable. The Polish mathematician and astronomer Nicolaus Copernicus decided to break the old model, proposing a heliocentric model of the solar system.

From a modern point of view, his concept was flawed. For Copernicus, the movement of the planets was ensured by the rotation of the celestial spheres to which they were attached. The orbits themselves had a circular shape, and at the border of the world there was a sphere with fixed stars. However, by placing the Sun at the center of the system, the Polish scientist, without a doubt, made a real revolution. The history of astronomy can be divided into two large parts: ancient period and the study of the Universe from Copernicus to the present day.

In 1608, the Italian scientist Galileo invented the world's first telescope, which gave a huge impetus to the development of observational astronomy. Now scientists could contemplate the depths of the Universe. It turned out that the Milky Way consists of billions of stars, the Sun has spots, the Moon has mountains, and satellites revolve around Jupiter. The advent of the telescope caused a real boom in optical observations of the wonders of the Universe.

In the mid-16th century, the Danish scientist Tycho Brahe was the first to begin regular astronomical observations. He proved the cosmic origin of comets, thereby disproving Copernicus's idea of celestial spheres. IN early XVII century, Johannes Kepler unraveled the mysteries of planetary motion by formulating his famous laws. At the same time, the Andromeda and Orion nebulae and the rings of Saturn were discovered, and the first map of the lunar surface was compiled.

In 1687, Isaac Newton formulated the law universal gravity, explaining the interaction of all components of the Universe. He let me see hidden meaning Kepler's laws, which, in fact, were derived empirically. The principles discovered by Newton allowed scientists to take a new look at the space of the Universe.

The 18th century was a period of rapid development of astronomy, significantly expanding the boundaries of the known Universe. In 1785, Kant came up with the brilliant idea that the Milky Way was a huge cluster of stars pulled together by gravity.

At this time, new celestial bodies appeared on the “map of the Universe” and telescopes were improved.

In 1785, the English astronomer Herschel, based on the laws of electromagnetism and Newtonian mechanics, tried to create a model of the Universe and determine its shape. However, he failed.

In the 19th century, scientists' instruments became more precise, and photographic astronomy appeared. Spectral analysis, which appeared in the middle of the century, led to a real revolution in observational astronomy - now the topic for research has become chemical composition objects. The asteroid belt was discovered and the speed of light was measured.

The era of breakthroughs or modern times

The twentieth century was an era of real breakthroughs in astronomy and cosmology. At the beginning of the century, Einstein revealed to the world his theory of relativity, which made a real revolution in our ideas about the universe and allowed us to take a fresh look at the properties of the Universe. In 1929, Edwin Hubble discovered that our Universe is expanding. In 1931, Georges Lemaitre put forward the idea of ​​its formation from one tiny point. In essence, this was the beginning of the Big Bang theory. In 1965, cosmic microwave background radiation was discovered, confirming this hypothesis.

The first was sent into orbit in 1957 artificial satellite, after which the space age began. Now astronomers could not only observe celestial bodies through telescopes, but also study them up close using interplanetary stations and lander probes. We were even able to land on the surface of the Moon.

The 90s can be called the “dark matter period.” Her discovery explained the acceleration of the expansion of the Universe. During this time, new telescopes were introduced, allowing us to push the limits of the known Universe.

In 2016, gravitational waves were discovered, which will likely mark the beginning of a new branch of astronomy.

Behind last centuries we have significantly expanded the boundaries of our knowledge of the Universe. However, in fact, people only opened the door slightly and looked into the huge and amazing world, full of secrets and amazing miracles.

If you have any questions, leave them in the comments below the article. We or our visitors will be happy to answer them

in natural science

Subject: Modern science about the origin of the Universe.

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Introduction 3

Pre-scientific consideration of the origin of the Universe. 5

20th century theories about the origin of the Universe. 8

Modern science about the origin of the Universe. 12

Literature used: 18

Throughout his existence, Man studies the world around him. Being a thinking being, Man, both in the distant past and now, could not and cannot limit himself to what was directly given to him at the level of his everyday life. practical activities, and has always strived and will strive to go beyond its limits.

It is characteristic that man’s knowledge of the surrounding world began with cosmogonic reflections. It was then, at the dawn of mental activity, that the idea of ​​“the beginning of all beginnings” arose. History does not know a single nation that, sooner or later, in one form or another, did not ask this question and try to answer it. The answers, of course, were different, depending on the level of spiritual development of a given people. Development of human thought, scientific and technical progress allowed us to advance in resolving the question of the origin of the Universe from mythological thinking to the construction of scientific theories.

The problem of the “beginning of the world” is one of those few ideological problems that run through the entire intellectual history humanity. Appearing once on White light, the idea of ​​the “beginning of the world” has since always occupied the thoughts of scientists and from time to time in one guise or another resurfaces again and again. So, seemingly buried forever during the Middle Ages, it unexpectedly appeared on the horizon of scientific thought in the second half of the twentieth century and began to be seriously discussed on the pages of special journals and at meetings of problem symposia.

Over the past century, the science of the Universe has reached the very top floors structural organization matter - galaxies, their clusters and superclusters. Modern cosmology has actively taken up the problem of the origin (formation) of these cosmic formations.

How did our distant ancestors imagine the formation of the Universe? How does modern science explain the origin of the Universe? This paper is devoted to the consideration of these and other questions related to the emergence of the Universe.

Where did it all start? How did everything cosmic become the way it appears to humanity? What were the initial conditions that gave rise to the observable Universe?

The answer to these questions has changed with the development of human thought. Among ancient peoples, the origin of the Universe was endowed with a mythological form, the essence of which boils down to one thing - a certain deity created the entire surrounding Man world. In accordance with the ancient Iranian mythopoetic cosmogony, the Universe is the result of the activity of two equivalent and interconnected creative principles - the god of Good - Ahuramazda and the god of Evil - Ahriman. According to one of its texts, the primordial being, the division of which led to the formation of parts of the visible Universe, was the originally existing Cosmos. The mythological form of the origin of the Universe is inherent in all existing religions.

Many outstanding thinkers from historical eras far from us tried to explain the origin, structure and existence of the Universe. Their attempts in the absence of modern ones deserve special respect. technical means using only your mind and the simplest devices to comprehend the essence of the Universe. If you take a short excursion into the past, you will find that the idea of ​​an evolving Universe, adopted by modern scientific thought, was put forward by the ancient thinker Anaxagoras (500-428 BC). The cosmology of Aristotle (384-332 BC), and the works of the outstanding thinker of the East Ibn Sina (Avicenna) (980-1037), who tried to logically refute the divine creation of the world, and other names that have survived to our time, also deserve attention.

Human thought does not stand still. Along with the change in the idea of ​​the structure of the Universe, the idea of ​​its origin also changed, although in the conditions of the existing strong ideological power of religion this was associated with a certain danger. This may explain the fact that the natural sciences of modern European times avoided discussing the question of the origin of the Universe and focused on studying the structure of the Near Space. This scientific tradition for a long time determined the general direction and methodology of astronomical and then astrophysical research. As a result, the foundations of scientific cosmogony were laid not by natural scientists, but by philosophers.

The first to take this path was Descartes, who tried to theoretically reproduce “the origin of the luminaries, the Earth and everything else.” visible world as if from some seeds" and give a unified mechanical explanation of the entire set of astronomical, physical and biological phenomena known to him. However, Descartes' ideas were far from his contemporary science.

Therefore, it would be more fair to begin the history of scientific cosmogony not with Descartes, but with Kant, who painted a picture of the “mechanical origin of the entire universe.” It was Kant who owned the first scientific-cosmogonic hypothesis about the natural mechanism of the emergence of the material world. In the boundless space of the Universe, recreated by Kant’s creative imagination, the existence of countless other solar systems and other milky way as natural as continuing education new worlds and the death of old ones. It is with Kant that the conscious and practical connection of the principle of universal connection and unity of the material world begins. The universe has ceased to be a collection of divine bodies, perfect and eternal. Now, before the astonished human mind, a world harmony of a completely different kind appeared - the natural harmony of systems of interacting and evolving astronomical bodies, connected to each other as links in one chain of nature. However, it is necessary to note two characteristics further development scientific cosmogony. The first of these is that post-Kantian cosmogony limited itself to the boundaries of the solar system and, until the middle of the twentieth century, it was only about the origin of the planets, while the stars and their systems remained beyond the horizon theoretical analysis. The second feature is that the limitations of observational data, the uncertainty of available astronomical information, the impossibility experimental substantiation cosmogonic hypotheses ultimately led to the transformation of scientific cosmogony into a system of abstract ideas, divorced not only from other branches of natural science, but also from related branches of astronomy.

The next stage in the development of cosmology dates back to the twentieth century, when the Soviet scientist A.A. Friedman (1888-1925) mathematically proved the idea of ​​a self-developing Universe. The work of A.A. Friedman radically changed the foundations of the previous scientific worldview. According to him, the cosmological initial conditions for the formation of the Universe were singular. Explaining the nature of the evolution of the Universe, expanding starting from a singular state, Friedman especially highlighted two cases:

a) the radius of curvature of the Universe constantly increases over time, starting from zero;

b) the radius of curvature changes periodically: the Universe contracts into a point (into nothing, a singular state), then again from a point, brings its radius to a certain value, then again, reducing the radius of its curvature, turns into a point, etc.

In a purely mathematical sense, a singular state appears as nothingness - a geometric entity of zero size. In physical terms, singularity appears as a very peculiar state in which the density of matter and the curvature of space-time are infinite. All super-hot, super-curved and super-dense cosmic matter is literally pulled into a point and can, in the figurative expression of the American physicist J. Wheeler, “squeeze through the eye of a needle.”

Moving on to the assessment modern look on the singular beginning of the Universe, it is necessary to pay attention to the following important features of the problem under consideration as a whole.

Firstly, the concept of initial singularity has a fairly specific physical content, which is increasingly detailed and refined as science develops. In this regard, it should be considered not as a conceptual fixation of the absolute beginning of “all things and events,” but as the beginning of the evolution of that fragment of cosmic matter, which at the modern level of development of natural science has become an object of scientific knowledge.

Secondly, if, according to modern cosmological data, the evolution of the Universe began 15-20 billion years ago, this does not mean at all that before that the Universe did not yet exist or was in a state of eternal stagnation.

Achievements of science have expanded the possibilities of understanding the world around Man. New attempts have been made to explain how it all began. Georges Lemaitre was the first to raise the question of the origin of the observed large-scale structure of the Universe. He put forward the concept of the “Big Bang” of the so-called “primordial atom” and the subsequent transformation of its fragments into stars and galaxies. Of course, from the height of modern astrophysical knowledge, this concept is of only historical interest, but the very idea of ​​the initial explosive movement of cosmic matter and its subsequent evolutionary development has become an integral part of the modern scientific picture of the world.

Fundamentally new stage in the development of modern evolutionary cosmology is associated with the name of the American physicist G. A. Gamov (1904-1968), thanks to whom the concept of a hot Universe entered science. According to his proposed model of the “beginning” of the evolving Universe, Lemaitre’s “primary atom” consisted of highly compressed neutrons, the density of which reached a monstrous value - one cubic centimeter of the primary substance weighed a billion tons. As a result of the explosion of this “first atom,” according to G.A. Gamov, a unique cosmological cauldron with a temperature of about three billion degrees was formed, where natural synthesis took place chemical elements. Fragments of the primary egg - individual neutrons - then decayed into electrons and protons, which, in turn, combined with undecayed neutrons to form the nuclei of future atoms. All this happened in the first 30 minutes after the Big Bang.

The hot model was a specific astrophysical hypothesis that indicated ways to experimentally verify its consequences. Gamow predicted the current existence of remnants of thermal radiation from the primordial hot plasma, and his collaborators Alfer and Hermann, back in 1948, quite accurately calculated the temperature of this residual radiation already modern universe. However, Gamow and his collaborators failed to give a satisfactory explanation of the natural formation and prevalence of heavy chemical elements in the Universe, which was the reason for the skeptical attitude towards his theory on the part of specialists. As it turned out, the proposed mechanism of nuclear fusion could not provide the currently observed quantities of these elements.

Scientists began to look for other physical models of the “beginning”. In 1961, Academician Ya.B. Zeldovich put forward an alternative cold model, according to which the original plasma consisted of a mixture of cold (with a temperature below absolute zero) degenerate particles - protons, electrons and neutrinos. Three years later, astrophysicists I.D. Novikov and A.G. Doroshkevich produced comparative analysis two opposite models of cosmological initial conditions - hot and cold - and indicated the path to experimental verification and selection of one of them. It was proposed to try to detect the remnants of primary radiation by studying the spectrum of radiation from stars and cosmic radio sources. The discovery of remnants of primary radiation would confirm the correctness of the hot model, and if they do not exist, then this would indicate in favor of the cold model.

Almost at the same time, a group of American researchers led by physicist Robert Dicke, unaware of the published results of the work of Gamow, Alpher and Hermann, revived the hot model of the Universe based on other theoretical considerations. Through astrophysical measurements, R. Dicke and his collaborators found confirmation of the existence of cosmic thermal radiation. This epoch-making discovery made it possible to obtain important, previously unavailable information about the initial stages of the evolution of the astronomical Universe. The registered cosmic microwave background radiation is nothing more than a direct radio report about unique universal events that took place shortly after the “Big Bang” - the most grandiose in its scale and consequences of the catastrophic process in observable history Universe.

Thus, as a result of recent astronomical observations, it was possible to unambiguously resolve the fundamental question about the nature of the physical conditions that prevailed in the early stages of cosmic evolution: the hot model of the “beginning” turned out to be the most adequate. What has been said, however, does not mean that all theoretical statements and conclusions of Gamow’s cosmological concept were confirmed. Of the two initial hypotheses of the theory - about the neutron composition of the “cosmic egg” and the hot state of the young Universe - only the latter has stood the test of time, indicating the quantitative predominance of radiation over matter at the origins of the currently observed cosmological expansion.

At the current stage of development of physical cosmology, the task of creating the thermal history of the Universe, especially the scenario for the formation of the large-scale structure of the Universe, has come to the fore.

Recent theoretical research by physicists has been carried out in the direction of the following fundamental idea: all known types of physical interactions are based on one universal interaction; electromagnetic, weak, strong and gravitational interactions are different facets of a single interaction, which splits as the energy level of the corresponding physical processes decreases. In other words, at very high temperatures (exceeding certain critical values), various types of physical interactions begin to combine, and at the limit, all four types of interaction are reduced to a single proto-interaction, called the “Great Synthesis”.

According to quantum theory, what remains after particles of matter are removed (for example, from a closed container using a vacuum pump) is not empty at all. literally words, as classical physics believed. Although the vacuum does not contain ordinary particles, it is saturated with “half-living”, so-called virtual bodies. To turn them into real particles of matter, it is enough to excite the vacuum, for example, by influencing it with an electromagnetic field created by charged particles introduced into it.

But what exactly caused the “Big Bang”? According to astronomy data physical quantity The cosmological constant that appears in Einstein's equations of gravity is very small, perhaps close to zero. But even being so insignificant, it can cause very large cosmological consequences. The development of quantum field theory has led to even more interesting conclusions. It turned out that the cosmological constant is a function of energy, in particular it depends on temperature. At ultra-high temperatures that prevailed in the earliest phases of the development of cosmic matter, the cosmological constant could be very large, and most importantly, positive in sign. In other words, in the distant past, the vacuum could be in an extremely unusual physical condition characterized by the presence of powerful repulsive forces. It was these forces that served as the physical cause of the “Big Bang” and the subsequent rapid expansion of the Universe.

A consideration of the causes and consequences of the cosmological “Big Bang” would not be complete without one more physical concept. We are talking about the so-called phase transition (transformation), i.e. qualitative transformation of a substance, accompanied by a sharp change from one state to another. Soviet physicists D.A. Kirzhnits and A.D. Linde were the first to draw attention to the fact that in the initial phase of the formation of the Universe, when cosmic matter was in a super-hot, but already cooling state, similar events could occur physical processes(phase transitions).

Further study of the cosmological consequences of phase transitions with broken symmetry led to new theoretical discoveries and generalizations. Among them is the discovery of a previously unknown era in the self-development of the Universe. It turned out that during a cosmological phase transition it could reach a state of extremely rapid expansion, in which its size increased many times, but the density of matter remained practically unchanged. The initial state that gave rise to the inflating Universe is considered to be a gravitational vacuum. The sharp changes accompanying the process of cosmological expansion of space are characterized by fantastic figures. Thus, it is assumed that the entire observable Universe arose from a single vacuum bubble measuring less than 10 to the minus 33 degree cm! The vacuum bubble from which our Universe was formed had a mass equal to only one hundred thousandth of a gram.

At present, there is still no comprehensively tested and universally accepted theory of the origin of the large-scale structure of the Universe, although scientists have made significant progress in understanding natural ways its formation and evolution. Since 1981, the development of a physical theory of an inflating (inflationary) Universe began. To date, physicists have proposed several versions of this theory. It is assumed that the evolution of the Universe, which began with a grandiose cosmic cataclysm called the “Big Bang,” was subsequently accompanied by repeated changes in the expansion regime.

According to scientists' assumptions, 10 to the minus forty-third degree of seconds after the "Big Bang" the density of super-hot cosmic matter was very high (10 to the 94th degree grams/cm cubic). The density of the vacuum was also high, although in order of magnitude it was much lower than the density of ordinary matter, and therefore the gravitational effect of the primeval physical “emptiness” was invisible. However, during the expansion of the Universe, the density and temperature of matter fell, while the density of the vacuum remained unchanged. This circumstance led to a sharp change in the physical situation already 10 to minus 35 seconds after the “Big Bang”. The density of the vacuum is first compared, and then, after several super-instants of cosmic time, it becomes greater than it. Then the gravitational effect of the vacuum makes itself felt - its repulsive forces again take precedence over the gravitational forces of ordinary matter, after which the Universe begins to expand at an extremely fast pace (inflates) and in an infinitesimal fraction of a second reaches enormous sizes. However, this process is limited in time and space. The Universe, like any expanding gas, first cools quickly and is already severely supercooled around 10 to minus 33 seconds after the Big Bang. As a result of this universal “cooling,” the Universe moves from one phase to another. We are talking about a phase transition of the first kind - an abrupt change in the internal structure of cosmic matter and all related to it physical properties and characteristics. At the final stage of this cosmic phase transition, the entire energy reserve of the vacuum turns into thermal energy ordinary matter, and as a result, the universal plasma is again heated to its original temperature, and accordingly the regime of its expansion changes.

No less interesting, and from a global perspective more important, is another result of the latest theoretical research - the fundamental possibility of avoiding the initial singularity in its physical sense. We are talking about a completely new physical view of the problem of the origin of the Universe.

It turned out that, contrary to some recent theoretical predictions (that the initial singularity cannot be avoided even with quantum generalization general theory relativity) there are certain microphysical factors that can prevent the infinite compression of matter under the influence of gravitational forces.

Back in the late thirties, it was theoretically discovered that stars with a mass exceeding the mass of the Sun by more than three times, at the last stage of their evolution, are uncontrollably compressed to a singular state. The latter, in contrast to the singularity of the cosmological type, called Friedmann's, is called Schwarzschild (named after the German astronomer who first considered the astrophysical consequences of Einstein's theory of gravity). But from a purely physical point of view, both types of singularity are identical. Formally, they differ in that the first singularity is the initial state of the evolution of matter, while the second is the final state.

According to recent theoretical concepts, gravitational collapse should end with the compression of matter literally “to a point” - to a state of infinite density. According to the latest physical concepts, the collapse can be stopped somewhere in the region of the Planck density value, i.e. at the turn of 10 to the 94th degree gram/cm cubic. This means that the Universe resumes its expansion not from scratch, but having a geometrically defined (minimum) volume and a physically acceptable, regular state.

Academician M.A. Markov put forward an interesting version of a pulsating Universe. In the logical framework of this cosmological model, old theoretical difficulties, if not completely resolved, are at least illuminated from a new promising angle. The model is based on the hypothesis that with a sharp decrease in distance, the constants of all physical interactions tend to zero. This assumption is a consequence of another assumption, according to which the gravitational interaction constant depends on the degree of density of the substance.

According to Markov's theory, whenever the Universe moves from the Friedmann stage (final compression) to the De Sitter stage (initial expansion), its physical and geometric characteristics turn out to be the same. Markov believes that this condition is quite sufficient to overcome the classical difficulty on the way to the physical realization of an eternally oscillating Universe.

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Science of Celestial Bodies

The first letter is "a"

Second letter "s"

Third letter "t"

The last letter is "I"

Answer for the question "Science of celestial bodies", 10 letters:
astronomy

Alternative crossword questions for the word astronomy

What did the muse Urania patronize?

Universe Science

Caroline Herschel assisted her brother William from 1782 and became one of the first women in this science

One of the seven liberal sciences

Definition of the word astronomy in dictionaries

Dictionary Russian language. S.I.Ozhegov, N.Yu.Shvedova. The meaning of the word in the dictionary Explanatory Dictionary of the Russian Language. S.I.Ozhegov, N.Yu.Shvedova.
-i, f. Science of cosmic bodies ah, the systems they form and about the Universe as a whole. adj. astronomical, -aya, -oh. Astronomical unit (distance from the Earth to the Sun). Astronomical number (translated: extremely large).

encyclopedic Dictionary, 1998 The meaning of the word in the dictionary Encyclopedic Dictionary, 1998
ASTRONOMY (from astro... and Greek nomos - law) is the science of the structure and development of cosmic bodies, the systems they form and the Universe as a whole. Astronomy includes spherical astronomy, practical astronomy, astrophysics, celestial mechanics, stellar astronomy,...

Explanatory dictionary of the Russian language. D.N. Ushakov The meaning of the word in the dictionary Explanatory Dictionary of the Russian Language. D.N. Ushakov
astronomy, many no, w. (from Greek astron - star and nomos - law). The science of celestial bodies.

New explanatory and word-formative dictionary of the Russian language, T. F. Efremova. The meaning of the word in the dictionary New explanatory dictionary of the Russian language, T. F. Efremova.
and. A complex scientific discipline that studies the structure and development of cosmic bodies, their systems and the Universe as a whole. Academic subject containing theoretical basis of this scientific discipline. decomposition A textbook setting out the content of a given subject.

Big Soviet Encyclopedia The meaning of the word in the dictionary Great Soviet Encyclopedia
“Astronomy”, abstract journal of the All-Union Institute of Scientific and Technical Information of the USSR Academy of Sciences. Published in Moscow since 1963 (in 1953–62 the abstract journal “Astronomy and Geodesy” was published); 12 issues per year. Publishes abstracts, annotations or bibliographic...

Examples of the use of the word astronomy in literature.

The ancient pilotage of the Sea of ​​Azov was adjacent to textbooks astronomy and navigation.

Just as these concrete problems, solved by algebraic techniques, cannot be considered part of the abstract science of algebra, so, in my opinion, the concrete problems astronomy cannot in any way be included in that department of abstract-concrete science that develops the theory of action and reaction free bodies, attracting each other.

This was the case with the discovery that the refraction and scattering of light do not follow the same law of change: this discovery had an impact both on astronomy, and on physiology, giving us achromatic telescopes and microscopes.

Soon Biruni begins to seriously engage in issues astronomy, having already achieved important results at the age of 21.

Matthew Vlastar is absolutely correct from the point of view astronomy explains this disturbance that arose over time.