Infinity definition
The Universe is the totality of everything that exists in the Cosmos. It is infinite in space because no one can designate its limits. It is eternal in time because it preceded the Big Bang, and after its cooling something will still happen and exist. The fundamental sciences study the individual components of the universe: chemistry explores the molecular world, physics explores elementary particles and atoms, biology is responsible for studying the phenomena of living nature. The structure of the Universe as a whole is studied by cosmology based on the theory of astronomy.
Models of the Universe
The rapid development of cybernetics in various scientific studies has led to the great popularity of modeling theory. The essence of this theory is to study the model corresponding to the original of a real object. Creating models of individual phenomena contributes to an in-depth study of the world. For a long time, astronomers have actively studied the structure of the Universe homogeneous and imaginary (isotronic).
A. Einstein proposed a cylindrical model in which certain local curvatures of time and space lead to a global curvature of the Universe. In this model, the coordinate of time does not bend, that is, time flows uniformly from the past to the future. Further, this model was improved by astrophysicist Willem de Setter, who suggested that against the background of redshift, time flows in different parts of the Universe in different ways.
Today, the most popular model of the expanding Universe proposed by Friedman. In this concept, the structure of the Universe has global curvature due to constantly gravitating masses. In the scientific world, two modifications of an expanding model are discussed:
- a closed model implies a phased deceleration of expansion as a result of gravitational inhibition;
- An open model implies a slowing expansion over an infinitely long time.
Any model of the Universe is just a copy of a real object, and therefore the results of its studies are purely theoretical, they require practical confirmation.
Galaxies in the universe
Today, Earth scientists observe only one Universe, but this is not the basis for the assertion that it is the only one. The structure and evolution of the universe is a global challenge for cosmological research. All its stars and celestial bodies are combined into huge stellar systems called galaxies. Each galaxy has a central core, spiral arms around it, in which a larger number of stars are located, and the periphery in the form of a cloud consisting of rare stars. Stars are born, live, moving in space, and die. In our Galaxy, the central star is the Sun, celestial bodies like him live from 10 to 15 billion years. Now the sun is in middle age.
The galaxy in which we live is called the Milky Way because its plane with the maximum number of stars, dust and gas is visible in the night sky as a foggy glow. The band of this glow surrounds the entire sky with a wide ring. The Milky Way is far from the only galaxy that makes up the structure of the Universe. There are a huge number of galaxies with countless stars. For example, the Andromeda Nebula and the Magellanic Clouds, located at an unimaginable distance from us.
The structure of the distribution of matter
The structure of the Universe is an accumulation of flat galactic sheets separated by regions in which luminous matter is practically absent. These voids are about 100 megaparsec in size. The first observed leaf is the Great Wall, located at a distance of 200 million light-years. The Great Wall is a group of galaxies with a thickness of 15 million St. years and sizes - 500 million St. years.
In the structure of the Universe, the position of the Earth has the following characteristics: the solar planetary system, the local group of clusters and superclusters of galaxies, the Orion arm, the galaxy - the Milky Way.