Cosmology

The early forms of cosmology were religious myths about the creation ( cosmogony ) and destruction ( eschatology ) of the existing world.

China

Archaeological finds suggest that the prototype of space could be considered the shell of a land tortoise , whose shields divide the plane of the earth into squares.

In the earliest of the textually presented models of Chinese cosmology, it was believed that the Earth is covered by the sky like a canopy on a chariot , and this canopy rotates in the horizontal plane, like an umbrella (the so-called Gaitian蓋天 model, also called Zhoubi , by the name of a mathematical treatise, describing calculations according to this model). To ser. Han Dynasty, this model was disputed by astronomical observations. It was replaced by the idea of ​​the sphericity of the cosmos surrounding the Earth (model huntian浑天). OK. 180 g. e. Cai Yong also mentions the third model, Xuanju宣 夜 - however, information about it was not preserved by his time.

European Antiquity

Most of the ancient Greek scientists supported the geocentric system of the world , according to which in the center of the Universe there is a motionless spherical Earth, around which five planets, the Sun and the Moon , revolve. The heliocentric system of the world proposed by Aristarchus of Samos , apparently, did not receive the support of most ancient Greek astronomers.

The world was considered limited to the sphere of fixed stars ^[1] . Sometimes another sphere responsible for the precession was added. The subject of debate was the question of what is outside the world: the peripatetics after Aristotle believed that there was nothing outside (no matter, no space), the Stoics believed that there was infinite empty space, atomists ( Leucippus , Democritus , Metrodor , Epicurus , Lucretius ) believed that other worlds are outside our world. Apart are the views of Heraclides of Pontius , according to which the stars are distant worlds, including earth and air; he, like atomists, considered the universe to be infinite. At the sunset of antiquity, the religious-mystical doctrine of Hermeticism appeared , according to which outside the world there may be an area of ​​intangible creatures - spirits ^[2] .

Many pre-Socratics believed that the movement of the stars is controlled by a giant vortex that gave rise to the universe. However, after Aristotle, most ancient astronomers believed that planets are transported in their motion by material spheres, consisting of a special celestial element - the ether , whose properties have nothing to do with the elements of earth, water, air and fire that make up the “lunar world”. There was a widespread opinion about the divine nature of the celestial spheres or luminaries, their animation.

Middle Ages

In the Middle Ages, astronomy and philosophy of both Christian and Muslim countries was dominated by Aristotle's cosmology, supplemented by the Ptolemaic theory of planetary motion, together with an idea of ​​the material celestial spheres. Some philosophers of the XIII-XIV centuries. believed that the infinitely omnipotent God could create, in addition to ours, other worlds ^{[3] [4]} ; nevertheless, this possibility was considered purely hypothetical: although God could create other worlds, he did not. Some philosophers (for example, Thomas Bradwardin and Nikolai Orem ) believed that outside our world there is an infinite space that serves as the abode of God (a modification of the cosmology of the Hermetists, who also believed the extra-world space is related to the spiritual sphere ^[5] ).

Renaissance

The cosmology of Nikolai Kuzansky , set forth in the treatise On Scientist Ignorance , is innovative. He assumed the material unity of the Universe and considered the Earth to be one of the planets also moving; celestial bodies are inhabited, like our Earth, and each observer in the Universe with equal reason can consider himself motionless. In his opinion, the Universe is limitless, but finite, since infinity can be peculiar only to God. At the same time, Kuzanets retains many elements of medieval cosmology, including belief in the existence of celestial spheres, including the outer one - the sphere of fixed stars. However, these "spheres" are not absolutely round, their rotation is not uniform, the axis of rotation do not occupy a fixed position in space. As a result of this, the world does not have an absolute center and a clear boundary (probably in this sense it is necessary to understand the thesis of Kuzanets about the infinity of the Universe) ^[6] .

The first half of the 16th century was marked by the emergence of a new, heliocentric system of the world of Nicholas Copernicus. Copernicus placed the Sun in the center of the world, around which the planets revolved (including the Earth, which also made a rotation around its axis). Copernicus still considered the universe a limited sphere of fixed stars; apparently, his faith in the existence of celestial spheres was also preserved ^[7] .

A modification of the Copernican system was the Thomas Digges system, in which the stars are not located on one sphere, but at different distances from Earth to infinity. Some philosophers ( Francesco Patrici , Jan Essen ) borrowed only one element of the Copernican teaching - the rotation of the Earth around its axis, also considering the stars scattered throughout the universe to infinity. The views of these thinkers bear the traces of the influence of hermeticism, since the region of the Universe outside the solar system was considered by them to be an immaterial world, the habitat of God and angels ^{[8] [9] [10]} .

The decisive step from heliocentrism to an infinite universe uniformly filled with stars was made by the Italian philosopher Giordano Bruno . According to Bruno, when observed from all points, the Universe should look about the same. Of all the thinkers of the New Age, he was the first to suggest that the stars are distant suns and that the physical laws are the same in all infinite and unlimited space ^[11] . At the end of the 16th century, the infinity of the universe was also upheld by William Hilbert . In the middle - second half of the XVII century, these views were supported by Rene Descartes , Otto von Guericke and Christian Huygens .

The Emergence of Modern Cosmology

The emergence of modern cosmology is associated with the development in the 20th century of Einstein's general theory of relativity (GR) and elementary particle physics . The first study on this subject, based on general relativity, Einstein published in 1917 under the title "Cosmological considerations to the general theory of relativity." In it, he introduced 3 assumptions: the Universe is homogeneous, isotropic and stationary. To provide the last requirement, Einstein introduced an additional “ cosmological term ” into the equations of the gravitational field . His solution meant that the Universe has a finite volume (closed) and positive curvature .

In 1922, A. A. Fridman proposed a non-stationary solution of the Einstein equation , in which the isotropic Universe expanded from the initial singularity . The theory of the unsteady universe was confirmed by the discovery in 1929 by E. Hubble of the cosmological redshift of galaxies. Thus, the generally accepted theory of the Big Bang arose.

Age of the Universe

The age of the universe is the time elapsed since the Big Bang . According to modern scientific data ( WMAP results 9), it is 13.830 ± 0.075 billion years ^[12] . New data obtained using the powerful Planck satellite telescope owned by the European Space Agency show that the universe is 13.798 ± 0.037 billion years old (68% confidence interval ) ^{[13] [14] [15]} .

A modern estimate of the age of the Universe is based on one of the most common models of the Universe, the so-called standard cosmological ΛCDM model .

The main stages of the development of the universe

Of great importance for determining the age of the Universe is the periodization of the main processes taking place in the Universe. Currently adopted the following periodization ^[16] :

• The earliest era about which any theoretical assumptions exist is Planck time ( ^10–43 s after the Big Bang ). At this time, the gravitational interaction separated from the rest of the fundamental interactions . According to modern ideas, this era of quantum cosmology lasted until about 10 ⁻¹¹ s after the Big Bang.
• The next era is characterized by the birth of the initial particles of quarks and the separation of types of interactions. This era lasted until about 10 ⁻² s after the Big Bang. At present, there is already the possibility of a fairly detailed physical description of the processes of this period.
• The modern era of standard cosmology began 0.01 seconds after the Big Bang and continues to this day. During this period, nuclei of primary elements formed, stars, galaxies, the solar system arose.

An important milestone in the history of the development of the Universe in this era is the era of recombination , when the matter of the expanding Universe became transparent to radiation. According to modern ideas, this happened 380 thousand years after the Big Bang. At present, we can observe this radiation in the form of a relict background , which is the most important experimental confirmation of existing models of the Universe.

WMAP

WMAP (Wilkinson Microwave Anisotropy Probe) - NASA's spacecraft , designed to study the relict radiation generated by the Big Bang at the time of the birth of the universe .

The information collected by WMAP allowed scientists to build the most detailed map of temperature fluctuations in the distribution of microwave radiation in the celestial sphere to date. Previously, such a map was built according to NASA COBE , but its resolution was significantly - 35 times - inferior to the data obtained by WMAP.

WMAP data showed that the distribution of the CMB temperature over the celestial sphere corresponds to completely random fluctuations with a normal distribution . The parameters of the function that describes the measured distribution are consistent with the model of the Universe, consisting of:

• 4% of the usual substance,
• 23% from the so-called dark matter (possibly from hypothetical heavy supersymmetric particles ) and
• 73% of the even more mysterious dark energy causing the accelerated expansion of the universe.

WMAP data suggest that dark matter is cold (that is, it consists of heavy particles, not neutrinos or any other light particles). Otherwise, light particles moving with relativistic velocities would erode small density fluctuations in the early Universe.

Among other parameters, WMAP data were determined (based on the ΛCDM model, that is, the Friedmann cosmological model with the Λ term and the Cold Dark Matter ) ^[17] :

• age of the Universe : (13.73 ± 0.12) ⋅10 ⁹ years;
• Hubble constant : 71 ± 4 km / s / Mpc ;
• baryon density at present: (2.5 ± 0.1) ⋅ 10 ⁻⁷ cm ⁻³ ;
• flatness parameter of the Universe (ratio of total density to critical ): 1.02 ± 0.02;
• the total mass of all three types of neutrinos : <0.7 eV.

According to a review of Planck TT, TE, EE + lensing + BAO + JLA + H0

• 100 θ _MC = 1.04077 ± 0.00032
• Ω _b h ² = 0.02225 ± 0.00016
• Ω _c h ² = 0.1198 ± 0.0015
• τ = 0.079 ± 0.017
• ln (10 ¹⁰ As) = 3.094 ± 0.034
• n _s = 0.9645 ± 0.0049
• H ₀ = 67.27 ± 0.66
• Ω _m = 0.3089 ± 0.0062
• Ω _Λ = 0.6911 ± 0.0062
• Σm _v [eV] <0.17
• Ω _k = 0.0008 _−0.0039 ^+0.0040
• w = −1.019 _−0.08 ^+0.075

• Barker P. Copernicus, the orbs, and the equant . - Synthese. - 1990. - T. 83, no. 2. - P. 317-323.
• C. Bonneau, S. Brunier. Une sonde defie l'espace et le temps. Science & Vie, No. 1072, Janvier 2007, p. 43
• Furley, David J. The Greek Theory of the Infinite Universe // Journal of the History of Ideas. - 1981. - T. 42, No. 4 (Oct. - Dec.). - P. 571-585. .
• Gatti H. Giordano Bruno and Renaissance Science. - Cornell Univercity Press, 1999 .
• Gombrich, RF "Ancient Indian Cosmology." In Ancient Cosmologies, edited by Carmen Blacker and Michael Loewe, 110-142. London: Allen and Unwin, 1975.
• Granada, Miguel A. Kepler and Bruno on the Infinity of the Universe and of Solar Systems // Journal for the History of Astronomy. - 2008. - T. 39, No. 4. - P. 469-495.
• Grant E. Medieval and Seventeenth-Century Conceptions of an Infinite Void Space Beyond the Cosmos // Isis. - 1969. - T. 60, No. 201. - P. 39-60. .
• Grant E. Planets, Stars, and Orbs: The Medieval Cosmos, 1200-1687. - Cambridge, 1994 .
• Henderson, John B. The Development and Decline of Chinese Cosmology. Neo-Confucian Studies Series. New York: Columbia University Press, 1984 .-->
• McColley G. The seventeenth-century doctrine of a plurality of worlds // Annals of Science. - 1936. - No. 1. - P. 385–430. .
• Sircar DS Cosmography and Cosmology in Early Indian Literature. Calcutta, 1976 (1 ed .: Calcutta, 1967)

In Russian

• Bakina V.I. Cosmological doctrine of Heraclitus of Ephesus // Bulletin of Moscow University. Ser. 7. Philosophy .. 1998.№ 4. P.42-55.
• Bakina V. I. Cosmological teachings of early Greek philosophers: Textbook. allowance. M., Moscow Publishing House. un-that. 1999. −104 p.
• Weinberg S. The first three minutes: a modern view of the origin of the universe. - Izhevsk: Research Center “Regular and chaotic dynamics”, 2000, 272 p. ISBN 5-93972-013-7
• Gavryushin N.K. Byzantine cosmology in the XI century // Historical and astronomical studies . - M .: "Science", 1983. Issue XVI. S.325-338.
• Gavryushin N.K. Cosmological treatise of the 15th century as a monument of ancient Russian natural sciences // Monuments of science and technology . 1981. M .: Nauka, 1981, S. 183—197.
• Lauren Graham Chapter XII Cosmology and Cosmogony from the book Natural History, Philosophy and the Science of Human Behavior in the Soviet Union
• Zhitomirsky S.V. The heliocentric hypothesis of Aristarchus of Samos and ancient cosmology. // Historical and astronomical research. M., 1986. Issue. 18.P. 151-160.
• Idlis G.M. Revolutions in astronomy, physics and cosmology. M., 1985.-232 p.
• Koyre A. From a closed world to an infinite universe. - 2001 ..
• Cosmological works in the book of Ancient Russia. Part II: Texts of plane-mosquito and other cosmological traditions "// Series" Monuments of Old Russian Thought ". Issue IV (2) / Ed. Ed .: VV Milkov, S. M. Polyansky. St. Petersburg: Publishing House . house "Mir", 2008 (640 p. (50B7 a.s.).
• Lebedev A.V. Thales and Xenophanes (Ancient fixation of Thales cosmology) // Ancient philosophy in the interpretation of bourgeois philosophers. M., 1981.
• Lupandin I.V. Aristotelian cosmology and Thomas Aquinas // Questions of the history of natural science and technology . 1989. No. 2. S. 64-73.
• Makeev V.A. Ancient philosophical cosmography in the modern culture of the East. -M .: RUDN, 1993
• Mochalova I. N. About two cosmological traditions in the Early Academy // Bulletin of the A.S. Pushkin Leningrad State University (philosophy series). 2007.- No. 3 (6) .- P.26-34.
• Nagirner D.I. Elements of cosmology. - St. Petersburg: Publishing House of St. Petersburg State University, 2001.
• Pavlenko A.N. Modern cosmology: the problem of justification // Astronomy and the scientific picture of the world. M. IFRAN, 1996;
• Pavlenko A. N. European cosmology: foundations of an epistemological turn, M.- INTRADA, 1997;
• Sazhin M.V. Modern cosmology in a popular presentation. URSS 2002.240 s
• Semushkin A.V. The speculative cult of the cosmos in early Greek philosophy // Religion in a changing world. - M.: Publishing House of RUDN, 1994. - P.27-39.
• Tursunov A. Philosophy and modern cosmology. M., 1977.
• M. L. Filchenkov, S. V. Kopylov, V. S. Evdokimov General Physics Course: additional chapters.
• Frolov B. Number in archaic cosmology // Astronomy of ancient societies. M., 2002.S. 61-68.
• Chernin A.D. Stars and Physics. Vol. 2. URSS 2004.176 p.
• Lawrence Krauss . Why do we exist. The greatest story ever told = Krauss. The Greatest Story Ever Told - So Far: Why Are We Here ?. - M .: Alpina Non-fiction, 2018 .-- ISBN 978-5-91671-948-2 .

• Site about modern cosmology // modcos.com
• Klimushkin D. Yu. Cosmology
• Ned Wright's Cosmology Tutorial (Neopr.) . Archived on August 25, 2011. (eng.)
• Cosmology and Theology (neopr.) . Archived March 15, 2013.
• Publication of the authors of the WMAP project
• What WMAP measured // Astronet
• A. Levin. The Ulysses mission is completed, but the journey continues. // "Elements"