Cosmology (from
Greek - ,
kosmos, "universe"; and ,
-logia, "study") is the study of the
Universe in its totality, and by extension, humanity's place in it. Though the word
cosmology is recent (first used in 1730 in
Christian Wolff's
Cosmologia Generalis), study of the universe has a long history involving
science,
philosophy,
esotericism, and
religion.
Disciplines
In recent times,
physics and
astrophysics have played a central role in shaping the understanding of the universe through scientific observation and experiment; or what is known as
physical cosmology shaped through both mathematics and observation in the analysis of the whole universe. In other words, in this discipline, which focuses on the universe as it exists on the largest scale and at the earliest moments, it is generally understood to begin with the
big bang (possibly combined with
cosmic inflation) – an
expansion of space from which the universe itself is thought to have emerged ~ (13.7
billion) years ago.
From its violent beginnings and until its various speculative
ends, cosmologists propose that the history of the universe has been governed entirely by
physical laws.
Theories of an impersonal universe governed by physical laws were first proposed by
Roger Bacon, a somewhat persecuted member of the Catholic Church.
Between the domains of
religion and science, stands the
philosophical perspective of
metaphysical cosmology. This ancient field of study seeks to draw
intuitive conclusions about the nature of the universe, man, God and/or their relationships based on the extension of some set of presumed facts borrowed from spiritual experience and/or observation.
But metaphysical cosmology has also been observed as the placing of man in the universe in relationship to all other entities. This is demonstrated by the observation made by
Marcus Aurelius of a man's place in that relationship: "He who does not know what the world is does not know where he is, and he who does not know for what purpose the world exists, does not know who he is, nor what the world is." This is the purpose of the ancient metaphysical cosmology. However,
Stoicism rejected Aristotle's theory of universals as being "in the things themselves," calling them "figments of the mind."
Stanford Encyclopedia of Philosophy adopting the concept of universals as being "concepts," and therefore of the mind, and therefore controllable by free will. Thus, we get the analysis of Aurelius' that the nature of the universe is not from "intuition," but from a free-will, conceptual understanding of the nature of the universe.
Cosmology is often an important aspect of the
creation myths of
religions that seek to explain the
existence and nature of
reality. In some cases, views about the creation (
cosmogony) and destruction (
eschatology) of the universe play a central role in shaping a framework of
religious cosmology for understanding humanity's role in the universe.
A more contemporary distinction between religion and philosophy,
esoteric cosmology is distinguished from religion in its less tradition-bound construction and reliance on modern "intellectual understanding" rather than
faith, and from philosophy in its emphasis on
spirituality as a formative concept.
There are many historical cosmologies:
"… the universe itself acts on us as a random, inefficient, and yet in the long run effective, teaching machine. …our way of looking at the universe has gradually evolved through a natural selection of ideas." —Steven Weinberg
Historical cosmologies
The following table outlines the significant historical cosmologies in chronological order.
Historical descriptions of the cosmos
Table Notes: the term "static" simply means not expanding and not contracting. Symbol G represents Newton's
gravitational constant; Λ (Lambda) is the
cosmological constant.
Physical cosmology
Physical cosmology is the branch of physics and astrophysics that deals with the study of the physical origins and evolution of the Universe. It also includes the study of the nature of the Universe on its very largest scales. In its earliest form it was what is now known as
celestial mechanics, the study of the
heavens. The Greek philosophers
Aristarchus of Samos,
Aristotle and
Ptolemy proposed different cosmological theories. In particular, the
geocentric Ptolemaic system was the accepted theory to explain the motion of the heavens until
Nicolaus Copernicus, and subsequently
Johannes Kepler and
Galileo Galilei proposed a
heliocentric system in the 16th century. This is known as one of the most famous examples of
epistemological rupture in physical cosmology.
With
Isaac Newton and the 1687 publication of
Principia Mathematica, the problem of the motion of the heavens was finally solved. Newton provided a physical mechanism for
Kepler's laws and his
law of universal gravitation allowed the anomalies in previous systems, caused by gravitational interaction between the planets, to be resolved. A fundamental difference between Newton's cosmology and those preceding it was the
Copernican principle that the bodies on earth obey the same
physical laws as all the celestial bodies. This was a crucial philosophical advance in physical cosmology.
Modern scientific cosmology is usually considered to have begun in 1917 with
Albert Einstein's publication of his final modification of
general relativity in the paper "Cosmological Considerations of the General Theory of Relativity," (although this paper was not widely available outside of Germany until the end of
World War I). General relativity prompted
cosmogonists such as
Willem de Sitter,
Karl Schwarzschild and
Arthur Eddington to explore the astronomical consequences of the theory, which enhanced the growing ability of
astronomers to study very distant objects. Prior to this (and for some time afterwards), physicists assumed that the Universe was static and unchanging. In parallel to this dynamic approach to cosmology, a debate was unfolding regarding the nature of the cosmos itself. On the one hand, Mount Wilson astronomer
Harlow Shapley championed the model of a cosmos made up of the
Milky Way star system only.
Heber D. Curtis, on the other hand, suggested spiral nebulae were star systems in their own right, island universes. This difference of ideas came to a climax with the organization of the
Great Debate at the meeting of the (US) National Academy of Sciences in Washington on 26 April 1920. The resolution of the debate on the structure of the cosmos came with the detection of novae in the
Andromeda galaxy by
Edwin Hubble in 1923 and 1924. Their distance established spiral nebulae well beyond the edge of the Milky Way and has galaxies of their own. Subsequent modeling of the universe explored the possibility that the
cosmological constant introduced by Einstein in his 1917 paper may result in an
expanding universe, depending on its value. Thus the
big bang theory was proposed by the
Belgian priest
Georges Lemaître in 1927 which was subsequently corroborated by
Edwin Hubble's discovery of the
red shift in 1929 and later by the discovery of the
cosmic microwave background radiation by
Arno Penzias and
Robert Woodrow Wilson in 1964. These findings were a first step to rule out some of many
alternative physical cosmologies.
Recent observations made by the
COBE and
WMAP satellites observing this background radiation have effectively, in many scientists' eyes, transformed cosmology from a highly speculative science into a predictive science, as these observations matched predictions made by a theory called
Cosmic inflation, which is a modification of the standard
big bang theory. This has led many to refer to modern times as the "Golden age of cosmology."
Metaphysical cosmology
thumb|right|320px|[[Hand-colouring|Hand-coloured version of the anonymous wood engraving known as the
Flammarion woodcut(1888).]]
In
philosophy and
metaphysics, cosmology deals with the world as the totality of space, time and all phenomena. Historically, it has had quite a broad scope, and in many cases was founded in religion. The ancient Greeks did not draw a distinction between this use and their model for the cosmos. However, in modern use it addresses questions about the Universe which are beyond the scope of science. It is distinguished from religious cosmology in that it approaches these questions using philosophical methods (e.g.
dialectics). Modern metaphysical cosmology tries to address questions such as:
- What is the ultimate reason for the existence of the Universe? Does the cosmos have a purpose? (see teleology)
Religious cosmology
Many world
religions have
creation myths that explain the beginnings of the Universe and life. Often these are derived from
scriptural teachings and held to be part of the faith's
dogma, but in some cases these are also extended through the use of philosophical and metaphysical arguments.
In some creation myths, the universe was
created by a direct act of a
god or gods who are also responsible for the creation of
humanity (see
creationism). In many cases, religious cosmologies also foretell the
end of the Universe, either through another divine act or as part of the original design.
240px|thumb|Large scale structure of the Universe according to one Hindu cosmology.
- Certain adherents of Buddhism, Hinduism (See also Hindu cosmology) and Jainism believe that the Universe passes through endless cycles of creation and destruction, each cycle lasting for trillions of years (e.g. 331 trillion years, or the life-span of Brahma, according to Hinduism), and each cycle with sub-cycles of local creation and destruction (e.g. 4.32 billion years, or a day of Brahma, according to Hinduism). The Vedic (Hindu) view of the world sees one true divine principle self-projecting as the divine word, 'birthing' the cosmos that we know from the monistic Hiranyagarbha or Golden Womb.
- A complex mixture of native Vedic gods, spirits, and demons, overlaid with imported Hindu and Buddhist deities, beliefs, and practices are the key to the Sri Lankan cosmology.
- The Australian Aboriginal concept of Dreaming explains the creation of the universe as an eternal continuum; everywhen. Through certain ceremonies, the past "opens up" and comes into the present. Each topographical feature is a manifestation of dormant creation spirits; each individual has personal Dreamings and ceremonial responsibilities to look after the spirits/land, determined at birth, within this belief framework.
Many religions accept the findings of physical cosmology, in particular the
Big Bang, and some, such as the
Roman Catholic Church, have embraced it as suggesting a philosophical first cause. Others have tried to use the methodology of science to advocate for their own religious cosmology, as in
intelligent design or
creationist cosmologies.
Esoteric cosmology
Many
esoteric and
occult teachings involve highly elaborate cosmologies. These constitute a "map" of the Universe and of states of existences and consciousness according to the
worldview of that particular doctrine. Such cosmologies cover many of the same concerns also addressed by religious and philosophical cosmology, such as the origin, purpose, and destiny of the Universe and of
consciousness and the nature of
existence. For this reason it is difficult to distinguish where religion or philosophy end and esotericism and/or occultism begins.
Common themes addressed in esoteric cosmology are
emanation,
involution,
evolution,
epigenesis,
planes of existence, hierarchies of
spiritual beings, cosmic cycles (e.g.,
cosmic year,
Yuga),
yogic or spiritual disciplines, and references to
altered states of consciousness. Examples of esoteric cosmologies can be found in modern
Theosophy,
Gnosticism,
Tantra (especially
Kashmir Shaivism),
Kabbalah, or
Sufism.
See also
