Cosmology, from the Greek: κοσμολογία (cosmologia, κόσμος (cosmos) world + λογια (logia) discourse) is the study of the Universe in its totality and by extension man's place in it. Though the word cosmology is recent (first used in 1730 in Christian Wolff's Cosmologia Generalis), the study of the Universe has a long history involving science, philosophy, esotericism, and religion.


Disciplines

The earliest form of cosmology appears in the origin beliefs of many religions as they seek to explain the existence and nature of the world. In many 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 and his relationship to one or more divine beings.

In recent times, physics and astrophysics have come to play a central role in shaping what is now known as physical cosmology, i.e. the understanding of the Universe through scientific observation and experiment. This discipline, which focuses on the Universe as it exists on the largest scales and at the earliest times, begins by arguing for the Big Bang model, a sort of cosmic explosion from which the Universe itself is said to have erupted ~13.7 ± 0.2 billion (109) years ago. After its violent beginnings and until its very end, scientists then propose that the entire history of the Universe has been an orderly progression governed by physical laws.

In between the doctrines of religion and science, stand the philosophical perspective of metaphysical cosmology. This ancient field of study seeks to draw logical conclusions about the nature of the Universe, man, god and/or their connections based on the extension of some set of presumed facts borrowed from religion and/or observation. One example is the cosmological argument which is an argument for the existence of God based primarily on the point of view that the mere existence of a universe demands a creator. However, recent work on string theory suggests a megaverse where about 10500 models exist. "If every type of universe exists, there is no need to invoke God (or an unknown master theory of physics) to explain why one of them ended up like ours."

As a finer distinction between religion and philosophy, esoteric cosmology is distinguished from religion in its more sophisticated construction and reliance on intellectual understanding rather than faith, and from philosophy in its emphasis on techniques of psycho-spiritual transformation.


Religious cosmology

Many world religions have origins beliefs 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 (e.g. argument for the existence of God). In the vast majority of origin beliefs, the Universe was created by a direct act of a god or gods who are also responsible for the creation of man. As a conscious creation, the Universe is usually assumed to be endowed by its creator with some purpose or design, aspects of which are often used to frame man's role in the world and his relationship with God. In many cases, religious cosmologies also foretell the end of the Universe, either through another divine act or as part of the original design.

Buddhism, Hinduism 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.

Both Christianity and Judaism accept creation according to Genesis, although the Roman Catholic Church recognizes evolutionary debates, as long as God is recognized as the driving force behind Evolution. 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.


Physical cosmology

Physical cosmology is the branch of physics and astrophysics that deals with the study of the physical origins of the Universe and 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, 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 Tycho Brahe, 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 may be considered to begin in 1915 with Albert Einstein's publication of his general theory of relativity and the growing ability of astronomers to study very distant objects. Prior to this, physicists had assumed that the Universe was static and unchanging. However, the general theory of relativity was not amenable to a static Universe. Thus the Big Bang theory was proposed by the Belgian priest Georges Lemaître in 1927 and rapidly confirmed 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.

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

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 origin of the Universe? What is its first cause? Is its existence necessary?
What are the ultimate material components of the Universe?
What is the ultimate reason for the existence of the Universe? Does the cosmos have a purpose?


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 sometimes difficult to distinguish where religion or philosophy end and esotericism or occultism begins. However, esoteric cosmology is distinguished from religion in its more sophisticated construction and reliance on intellectual understanding rather than faith, and from philosophy in its emphasis on techniques of psycho-spiritual transformation. 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 Gnosticism, Tantra (especially Kashmir Shaivism), Kabbalah, Sufism, Surat Shabda Yoga, Theosophy, Anthroposophy, the Fourth Way teaching of Gurdjieff and Ouspensky, the teachings of Patrizia Norelli-Bachelet, Gnostic circle and in The Rosicrucian Cosmo-Conception (book).