The cosmos mean the Universe. When using the word cosmos rather than universe implies to view the universe as a complex and orderly system that serves the opposite of chaos.
Studying cosmology can lead to the understanding of the reasons for its significance and existence. It covers a broad area of religious, scientific, philosophical contemplation of cosmos nature and the reason for its existence.
Philosophical and religious approaches have the concepts of cosmos depicting various spiritual entities that are deemed to exist out of our physical universe.
Physical cosmology ~
Physical cosmology is a scientific study of the universe right from the beginning of its physical existence. It has speculative concepts like multiverse.
Physical cosmology refers to a specific spacetime continuum within a multiverse. This specific cosmos, the observable universe is capitalised as the Cosmos. The uncapitalized term cosmic is subject to the relationship with the universe as 'cosmic time'.
Cosmic rays are high energy particles or radiations of space. The cosmic microwave background is the microwave radiation detected from all directions of space.
Philosophical cosmology ~
Cosmology is the branch of metaphysics dealing with the nature of the universe, a theory that describes the natural order of the universe.
Cosmology is the science of the origin and the development of the universe. In modern astronomy terms, the Big bang theory has been the dominant postulation.
The philosophy of cosmology directs the conceptual foundations of cosmology and philosophical contemplation of the total universe. It exhibits the fundamental theories of physics like quantum mechanics, thermodynamics, statistical mechanics, quantum field theory and general relativity.
Religious cosmology ~
According to theology, the cosmos are the created heavenly bodies like the moon, wandering stars, sun and fixed stars. The concept of the cosmos as the created universe and its arrangement has been used in New Testament over 180 times, due to its importance in Christendom.
The Christian theology uses aion referring to "this world", " worldly life", "this age". Though aion is used for other-worldly sense like the eternal plane of divine.
Knowing The Cosmos...
Having the quest to understand the ways universe works could start with the study of basic building blocks of our existence - space,matter, energy and time - and their behaviour under extreme physical conditions characterizing infant and evolving Universe.
The program on the Physics of the Cosmos (PCOS) includes high-energy astrophysics, cosmology and fundamental physics projects to address the nature of complex astrophysical phenomena like dark energy, black holes, neutron stars, and gravitational waves.
Using the fleet of space-based missions operating on the whole electromagnetic spectrum, PCOS has an overarching goal to learn the origin and destiny of the cosmos.