What is Cosmology? by Burt Jordaan
The word 'cosmology' originated in Greek: 'cosmologia', meaning order, orderly arrangement or ornaments, plus the word 'logos', meaning word, reason or plan. Cosmology is the study of the Universe at large, which has a long history, involving at least three main regimes: religion, philosophy and science. This article deals mainly with scientific cosmology.

Scientific Cosmology

Also called physical cosmology, it is the branch of science that deals with the scientific study of the origins and evolution of the Universe and the nature of the Universe on its very largest scales.

In its earliest form (2nd century BC) physical cosmology was basically just celestial mechanics, the study of the 'heavens'. The Greek philosophers Aristarchus of Samos, Aristotle and Ptolemy proposed different theories for how the heavens work.

In particular, the 'earth-centric' Ptolemaic system was the accepted theory to explain the mot ... Read more »