Homogeneous and Isotropic Universe Models

One of the most successful and useful applications of Einstein’s General Theory of Relativity is within the field of cosmology. Newton’s theory of gravitation, involves attraction between celestial bodies. However, very little is said of the evolution of the universe itself. The universe was believed to be static, and its evolution was beyond any physical theory. But after the year 1917, things were different. Within two years after the birth of the General Theory of Relativity, Einstein realized that this theory actually could say something about the universe and constructed a static universemodel as a solution of the relativistic field equations. The era of modern cosmology had begun, which would revolutionize our view of the universe.