ASTRON 1010 Lecture Notes - Lecture 2: Cosmic Microwave Background, Heinrich Wilhelm Matthias Olbers, Edwin Hubble
Document Summary
Cosmology is the study of the nature and evolution of the universe as a whole. Evidence for the big bang and gaps in our understanding. Cosmic microwave background (cmb): the observed cmb radiation shows that the early universe was very hot and dense, with a uniformity unlike the distribution of mass concentrated into galaxies today. This uniformity is exactly as predicted by the big band theory. Temperature and density fluctuations: the existence of small fluctuations in the cosmic microwave. Background radiation (1 part in 100,000) that would grow into galaxies over the course of a billion years. The fluctuations exactly match what the big bang theory predicts for a universe that started out as a speck. Thus, the entire sky should be bright, as it would be filled with stars. Therefore, this observational fact that the sky is not bright requires the universe to either be finite in size or finite in age.
