CEM 141 Lecture 21: CEM 141 10/19 Lecture 21 (Chapter 3: Origins of Atoms)
Document Summary
About 15 billion years ago a tremendous explosion started the expansion of the universe. At the point of this event all of the matter and energy of space was contained at one point. What existed before the big bang is unknown and a matter of speculation. He observed that the universe is continually expanding. He discovered that a galaxy"s velocity is proportional to its distance. Galaxies that are twice as far from us move twice as fast. There"s been more and more distance between clusters of galaxies. This phenomenon of galaxies moving farther away from each other is known as the red shift. There is microwave radiation coming from the farthest outreaches of the universe. 1 picosecond after - no atoms - only leptons (quarks, electrons) Few minutes - h+ d+ he2+ li3+ (density of air) For 400k years temp dropped - no further fusion. *everything in the universe is continually moving away from us at increasing speed.
