ASTR 1020 Chapter Notes - Chapter 22: Cosmic Microwave Background, Observable Universe, Planck Units
25 Apr 2017
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Document Summary
Everything began as a hot and dense collection of matter and radiation. It was so hot that photons could transform themselves into matter and vice versa. There were reactions that created and annihilated particles. Electromagnetic force - depends on electrical charge of particle rather than mass. The strong force - operates on extremely short distances. The weak force - operates on extremely short distances. Plays role in nuclear reactions like fusion and fission. Only force besides gravity that affects weakly interacting particles like neutrinos. In early universe, the forces were not as distinct as they are today. Ex: electroweak force, electroweak + strong force = the gut force, or possibly all the forces could"ve combined into one super force . Times before the universe was 10 43 second old. We don"t have a theory to describe conditions in this era. Merger of strong, weak, and electromagnetic force at temps above1029.
