AST 104 Lecture Notes - Lecture 20: Edwin Hubble, Parsec, Spacetime
Document Summary
Lecture 20: hubble"s law and the expanding universe part 1. Einstein: space and time are linked together as spacetime spacetime is dynamic (changing, not static) Einstein should have predicted the expansion of the universe! In 1915, albert einstein his general theory of relativity. Space and time are not already there as a background on which stuff happens. Instead, space and time are defined by matter"s distribution and motion. General relativity is a very well-tested and validated scientific framework. For example, the general theory of relativity actually predicts that the universe can"t be static. An expanding universe isn"t an explosion into pre-existing empty space. Space, time, and all the matter in the universe all came into being at a particular moment (the start of the expansion). An expanding universe of raisin galaxies in a bread loaf spacetime. Raisin 1 started 1 cm away and ended up 3 cm away.
