ASTR 121 Lecture Notes - Lecture 10: Gravitational Potential, Gravitational Redshift, Photon
Document Summary
Special relativity shows that space and time absolute. Instead they are inextricably linked in a four dimensional combination called spacetime. Travelers going in opposite directions in a line they will eventually meet. Because they meet the travelers know earth"s cannot be flat. In the presence of a gravitating mass, spacetime curved. Matter distorts spacetime in the same way that weights distort a rubber sheet. A freely falling observer in a gravitational sees the same results of local, short duration experiments as an observer not in a gravitational field. There"s no way to tell between a freely falling frame and a gravitational field inertial. "matter tells spacetime how to curve and time are not a four- in a straight earth"s surface spacetime is way that heavy a gravitational field duration a gravitational falling inertial frame and spacetime. "matter tells spacetime how to curve and tells matter how to move"