AST 101 Lecture Notes - Lecture 7: Nanosecond, Absoluteness, Time Dilation

• School: Stony Brook University
• Department: Astronomy
• Course: AST 101
• Professor: Jin Koda

Document Summary

Usual notions of space and time must be revised for speeds approaching light speed (c) Expands the ideas of special theory to include a surprising new view of gravity. The laws of nature are the same for everyone. The speed of light is the same for everyone. All of relativity follows from these two ideas! If you observe something moving near light speed: Motion can be defined with respect to a particular frame of reference. Einstein claimed that light should move at exactly c in all reference frames (now experimentally verified) Suppose you tried to catch up to your headlight beams. You"d always see them moving away at speed c. Anyone else would also see the light moving ahead of you. Thinking about the motion of a ball on a train will prepare us for the next thought experiment. Someone outside the train would see the ball travel a longer path in one up-down cycle.