Physics 197 Lecture 29: The Metric Equation

• School: WUSTL
• Department: Physics
• Course: Physics 197
• Professor: Ferrar

Document Summary

Proper time measure the time between the events by a single clock that moves between the events so that it is present at both. There is only one worldline that takes a clock from one event to the other at a constant velocity. Spacetime interval: the proper time between the events measured by an inertial clock is thus a unique, frame-independent number that depends on the spacetime separation of the two events. The speed of light is 1 second of distance per 1 second of time. If there are two reference frames in relative motion along a given line, any displacement measured perpendicular to that direction of motion must have the same value in both reference frames. Muons: subatomic particles that decay with characteristic half-life of 1. 52 x 10^-6 seconds as measured in their rest frame: this is as if they had an internal clock telling them when to decay.