Physics 197 Lecture 33: Nature of Time

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

Document Summary

The coordinate time (cid:791)t between two events is the time measured in the context of an inertial reference frame. Although the radar method does not involve the use of synchronized clocks, it does depend on the assumption that the speed of light is the same in every inertial frame. The coordinate time difference between two events is also frame-dependent using the radar method. The calculations of a distance in any coordinate system should yield the same result if they are valid. Straight line distance is most direct avenue. Pathlength is taking, for example, paths rather than a straight route across grass. In general, the pathlength between two points will depend on the path chosen, and will always be greater than (or at best equal to) the straight-line distance. We can avoid the use of a reference frame if we measure the time interval between these events with a clock that is present at both events.