Summary
Special relativity describes motion of objects at constant velocity.
- Essential for speeds approaching c -- Tested Experimentally
Moving objects appear to have:
- Clocks that run slow (ALL physical processes “run slow”)
- Lengths that contract along the line of motion
The order of events at different places in space can be different for different observers.
Space & time intertwined: 4-dimension “Space-Time”
- c is the conversion factor between time and space
- International standard
Two type of paradoxes
- Car-Garage: Not a paradox. The only difference is how Sue and Joe described the order of events
- Twin: The twin who leaves the earth and returns really is younger! Tested experimentally by accurate clocks and subatomic particles