Relativity Principle #1

But hold on a second! After 4 seconds, isn’t the runner twice as close to where the light beam is as the stationary observer? How could he get the same answer when measuring the speed of light?
- Three possibilities… Either the moving observer doesn’t think that 4 seconds have gone by, or he thinks the light beam is farther away than we perceive it as being, or both….

But hold on a second! After 4 seconds, isn’t the runner twice as close to where the light beam is as the stationary observer? How could he get the same answer when measuring the speed of light?