Relativity




 * Most confusion about relativity centers around a poor understanding of relativity of simultaneity.


 * Since the length of an object is the distance from head to tail at one simultaneous moment, it follows that if two observers disagree about what events are simultaneous then they will also disagree on the length of objects.


 * If a line of clocks appear synchronized to a stationary observer and appear to be out of sync to that same observer after accelerating to a certain velocity then it follows that during the acceleration the clocks ran at different speeds. Some may even run backwards. This line of reasoning leads to general relativity.


 * The gravitational time dilation at any point in a gravity well is equal to the time dilation that an object falling to that point would experience due its velocity (which never reaches "c") alone.

There might be a loophole to the law that you can't travel faster than light: If the distance between the front of rocket and the back can be made zero then it's conceivable that it could travel faster than light.