What really is time?

Posers and Puzzles 30 Dec '09 03:05
1. AThousandYoung
No1GaveAF*IWasWhite
13 Jan '10 10:012 edits
Originally posted by smaia
There is no such thing as "absolute" time. Generally, you cannot synchronize clocks based on an "absolute time" and time is relative to the observer.
There is no preferred time frame, but any event's time can be mapped to any arbritrary time frame at a different velocity using the Lorenz factor.

For example, if you sped up to a velocity where time passes half as quickly for you, then you could speed up the clock to twice the speed and it would be synchronized with a stationary clock.

What is relative to the observer is the rate of change of time.
2. 13 Jan '10 16:17
Originally posted by KazetNagorra
In the context of special relativity, "same place" means the same x, y, z coordinates in some inertial frame of reference.
... in some inertial frame of reference? And where do you find something like that?
3. 14 Jan '10 08:23
Originally posted by FabianFnas
... in some inertial frame of reference? And where do you find something like that?
An inertial frame of reference is one in which the laws of physics hold. So you can check it by checking if that is (approximately) true.