Re: GR question
I can barely spell GR but I might can help with this one.
Originally Posted by Tensor
Think of all the coordinates fixed around you and your computer. They are not "moving". This is one inertial frame. A car going down a straight road and at a constant speed is another inertial frame. Rectilinear and fixed speed for you or an object so that all the coordinates in it's space are fixed is an inertial frame. If you drop a ball inside your car, traveling at any fixed speed, the ball will fall downward and you, and others not in the car, will measure all motion nicely. You see the ball go straight down with 0 forward motion. If your car is doing 70 then your ball is doing 70 in the eyes of those standing on the ground in their inertial frame of reference.
There are an infinite number of inertial frames, obviously. Newtonian view held to an absolute inertial frame out there. It wasn't then, and isn't now, necessary to know it in order to calculate relative motions as shown above. I wonder if they thought the ether wind was 0 in this frame?
Of course, special relativity changed the meaining of "measuring motion nicely". We don't have an absolute space but we do have an absolute speed.
We know time flies, we just can't see its wings.