(June 29, 2014 at 3:55 pm)StuW Wrote: 3 points in space A - B - C. B has been moving away from A for 13.8by and C has been moving away from B for 13.8by so why can't the universe be 27.6by in size wyrd? (Its completely innacurate but demonstrates a basic point). Using the same idea, if A was moving away from B at 99.9%c and C was moving away from B at 99.9%c, how fast is A moving away from C? ...199.8%c because relative velocities are not constrained, just absolute velocities. Therefore relative to the space expanding at >c its still less than c in the absolute frame of reference. That's how i understand it anyway.
You're on the right track - one piece that's missing is that it's the underlying space that is expanding. The objects (galaxies, etc) are not moving per se, but rather being "carried" as space itself expands.
Wyrd is confused because he thinks we don't see this effect locally - we do, except where objects are gravitationally bound. The shorter the distance, the greater the gravitational force. The Andromeda galaxy is moving towards us because we are gravitationally bound to it, and are in mutual orbit.
So why isn't the Milky Way "riding the wave" of expanding space and hurtling away from far away galaxies at relativistic speeds. We are. Our frame of reference simply doesn't allow us to observe it.
As I said: Wyrd doesn't understand relativity, and he apparently doesn't care to.
