[joglynne]

Originally Posted by Chris

I’m getting a headache but only because I don’t know why I’d be able to see B and D but not C, if A, B, C and D are all in a line together

As for point 3, yes, two cars traveling through town at 30mph in opposite directions are increasing the distance between them at a rate of 60mph, but neither car is traveling at 60mph and so neither car is breaking the speed limit.

Likewise, two galaxies traveling in opposite directions at 75% of lightspeed are increasing the distance between them at 1.5x lightspeed, but neither galaxy is actually traveling faster than light and therefore neither of them is breaking the universal speed limit.

If you were an observer located in either one of these galaxies, you would never be able to see the other galaxy because the light emanating from each could never reach the other (the light would have to travel at 1.5x lightspeed in order to do so, and it can’t).

Thanks for your patience Chris and sorry about the headache. I can't see point C as it's apparently everywhere and was using point C as the starting point for the 2 things that are travelling away from each other.

I saw the following video by Brian Cox, explaining cosmic inflation, when it was first aired and since this thread started I have watched it again and keep hoping that one day there will be an explanation that I can comprehend.

https://www.youtube.com/watch?v=BD0r2Xfgh_E