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## Inflation of the Universe.

 Quote by N3Wparadigm Therefore the speed of light isn't a universal speed limit as inflation demonstrates.
You are applying special relativity to a case where it has no business. Both observers A and B are both locally at rest -- they are at rest with respect to the expansion. It is the space itself that is doing the expanding, "carrying" observers A and B along with it. There is no violation of special relativity (which holds only locally).

(I see Mark has already just replied...)

 Quote by Mark M No. As I said in the second post, and as Flustered also stated, relativity places a limit on the velocity of objects moving through spacetime. The recession of galaxies is due to the expansion of the universe, e.g. space being created in between all of the galaxies. It's as if I owned a river, and placed a speed limit of boats in this river at 50 mph, and kept track of their speed using the boats speedometer. A boat could be traveling down the river at 40 mph, but if the river is flowing at 30 mph, its total velocity is 70 mph. But since 30 mph is due to the flowing of the river itself, my speed limit is maintained. Similarly, galaxies dragged along by the expansion of space faster than light do not violate special relativity.
.... but if it were your goal to try and achieve 70mph in your boat to an observer on the river bank, you would use this river as a means of achieving it.

I don't understand how using the expansion of space itself is "cheating" with regard to breaking the speed of light limit, relativity still stands, if you were an observer at point (A) you would see point (B) move away at faster than light speeds, surely how this happens is irrelevant, just by very quickly placing more space between you and point (B) its the same for relativity as saying (A) is moving away from (B) the same as (B) is moving away from (A)

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 Quote by N3Wparadigm .... but if it were your goal to try and achieve 70mph in your boat to an observer on the river bank, you would use this river as a means of achieving it.
THAT part of the anaology is why it is ONLY an analogy. You cannot "use" the expansion of the universe in the same fashion.

 I don't understand how using the expansion of space itself is "cheating" with regard to breaking the speed of light limit, relativity still stands, if you were an observer at point (A) you would see point (B) move away at faster than light speeds,
yes, that it exactly what happens

 surely how this happens is irrelevant
no, it is NOT irrelevant. SR places a limit on travel IN space, not travel OF space, if you see what I mean

The river analogy is a good one (but it is ONLY an analogy) in that it IS the boats speedometer that is measured, not the total speed.

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