If galaxies travel faster than light because of the expansion of the universe, does this mean that one day we will be able to figure out how to do it too?

I can't imagine how. The apparent faster than light motion we infer for the most distant quasars due to the geometry of the expansion of the universe at earlier times, does not represent the actual motion of these galaxies through the intervening space, but the dilation of 'space itself'. However, a space craft needs to travel across each and every one of the light years that separate Earth from the distant object. This cannot be done faster than light unless you play around with worm holes or other exotica. The cosmological effect is kind of like what happens to a search light beacon as it scans across the sky. At a distance of millions of miles, the geometric tip of the beacon is traveling faster than light, but the slow photons are constantly left behind, and there is no way you can use the tip of the search light to sent information.


Copyright 1997 Dr. Sten Odenwald
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