For a trip of interstellar distance, the time dilation caused by getting into low earth orbit will be insignificant. Alice and Bob can compare their watches when Alice is in orbit, and see that they are still synchronised to high accuracy, at least as far as humans are concerned - there might be a few nano or even microseconds difference, but that will be nothing compared to the difference that will occur after a trip to another star and back. In fact there are competing effects here, Alice is travelling at several km/s relative to Bob, but experiencing a slightly weaker gravitational field.
Then Alice fires up the TC drive and heads off towards interstellar space at 1g... On 2 February 2014 14:51, meekerdb <[email protected]> wrote: > On 2/1/2014 9:46 AM, John Clark wrote: > > On Sat, Feb 1, 2014 at 7:57 AM, Edgar L. Owen <[email protected]> wrote: > > > One might think it was the acceleration that slowed time on A's clock, >> BUT the point is that A's acceleration was only 1g throughout the entire >> trip which was exactly EQUAL to B's gravitational acceleration back on >> earth. So if the accelerations were exactly equal during the entire trip >> how could A's acceleration slow time but B's not slow time by the same >> amount? >> > > If A were going into space and accelerating upward off the surface of > the Earth at one g (32 feet per second per second), then he would be > experiencing 2g, one g from the Earth and one g from his continuing change > in upward velocity. > > > But A would experience acceleration quickly decreasing to 1g as he left > the vicinity of the Earth. And the result wouldn't change if B entered a > centrifuge and experienced an exactly equal acceleration while remaining on > Earth. This is why I emphasize that it is NOT an effect of acceleration, > it is a geometric effect of different path lengths. > > Brent > > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
