On Sat, Feb 22, 2014 at 8:19 AM, Roarty, Francis X < francis.x.roa...@lmco.com> wrote:
> I don't see why the "direction" of the 2 friends matter > When it comes to the ability to observe the rate of time the other party is experiencing it is everything. If one friend sees the other as receding, this motion will change each friends view of the time rate of the other, they will appear even more slowed than you would have SR predict. (constantly increasing communication delay) If they were travelling toward each other, this motion would make each see the others rate of time faster than it s actually occuring as each moment the communication delay would be less. If they are passing and perpendicular, then they both have a chance to see how time passes in the other frame relative to their own frame without these distortions. It is now harder to imagine that each is going to see time stalled for the other while they are passing through time, this is taken to extremes (which require some variations) we could have centuries pass for each while observing the other to have no time pass. If while passing the friends suddenly accelerate/decelerate equally to come to a relative stop in an arbitrarily short period of time then the experience of each friend is equal (especially if each was the native to their previous reference frames) and one can't be selected to have objectively experienced less time than the other, so it is a draw, each must see time onboard the other guys ship to suddenly speed up supernaturally as they decelerate so that the other twin has had as much time pass as they have had. Worse yet, this speed up would magically depend on how much time needs to be made up for, if both were natives to their respective initial reference frames then they and the matter they are composed on has a LOT of missing time to make up for! But if they are newer to the reference frame which they are now decelerating from, you would expect less time to pass. , dialation is an effect of the velocity wrt C ... no vector is involved, > just a trigonmetric relationship of the spatial plane to another > dimensional axis. > Saying it like that separates it from reality suddenly you can ignore what one sees of another. It is just math, and things can be done that are physically impossible. > Bothfriends slow down the same amount regardless of direction and the > only dilation is between themselves and the outside stationary world they > are passing thru if they have the same velocity.. when they meet up they > should however find their time quite different from that read on a clock at > their stationary meeting place. > The 'stationary' meeting place is moving to. And as such they see the time on this 'stationary' frame to be stopped, even though if they come to a stop relative to this frame, this frame should suddenly be ahead. Secondly the expectation of which twin is far ahead in time depends on how they meet, if one accelerates suddenly to the speed on the other, in that moment it is finally asymmetric and one twin is suddenly old and the other young, if the other twin accelerates it is the reverse. Or they could met in the middle and be the same age, just imagine them face to face at 99% of *C* passing each other and getting to each make that decision that either of then could be young, aged or middle aged in an instant! Yes, SR makes so much sense and is internally consistent. > > > *From:* H Veeder [mailto:hveeder...@gmail.com] > *Sent:* Friday, February 21, 2014 2:06 PM > *To:* vortex-l@eskimo.com > *Subject:* EXTERNAL: Re: [Vo]:Time Dilation impossibility > > > > > > > > On Wed, Feb 19, 2014 at 9:50 PM, Eric Walker <eric.wal...@gmail.com> > wrote: > > On Wed, Feb 19, 2014 at 3:25 PM, H Veeder <hveeder...@gmail.com> wrote: > > > > Imagine two friends with synchronized watches. One friend boards a train > and zips away for a time at near c and then gets off and walks back to his > friend > > so that they can compare the time on their watches. Which watch is ahead? > > > > Using the principles of SR I can come up with contradictory answers. > > > > I'm curious what the two scenarios are. > > > > Eric > > > > > > > > Each friend should see the other's watch tick more slowly according to > special relativity. Therefore when they meet up again, both watches should > record the same elapsed time, but what happened to the time-dilation effect > on the passage time? SR ends in contradiction when watches are compared > after the travelling. > > > > Dave mentions that acceleration might play role in resolving the > contradiction. I have heard that reason too, but it strikes me as hand > waving. Even if acceleration has to be factored in, the ratio of time spent > accelerating to the time spent travelling at uniform speed near c can be > assumed to be arbrarily small so that the acceleration becomes irrelevant. > > > > Harry > > > >
