On Thu, Feb 13, 2014 at 1:39 PM, Jesse Mazer <[email protected]> wrote:
> > > On Thu, Feb 13, 2014 at 12:55 PM, Edgar L. Owen <[email protected]> wrote: > >> Jesse, >> >> See my proximate response to Liz who asked the same question. Basically >> relativity theory gives you the equations for both frames for any >> relativistic situation. So all you have to do is do the calculations like >> I've explained to you with nearly a dozen examples. >> >> To the question in your last paragraph. Yes, of course we assume >> originally synchronized clocks. Remember this is a thought experiment, and >> that is clearly possible if we assume it's done at rest relative to each >> other and then magically without acceleration (your instantaneous >> acceleration, which is also physically impossible, but has the exact same >> thought effect). >> >> So do you agree that given synchronized clocks, A and B in relative >> motion will still have synchronized clocks in their own frames to each >> other? I.e., that A will have the same reading on his own clock that B does >> on his own clock? >> > > "Same reading" using what definition of simultaneity? If you're talking > about p-time simultaneity, then I don't agree, because I don't believe in > p-time in the first place. If you're talking about the "same reading" using > the definition of simultaneity assumed in each one's own rest frame, then I > still don't agree. Say that two observers Alice and Bob have their clocks > set to zero when they are at the same point in spacetime (i.e. if I use A > to represent the event of Alice's clock reading 0, and B to represent the > event of Bob's clock reading 0, then all frames will assign exactly the > same space and time coordinates to B that they assign to A), and from that > meeting at a common spatial location they move away from each other > inertially at 0.6c, so in each one's frame the other has a time dilation > factor of sqrt(1 - 0.6^2) = 0.8. Then in Alice's rest frame, the event of > her clock reading 25 would be simultaneous with the event of Bob's clock > reading 20. In Bob's rest frame, the event of his clock reading 25 would be > simultaneous with the event of Alice's clock reading 20 (and in his frame > the event of his clock reading 20 would be simultaneous with the event of > Alice's clock reading 16). Do you disagree with these conclusions about > frame-dependent simultaneity in SR? > > > >> >> And do you also agree that when the relative motion magically stops, >> their clocks will still read the same as each other's, AND they will both >> be the same age because of that? >> > > No, I don't agree. Using the numbers above, if Bob instantaneously > accelerates to come to rest relative to Alice when his clock reads 20, then > he will now be at rest in Alice's rest frame, and it'll still be true in > this frame that the event of Alice's clock reading 25 is simultaneous with > Bob's clock reading 20. Likewise, if Alice instantaneously accelerates to > come to rest relative to Bob when her clock reads 20, she will now be at > rest in Bob's rest frame, and it'll still be true in this frame that the > event of Bob's clock reading 25 is simultaneous with Alice's clock reading > 20. Do you disagree with these conclusions? > How can Bob age 5 years because Alice instantly accelerated into his rest frame? I do not agree. > > >> >> This is just elementary relativity theory, nothing to do with p-time at >> all... >> > > Yes, it is elementary, and if you disagree with any of my statements about > SR above then you need to go back and learn the basics of how SR math > actually works. > > Jesse > > -- > 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. > -- 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.
