On 2002-02-21 14:55, SeanF wrote:
On 2002-02-21 14:22, GrapesOfWrath wrote:
No apologies necessary!
I dunno about that. I use three inertial frames when I explain the twins paradox--at least one version anyway--but I note that it could just as well be done with three different observers. Is it still a twins paradox if you have to have three observers?
Hmm . . . the new-and-improved Special Relativity Triplets Paradox! No, actually, that wouldn't work anyway since you'd have disagreement on whether the three observers were born simultaneously.
Any "normal" (whatever that
means!) depiction of the Twins Paradox requires two (and only two) observers, who cross paths with each other twice. This is impossible with only two inertial frames (they'd pass once and then just keep moving apart), so you need at least
(Of course, if the universe actually is analgous to JW's favorite balloon, the observers would eventually come back together from the other side, and . . . okay, that's really
making my head hurt - forget I said it)
So, I guess the three-observer example is not technically
a "Twins Paradox," but it does demonstrate the same time dilation and simultaneity discrepency factors of SR - and it does so without accelerating anything, which is kind of why I feel that acceleration shouldn't be considered a contributing factor in the normal Twins Paradox to begin with.