A and B are twins,A notice B moving away from him with velocity v

IPhO' 2008

A and B are twins,A notice B moving away from him with velocity v, so A notice that B is youngerv than him (time dilation) , In the same way, B notice that A is younger than him.
What happen?

jtbell

Search this forum for "twin paradox." There have been many discussions of this. In fact, there's one going on right now, with the title "Need help understanding the twins."

Hans de Vries

Image 4.26 in section 4.15 (Reversal of Time dilation) explains this all:

http://physics-quest.org/Book_Chapte...multaneity.pdf


Regards, Hans

HallsofIvy

Actually, in this case, nothing is happening! Both are completely correct. Each sees the other as being younger than himself. This only becomes a "paradox" when the two twins are back in the same "frame of reference" (i.e. at rest relative to one another) together again. And that requires acceleration of one of the twins.