The Twin Paradox: Mike & Angela's Frame of Reference

[delve]

I am confused about the twin paradox. Let's imagine Mike and Angela are twins. Mike stays on Earth, and Angela rockets off, away from Earth at close to the speed of light, with the intention of making a round trip back to Earth at the end of her voyage. My question is this: why wouldn't Angela see Mike's frame of reference as accelerating and decelerating, just as Mike sees Angela's frame of reference as accelerating and deceleration? Thank you.

 

[DaveC426913]

I am confused about the twin paradox. Let's imagine Mike and Angela are twins. Mike stays on Earth, and Angela rockets off, away from Earth at close to the speed of light, with the intention of making a round trip back to Earth at the end of her voyage. My question is this: why wouldn't Angela see Mike's frame of reference as accelerating and decelerating, just as Mike sees Angela's frame of reference as accelerating and deceleration? Thank you.

Angela feels the force of acceleration twice on her journey. She knows she is not in an inertial frame of reference. That is what breaks the symmetry of the scenario.

 

[ASD16]

it is angela who is accelrating and hence is affected by it...angela's frame is not an inertial frame but an accelerated one...on the other hand...no force is acting on mike...so his frame is an inertial frame...so angela won't see mike's frame as accelerating or decelerating...becoz the force is acting on angela and not on mike...

 

[harrylin]

I am confused about the twin paradox. Let's imagine Mike and Angela are twins. Mike stays on Earth, and Angela rockets off, away from Earth at close to the speed of light, with the intention of making a round trip back to Earth at the end of her voyage. My question is this: why wouldn't Angela see Mike's frame of reference as accelerating and decelerating, just as Mike sees Angela's frame of reference as accelerating and deceleration? Thank you.

That is what they see if they use accelerated reference systems; and nature doesn't care. A change of velocity (as defined with respect to inertial reference systems) breaks the symmetry. That was already elaborated in the first paper on this topic, here (p.47, and on from p.50):
http://en.wikisource.org/wiki/The_Evolution_of_Space_and_Time