Twin paradox

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JesseM

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As near as I can figure, Born and the others adopted Einstein's 1918 scenerio that attempted to explain the paradox from a dynamic point of view rather than a pure kinematic solution as per SR..
The SR explanation is just as dynamic as the GR explanation, the only difference is that the SR explanation calculates the dynamics in inertial frames only, while the GR explanation calculates the dynamics in the non-inertial frame of the accelerating twin.
yogi said:
for example in the common explanation that is based upon the shift in the lines of simultaneity
No it isn't. The most common explanation is just to point out that from any single inertial frame you will be able to calculate the elapsed time on each clock; what you are talking about is comparing simultaneity in the inertial rest frame where the twin is at rest in the outbound leg with simultaneity in the inertial rest frame where the twin is at rest on the inbound leg, but if you're trying to sneak in some notion about a simultaneity shift "from the perspective" of the twin who accelerates, then you're implicitly using a non-inertial frame, and the standard equations of SR cannot be used in this frame.
yogi said:
the so called missing time is graphically apparent - but there is no physics per se.
There is no "missing time" in the SR explanation which involves only inertial frames. Again, you seem to be trying to figure out what things look like from the perspective of the accelerating twin, but this is outside of the domain of the standard "SR resolution" of the twin paradox.
yogi said:
I will not discuss this further, as my only interest was to show that reasonable people having sound scientific backgrounds can differ about whether SR adequately explains the clock paradox
No, no one with a "sound scientific background" believes that SR fails to resolve the twin paradox. All you have shown is that various scientists think GR is necessary to analyze the twin paradox from the perspective of the accelerating twin, but you have not shown a single quote where any scientist says that the twin paradox cannot be adequately resolved from the perspective of an inertial frame, and I am confident you never will.

The problem here is that, as always, you seem unable to distinguish between frame-dependent statements and objective physical truths. When mainstream physicists analyze things from the frame of the accelerating twin, and find that in this frame the Earth's clock jumps forward rapidly during the acceleration due to a uniform gravitational field, they are not claiming that this is somehow "more correct" than the perspective of an inertial frame in which the Earth's clock ticks at a constant rate and the traveling twin's clock ticks at different rates during the inbound and outbound leg of the trip (unless you're using a frame where the inbound and outbound leg have equal and opposite velocities, in which case the rate of ticking is the same on both legs) and nothing special happens during the acceleration. The ability to analyze things from the perspective of non-inertial frames simply expands the set of possible frames you can use, but it is still true that no one frame's perspective is any more valid than any other's. If you insist on thinking that there must be some "real truth" about the rate each twin's clock ticks at each moment in the trip, and that there can be physical reasons to think one frame's perspective is more likely to represent this truth than any other's, and you quote mainstream physicists out-of-context to make it sound like they agree, then you are a crackpot, plain and simple.
 
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