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Explain me this.

In twin paradox, one of two twins, paul and peter, when paul goes for a space ride at very high speeds, and peter stays back at earth, when paul comes back, peter is older than him, and paul is still younger because of assymetric aging, also called time dilation.

In detail, when paul starts journey, he accelerates, and his aging process (or clock) slows down. When he travels with a constant speed, his aging process slows down. when he accelerates again to reduce his speed, his aging process slows down. He starts his backword journey again in same manner and his aging slows down. And as there is no time contraction, but only time dilation, an irreversible process, at the end he has aged slowly, and thus, is younger than peter. I agree to that.

Does this same happen with length contraction? I mean, instead of paul and peter, If there would have been two rods L1 and L2, and L1 would have been sent for a space travel, at each step its length would contract, as was the case with time dilation in the case of paul. When the rod comes back to earth, would that rod L1 measure less than road L2?

Only conseptual explanation, no math please...

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# Twin (rod) paradox

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