I’m wondering if it’s mathematically permissible, if space is homogeneous and isotropic, for a moving rod to experience a uniform expansion or contraction during the time it’s not in its stationary frame of reference. What’s preventing a moving rod from returning to its point of origin smaller or larger? The expanding or shrinking effect could go like f(v)exp(kt) for as long as the rod maintains a constant velocity v. Conceivably, this might be made to work in 3 spatial dimensions. Every observer could say that every other frame is shrinking uniformly in time and, akin to the twin paradox, all returning twins could end up YOUNGER and smaller.(adsbygoogle = window.adsbygoogle || []).push({});

Can you prove that homogeneity and isotropy alone disallows this possibility?

Eugene Shubert

http://www.everythingimportant.org/relativity/generalized.htm

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# The Implications of Homogeneity and Isotropy

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