The Clock Paradox in Relativity

Abstract

As I have repeatedly pointed out, symmetrical ageing in this problem is an inevitable requirement of the postulate of relativity. I have given tne argument in the simplest possible form¹ in order to facilitate refutation if it is indeed wrong. I therefore find it inexplicable that Sir Charles Darwin², while completely ignoring this argument (in which he is at one with all other critics), can write that “the accepted theory of relativity ċ quite definitely implies that a space-traveller will return from his journey younger than his stay-at-home twin brother”. His reason for this assertion appears to be identical with that of Dr. J. H. Fremlin, on which I have already commented³. Since that comment appears to have been inadequate, I will consider the problem posed in more detail, in order to bring out what I believe to be the misconception underlying such arguments as that of Sir Charles Darwin.