That depends.

If you say: he doesn't know about special relativity, then he'd expect to measure a time intervall of 20 seconds, but measures 6.24 seconds. This means what he measures is shorter than expected.

If you say: he knows that c is constant, but is careless, and thus ignores time dilation, THEN he'd measure something that is longer than expected. That, however, is not the true pre-relativistic interpretation.*


Thanks for the links! I'll check them out soonish.



I think we all agreed with Joey (yes, you too :P). The isse was, if I remember correctly (and a quick look through this thread suggests the same), that Joey was referring to the, if you will, "second" part of this paradox - that is to say he explained why you cannot invoke symmetry of the observers NAIVELY (Travelling twin is not at rest in any inertial system for the whole duration of flight, including turning around). He never showed any signs of not understanding this "paradox", I think.
If you disagree, that's fair enough. But could you then, perhaps, state in clear words where exactly you believe our opinions differ?


* That is to ignore the fact that c=constant can be "seen" from the Maxwell-equations, but let us assume our doctor is a medical doctor, and perhaps not so well-versed in the physics