Re: TOM ROBERTS - Dono is confused, please help him out (was SR cannot determine Contraction)

"Dono" <sa_ge@xxxxxxxxxxx> wrote in message news:b7ee185f-8c95-40b3-8da1-
That's too bad, really. I was looking forward to your supporting your
PoV with a paper from before the 1980's ( :-)) (if I understood
correctly).
I am really interested in the resolution of this "stressless length
contraction" , Tom is the last hope, I guess :-)

There is nothing to resolve, as there is no stress involved The proper length of the rod itself (meaning in its own frame of reference) is unchanged. Length contraction is a geometric projection from 4D space-time to the 3D space of a particular frame of reference .. it does not physically change what is being projected from (ie the rod) .. but the projection itself does take up less space (ie it is shorter in length). So (the projection of) the rod fits within the barn.

I suggest you actually read the wiki page link you referred to ( http://en.wikipedia.org/wiki/Length_contraction#A_trigonometric_effect.3F ) and the paper by Janssen. Indeed, read any and all papers and texts on SR to see that your position is incorrect. Length contraction is a real effect in the observers frame .. the contracted object takes up less space at a given time, its length is shorter and so something with a longer proper length can indeed fit within a shorter object (like a pole in a barn). This is what SR predicts .. there really is nothing to argue about here .. if you say length contraction does not happen, then you are saying SR is wrong. It is not a matter of an interpretation.


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Relevant Pages

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