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Topic: THE MYSTERY OF THE TWIN PARADOX
Replies: 6   Last Post: Sep 24, 2013 9:45 PM

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Pentcho Valev

Posts: 3,243
Registered: 12/13/04
Re: THE MYSTERY OF THE TWIN PARADOX
Posted: Sep 9, 2013 1:00 AM
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The mystery of mutual length contraction:

As judged from the 40 m barn's frame, the 80 m pole is shorter than 40 m and accordingly the pole is gloriously trapped inside the barn, Divine Einstein, yes we all believe in relativity, relativity, relativity. As judged from the 80 m pole's frame, the 40 m barn is shorter than 20 m but nevertheless the relativity of simultaneity allows the pole to get gloriously trapped inside the barn, Divine Einstein, yes we all believe in relativity, relativity, relativity. Some Einsteinians believe that the 80 m pole is trapped inside the 40 m barn "IN A COMPRESSED STATE":

http://math.ucr.edu/home/baez/physics/Relativity/SR/barn_pole.html
"These are the props. You own a barn, 40m long, with automatic doors at either end, that can be opened and closed simultaneously by a switch. You also have a pole, 80m long, which of course won't fit in the barn. (...) If it does not explode under the strain and it is sufficiently elastic it will come to rest and start to spring back to its natural shape but since it is too big for the barn the other end is now going to crash into the back door and the rod will be trapped IN A COMPRESSED STATE inside the barn."

http://www.parabola.unsw.edu.au/vol35_no1/vol35_no1_2.pdf
"Suppose you want to fit a 20m pole into a 10m barn. (...) Hence in both frames of reference, the pole fits inside the barn (and will presumably shatter when the doors are closed)."

Other Einsteinians agree that the long pole can be trapped inside the short barn but insist that the pole undergoes no compression or structural deformation, Divine Einstein, yes we all believe in relativity, relativity, relativity:

http://alcor.concordia.ca/~scol/seminars/conference/abstracts/Durand.html
Stéphane Durand: "La contraction une longueur est un phénomène à la fois réel mais sans déformation structurelle. C'est un phénomène réel (et non pas une illusion) car, par exemple, une perche dont la longueur au repos est plus grande que la longueur au repos d'une grange peut réellement être contenue dans cette dernière si elle se déplace assez rapidement. Par contre, il ne peut y avoir de contraction structurelle de la perche, i.e de déformation matérielle de l'objet, car la contraction de sa longueur aurait aussi lieu si c'était plutôt l'observateur qui se mettait en mouvement sans changer l'état de mouvement de la perche. Autrement dit, sans changer l'état de la perche, en se mettant soi-même en mouvement, on change sa longueur: ce n'est donc clairement pas une contraction matérielle (l'état de la perche est le même dans les deux cas). De plus, si deux observateurs se mettent en mouvement à des vitesses différentes par rapport à la perche, ces deux observateurs vont mesurer une longueur différente de la même perche. Une situation inexplicable en termes de contraction matérielle de la perche."

http://www.quebecscience.qc.ca/Revolutions
Stéphane Durand: "Ainsi, une fusée de 100 m passant à toute vitesse dans un tunnel de 60 m pourrait être entièrement contenue dans ce tunnel pendant une fraction de seconde, durant laquelle il serait possible de fermer des portes aux deux bouts! La fusée est donc réellement plus courte. Pourtant, il n'y a PAS DE COMPRESSION matérielle ou physique de l'engin."

Any time a long object is gloriously trapped inside a short container, Einsteinians sing "Divine Einstein" and "Yes we all believe in relativity, relativity, relativity". Singing goes on quietly until the ecstasy gets uncontrollable: in the end believers tumble to the floor, start tearing their clothes and go into convulsions:

http://www.haverford.edu/physics/songs/divine.htm
DIVINE EINSTEIN. "No-one's as dee-vine as Albert Einstein not Maxwell, Curie, or Bohr! His fame went glo-bell, he won the Nobel - He should have been given four! No-one's as dee-vine as Albert Einstein, Professor with brains galore! No-one could outshine Professor Einstein! He gave us special relativity, That's always made him a hero to me! No-one's as dee-vine as Albert Einstein, Professor in overdrive!"

http://www.youtube.com/watch?v=5PkLLXhONvQ
We all believe in relativity, relativity, relativity. Yes we all believe in relativity, relativity, relativity. Everything is relative, even simultaneity, and soon Einstein's become a de facto physics deity. 'cos we all believe in relativity, relativity, relativity. We all believe in relativity, relativity, relativity. Yes we all believe in relativity, relativity, relativity.

Pentcho Valev



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