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Replies: 2   Last Post: Dec 29, 2012 2:35 AM

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Pentcho Valev

Posts: 6,212
Registered: 12/13/04
Posted: Dec 28, 2012 5:42 AM
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Joao Magueijo, Faster Than the Speed of Light, p. 250: "Lee [Smolin] and I discussed these paradoxes at great length for many months, starting in January 2001. We would meet in cafés in South Kensington or Holland Park to mull over the problem. THE ROOT OF ALL THE EVIL WAS CLEARLY SPECIAL RELATIVITY. All these paradoxes resulted from well known effects such as length contraction, time dilation, or E=mc^2, all basic predictions of special relativity. And all denied the possibility of establishing a well-defined border, common to all observers, capable of containing new quantum gravitational effects."

Special relativity is a deductive construction based on two postulates - the principle of relativity and the principle of constancy of the speed of light - so the falsehood of one of them is the precise "root of all the evil". The troublesome time dilation and length contraction can be deduced DIRECTLY from the second postulate (without employing the principle of relativity):

Accordingly, if Magueijo and Smolin want to get rid of time dilation and length contraction, they will have to declare the second postulate false, which will be equivalent to the following:

The deduction of time dilation and length contraction from the principle of constancy of the speed of light can be presented as REDUCTIO AD ABSURDUM:

Premise: The speed of light is independent of the speed of the light source.

Conclusion 1: The youthfulness of the travelling twin is both due to and independent of his acceleration.

Conclusion 2: Arbitrarily long objects can be trapped inside arbitrarily short containers.
What is wrong with relativity?, G. BURNISTON BROWN, Bulletin of the Institute of Physics and Physical Society, Vol. 18 (March, 1967) pp.71-77: "A more intriguing instance of this so-called 'time dilation' is the well-known 'twin paradox', where one of two twins goes for a journey and returns to find himself younger than his brother who remained behind. This case allows more scope for muddled thinking because acceleration can be brought into the discussion. Einstein maintained the greater youthfulness of the travelling twin, and admitted that it contradicts the principle of relativity, saying that acceleration must be the cause (Einstein 1918). In this he has been followed by relativists in a long controversy in many journals, much of which ably sustains the character of earlier speculations which Born describes as "monstrous" (Born 1956). Surely there are three conclusive reasons why acceleration can have nothing to do with the time dilation calculated: (i) By taking a sufficiently long journey the effects of acceleration at the start, turn-round and end could be made negligible compared with the uniform velocity time dilation which is proportional to the duration of the journey. (ii) If there is no uniform time dilation, and the effect, if any, is due to acceleration, then the use of a formula depending only on the steady velocity and its duration cannot be justified. (iii) There is, in principle, no need for acceleration. Twin A can get his velocity V before synchronizing his clock with that of twin B as he passes. He need not turn round: he could be passed by C who has a velocity V in the opposite direction, and who adjusts his clock to that of A as he passes. When C later passes B they can compare clock readings. As far as the theoretical experiment is concerned, C's clock can be considered to be A's clock returning without acceleration since, by hypothesis, all the clocks have the same rate when at rest together and change with motion in the same way independently of direction. [fn. I am indebted to Lord Halsbury for pointing this out to me.] (...) The three examples which have been dealt with above show clearly that the difficulties are not paradoxes) but genuine contradictions which follow inevitably from the principle of relativity and the physical interpretations of the Lorentz transformations. The special theory of relativity is therefore untenable as a physical theory."
"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."
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."
"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)."

Pentcho Valev

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