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Topic: THE SECRET TO THE TWIN PARADOX
Replies: 5   Last Post: Jan 13, 2013 5:27 AM

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Pentcho Valev

Posts: 3,412
Registered: 12/13/04
Re: THE SECRET TO THE TWIN PARADOX
Posted: Jan 13, 2013 5:27 AM
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Einstein's 1905 false light postulate, combined with the (true) principle of relativity, entails that either observer measures both the other's clock to run slow and the other's rod to be shorter. In many scenarios this is REDUCTIO AD ABSURDUM par excellence so Divine Albert and his worshippers have introduced additional absurdities in order to explain away the original absurdity. In the bug-rivet scenario the original absurdity is blatant:

http://hyperphysics.phy-astr.gsu.edu/Hbase/Relativ/bugrivet.html
"The bug-rivet paradox is a variation on the twin paradox and is similar to the pole-barn paradox.....The end of the rivet hits the bottom of the hole before the head of the rivet hits the wall. So it looks like the bug is squashed.....All this is nonsense from the bug's point of view. The rivet head hits the wall when the rivet end is just 0.35 cm down in the hole! The rivet doesn't get close to the bug....The paradox is not resolved."

It seems special relativity is doomed and yet... if length contraction alone produces absurdities, then nothing can stop Einsteinians from ad hoc introducing length elongation: the combination of length contraction and length elongation resolves any paradox, Divine Einstein, yes we all believe in relativity, relativity, relativity:

http://brianclegg.blogspot.com/2011_11_01_archive.html
Brian Clegg: "Here's the scenario. We've got a table with a 10mm deep hole in it. At the bottom of the hole a beetle is happily beetling about, unaware that we are about to fire a rivet into the hole. The good news is that the shank of the rivet, the bit that will go into the hole, is only 8mm long, leaving room for our (rather small) beetle to feel safe and snug. (...) Let's follow the event from the beetle's viewpoint. Down comes the rivet and slams into the table. At the moment before the impact the rivet is still just 5mm long as far as the bug is concerned. But here's the thing. Just because the head of the rivet has come to a sudden stop doesn't mean the whole rivet does. A wave has to pass along the rivet to its end saying 'Stop!' The end of the rivet will just keep on going until this wave, typically travelling at the speed of sound, reaches it. That fast-moving end will crash into the beetle long before the wave arrives. It will then send a counter wave back up the rivet and after a degree of shuddering will eventually settle down as an 8 mm rivet in a 10 mm hole. Too late, though, for that bug. Isn't physics great?"

http://math.ucr.edu/~jdp/Relativity/Bug_Rivet.html
John de Pillis Professor of Mathematics: "In fact, special relativity requires that after collision, the rivet shank length increases beyond its at-rest length d."

Pentcho Valev



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