
#1
Oct1108, 06:37 AM

P: 2

Assuming a perfectly rigid pole stretching from the Moon to the Earth. Wouldn't pushing on one end be felt instantly at the other?




#2
Oct1108, 06:45 AM

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PF Gold
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#3
Oct1108, 06:54 AM

P: 2





#4
Oct1108, 07:04 AM

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PF Gold
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Communication with no time boundaries? 



#5
Oct1108, 07:18 AM

P: 1

Information and matter are two different things. In a sense matter isn't moving anywhere. Its the communication between each particle?




#6
Oct1108, 07:20 AM

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Zz. 



#7
Oct1108, 07:26 AM

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PF Gold
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#8
Oct1108, 10:40 AM

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PF Gold
P: 2,197

If you push one end of the pole of length L the other end won't start to move until a time t=c/L later,where c is the speed of sound; which is much, much lower than the speed of light . Hence, it is not a very efficient way of transfering information.
Example: the speed of sound in e.g. steel is about 4500 m/s, meaning if you push one end of a 1 km long steel pole the other end won't start to move until 1000/4500=0.2 seconds later. 



#9
Oct1108, 11:09 AM

P: 5,634

New views of the universe as a quantum computer say information is the basic constituent of matter and energy...and anyway, information theory can be viewed as a more general theory of entropy...as usual, everything is linked in mysterious ways we so often fail to discern. Before Einstein, time and space were thought to be fixed, different, unrelated entities.....having little if anything to do with gravity...people would have laughed at the thought they are so intimately related before Einstein's insights. As nature increases entropy over time it also dissipates information....see DECODING THE UNIVERSE, Charles, Seife....also some views in Wikipedia... 


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