December 14

December 14 - Causality One things happens that leads to...

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December 14, 2007 Causality- One things happens that leads to another things - going back and killing your younger self would not be possible, because then you would not exist to kill yourself - Possibilities law of nature prevents you from killing grandfather - Polchinski’s Paradox o Two mouths of a wormhole and you shoot a particle at one mouth and the connection between the two wormholes, the particle will soon come out of the other wormhole Shoot a billiard ball at one wormhole and it comes out before you shoot it from the other wormhole and knocks the one you are about to shoot Can’t happen - Thorne’s way of getting around this: o You shoot the pool ball at the wormhole at such an angle that the ball coming out of the other will knock it in Hawking’s chronology protection conjecture - The laws of physics forbid time machines o “to keep the world safe for historians” Exotic Matter Does Exotic Matter exist? -
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This note was uploaded on 02/26/2008 for the course ASTR 2030 taught by Professor Mb during the Fall '06 term at Colorado.

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December 14 - Causality One things happens that leads to...

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