The quantum physics of time travel

monicasharma
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anyone read or have opinions on The Quantum Physics of Time Travel by David Deutsch and Michael Lockwood?

He talks about closed time like curves and if we followed them it would end up taking us to the past to participate in events, shake hands with former selves etc

I was a little confused on the concept of closed time like curves. He related the topic to Godel's solutions to Einsteins equations. He then also talked about possible finding the CTC's in black holes or moving two ends of wormholes to create a CTC.

I got lost around there. I was trying to see the connection between that and the grandfather paradox

anyone know a thing or two? I'd appreciate any help. Thanks!

http://philosci40.unibe.ch/lehre/wi...teien/11 Deutsch Lockwood Scientific American
 
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Of course, the equations are more easily shown to work with something simpler than a human, more like an electron.

A closed timelike curve is not a paradox. It is more like traveling into the past to save a grandfather's life! This is because of the fact that the curve is closed; you wind up where you started.
 
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