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Time Travel without Regrets

David Lindley

Published Feb 1, 2011• 1 citation
Publisher

Abstract

Time travel isn’t forbidden by physical laws. A new consistency condition for time traveling quantum states eliminates any possibility of so-called grandfather paradoxes, in which a time-traveler kills her own ancestor.
DOI
10.1103/physrevfocus.27.5

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Focus: Time Travel without Regrets

David Lindley

Time travel isn’t forbidden by physical laws. A new consistency condition for time traveling quantum states eliminates any possibility of so-called grandfather paradoxes, in which a time-traveler kills her own ancestor.

•Feb 4, 2011•1 citation
A time machine that sends information back to the past may, in principle, be built using closed time-like curves. However, the realization of a time machine must be congruent with apparent paradoxes that arise from traveling back in time. Using a simple model to analyze the consequences of time travel, we show that several paradoxes, including the grandfather paradox and Deutsch's unproven theorem paradox, are precluded by basic axioms of probability. However, our model does not prohibit traveling back in time to affect past events in a self-consistent manner.