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Computers with closed timelike curves can solve hard problems

Todd A. Brun
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Abstract

A computer which has access to a closed timelike curve, and can thereby send the results of calculations into its own past, can exploit this to solve difficult computational problems efficiently. I give a specific demonstration of this for the problem of factoring large numbers, and argue that a similar approach can solve NP-complete and PSPACE-complete problems. I discuss the potential impact of quantum effects on this result.

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Todd A. Brun. 2002-09-18. Computers with closed timelike curves can solve hard problems. https://doi.org/10.1023/a%3A1025967225931

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