Revisiting integer factorization using closed timelike curves

  • Soumik Ghosh
  • Arnab Adhikary
  • Goutam PaulEmail author


Closed timelike curves are relativistically valid objects allowing time travel to the past. Treating them as computational objects opens the door to a wide range of results which cannot be achieved using non-relativistic quantum mechanics. Recently, research in classical and quantum computation has focused on effectively harnessing the power of these curves. In particular, Brun (Found Phys Lett 16:245–253, 2003) has shown that CTCs can be utilized to efficiently solve problems like factoring and quantified satisfiability problem. In this paper, we find a flaw in Brun’s algorithm and propose a modified algorithm to circumvent the flaw.


Closed timelike curves D-CTC Factoring P-CTC 


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institute for Quantum ComputingUniversity of WaterlooWaterlooCanada
  2. 2.Centre for High Energy Physics, Department of PhysicsIndian Institute of ScienceBangaloreIndia
  3. 3.Cryptology and Security Research Unit, R. C. Bose Centre for Cryptology and SecurityIndian Statistical InstituteKolkataIndia

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