Closed Timelike Curves via Postselection: Theory and Experimental Test of Consistency

Seth Lloyd, Lorenzo Maccone, Raul Garcia-Patron, Vittorio Giovannetti, Yutaka Shikano, Stefano Pirandola, Lee A. Rozema, Ardavan Darabi, Yasaman Soudagar, Lynden K. Shalm, Aephraim M. Steinberg

Research output: Contribution to journalLetterpeer-review


Closed timelike curves (CTCs) are trajectories in spacetime that effectively travel backwards in time: a test particle following a CTC can interact with its former self in the past. A widely accepted quantum theory of CTCs was proposed by Deutsch. Here we analyze an alternative quantum formulation of CTCs based on teleportation and postselection, and show that it is inequivalent to Deutsch's. The predictions or retrodictions of our theory can be simulated experimentally: we report the results of an experiment illustrating how in our particular theory the "grandfather paradox" is resolved.

Original languageEnglish
Article number040403
Number of pages4
JournalPhysical Review Letters
Issue number4
Publication statusPublished - 27 Jan 2011


  • Relativity
  • Timelike Curves

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