# Time travel paradoxes, path integrals, and the many worlds interpretation of quantum mechanics

@article{Everett2004TimeTP, title={Time travel paradoxes, path integrals, and the many worlds interpretation of quantum mechanics}, author={Allen E. Everett}, journal={Physical Review D}, year={2004}, volume={69}, pages={124023} }

We consider two approaches to evading paradoxes in quantum mechanics with closed timelike curves. In a model similar to Politzer's, assuming pure states and using path integrals, we show that the problems of paradoxes and of unitarity violation are related; preserving unitarity avoids paradoxes by modifying the time evolution so that improbable events become certain. Deutsch has argued, using the density matrix, that paradoxes do not occur in the ``many worlds interpretation.'' We find that in… Expand

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