Abstract
We consider Deutsch’s computational model of a quantum system evolving in a spacetime containing closed timelike curves. Although it is known that this model predicts nonlinear and nonunitary evolutions of the system, we demonstrate that it also gives rise to evolutions which are a discontinuous function of the input state. These discontinuities persist for the most natural modifications of Deutsch’s approach.
- Received 11 January 2010
DOI:https://doi.org/10.1103/PhysRevD.81.087501
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