Abstract
We consider a toy model of the interaction of a qubit with an exotic space-time containing a timelike curve. Consistency seems to require that the global evolution of the qubit be nonunitary. Given that quantum mechanics is globally unitary, this then is an example of a quantum gravity information paradox. However, we show that a careful analysis of the problem in the Heisenberg picture reveals an underlying unitarity, thus resolving the paradox.
- Received 3 May 2007
DOI:https://doi.org/10.1103/PhysRevA.76.012336
©2007 American Physical Society