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arXiv · 0708.0449

Unitary Solution to a Quantum Gravity Information Paradox

T. C. Ralph
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Abstract

We consider a toy model of the interaction of a qubit with an exotic space-time containing a time-like curve. Consistency seems to require that the global evolution of the qubit be non-unitary. 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.

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T. C. Ralph. 2007-08-03. Unitary Solution to a Quantum Gravity Information Paradox. https://doi.org/10.1103/physreva.76.012336

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