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Published on: May 30, 2014
Emergence of Constructor-Based Irreversibility in Quantum Systems: Theory and Experiment
Chiara Marletto1, Vlatko Vedral1, Laura T Knoll2
1Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom and Fondazione ISI, Via Chisola 5, Torino, Italy and Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 and Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542.
Abstract:
How irreversibility arises in a universe with time-reversal symmetric laws is a central problem in physics. In this Letter, we discuss a radically different take on the emergence of irreversibility, adopting the recently proposed constructor theory framework. Irreversibility is expressed as the requirement that a task is possible, while its inverse is not. We prove the compatibility of such irreversibility with quantum theory's time-reversal symmetric laws, using a dynamical model based on the universal quantum homogenizer. We also test the physical realizability of this model by means of an experimental demonstration with high-quality single-photon qubits.
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