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arXiv · 1704.00682

Quasifree stochastic cocycles and quantum random walks

Alexander C. R. Belton·Michal Gnacik·J. Martin Lindsay·Ping Zhong
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Abstract

The theory of quasifree quantum stochastic calculus for infinite-dimensional noise is developed within the framework of Hudson-Parthasarathy quantum stochastic calculus. The question of uniqueness for the covariance amplitude with respect to which a given unitary quantum stochastic cocycle is quasifree is addressed, and related to the minimality of the corresponding stochastic dilation. The theory is applied to the identification of a wide class of quantum random walks whose limit processes are driven by quasifree noises.

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Alexander C. R. Belton, Michal Gnacik, J. Martin Lindsay, Ping Zhong. 2017-04-03. Quasifree stochastic cocycles and quantum random walks. https://arxiv.org/abs/1704.00682

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