arXiv · 1203.3581
Two quasi-free states on a CAR or CCR algebra are shown to generate quasi-equivalent representations unless they are disjoint.
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Taku Matsui, Shigeru Yamagami. 2012-03-15. Kakutani Dichotomy on Free States. https://doi.org/10.1007/s11005-012-0579-0
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