Relation between Feynman cycles and off-diagonal long-range order.
نویسنده
چکیده
The usual order parameter for Bose-Einstein condensation involves the off-diagonal correlation function of Penrose and Onsager, but an alternative is Feynman's notion of infinite cycles. We present a formula that relates both order parameters. We discuss its validity with the help of rigorous results and heuristic arguments. The conclusion is that infinite cycles do not always represent the Bose condensate.
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ورودعنوان ژورنال:
- Physical review letters
دوره 97 17 شماره
صفحات -
تاریخ انتشار 2006