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On the flux phase conjecture at half-filling: an improved proof

Nicolas Macris·Bruno Nachtergaele
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Abstract

We present a simplification of Lieb's proof of the flux phase conjecture for interacting fermion systems -- such as the Hubbard model --, at half filling on a general class of graphs. The main ingredient is a procedure which transforms a class of fermionic Hamiltonians into reflection positive form. The method can also be applied to other problems, which we briefly illustrate with two examples concerning the $t-V$ model and an extended Falicov-Kimball model.

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Nicolas Macris, Bruno Nachtergaele. 1996-04-08. On the flux phase conjecture at half-filling: an improved proof. https://doi.org/10.1007/bf02199361

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