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arXiv · 2105.10772

Four Amazing Positivities with Dimers/i-Matchings

Paul Federbush
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Abstract

We collect a number of striking recent results in a study of dimers on infinite regular bipartite lattices and also on regular bipartite graphs. We clearly separate rigorously proven results from conjectures. A primary goal is to show people: here is a field which is ripe for further interesting research. We separate four classes of endeavor, of which we here extract two items to whet one's appetite. Primo,for hyper-rectangular lattices of every dimension the first 20 virial coefficients are positive. (One has no understanding of this yet!) Secondo, all regular bipartite graphs with less than $14$ vertices satisfy graph positivity, defined below. (Here there is some understanding.)

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Paul Federbush. 2021-05-22. Four Amazing Positivities with Dimers/i-Matchings. https://arxiv.org/abs/2105.10772

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