Complex zero-free regions at large |q| for multivariate Tutte polynomials (alias Potts-model partition functions) with general complex edge weights
نویسندگان
چکیده
We find zero-free regions in the complex plane at large |q| for the multivariate Tutte polynomial (also known in statistical mechanics as the Potts-model partition function) ZG(q,w) of a graph G with general complex edge weights w = {we}. This generalizes a result of Sokal [22] that applied only within the complex antiferromagnetic regime |1+we| ≤ 1. Our proof uses the polymer-gas representation of the multivariate Tutte polynomial together with the Penrose identity.
منابع مشابه
Potts - model partition functions ) with general complex edge weights
We find zero-free regions in the complex plane at large |q| for the multivariate Tutte polynomial (also known in statistical mechanics as the Potts-model partition function) ZG(q,w) of a graph G with general complex edge weights w = {we}. This generalizes a result of Sokal [22] that applied only within the complex antiferromagnetic regime |1+we| ≤ 1. Our proof uses the polymer-gas representatio...
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 103 شماره
صفحات -
تاریخ انتشار 2013