arXiv 1701.080492017-01math.COcs.DSmath.DS

On a conjecture of Sokal concerning roots of the independence polynomial

Han Peters, Guus Regts

备注：: We have updated the file partly based on some comments from a referee. The file is now 20 pages and contains one figure. Accepted in Michigan Mathematical Journal

英文摘要：

A conjecture of Sokal (2001) regarding the domain of non-vanishing for independence polynomials of graphs, states that given any natural number $Δ\ge 3$, there exists a neighborhood in $\mathbb C$ of the interval $[0, \frac{(Δ-1)^{Δ-1}}{(Δ-2)^Δ})$ on which the independence polynomial of any graph with maximum degree at most $Δ$ does not vanish. We show here that Sokal's Conjecture holds, as well as a multivariate version, and prove optimality for the domain of non-vanishing. An important step is to translate the setting to the language of complex dynamical systems.

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