Entropy and the clique polynomial
نویسنده
چکیده
This paper gives a sharp lower bound on the spectral radius ρ(A) of a reciprocal Perron–Frobenius matrix A ∈ M2g(Z), and shows in particular that ρ(A) ≥ (3 + √ 5)/2. This bound supports conjectures on the minimal entropy of pseudo-Anosov maps. The proof is based on a study of the curve complex of a directed graph.
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