2011/09/18 by Yang Fang, Wen-Ching Winnie Li, Fang, Yang +3 · 1 citation
Mathematics · #Advanced Algebra and Geometry #Advanced Combinatorial Mathematics #FOS: Mathematics #Graph theory and applications #Number Theory (math.NT) #Representation Theory (math.RT)
paper · pdf · doi:10.48550/arxiv.1109.3854
openalex publication_date 2011/09/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Let F be a non-archimedean local field with a finite residue field. To a 2-dimensional finite complex XΓ arising as the quotient of the Bruhat-Tits building X associated to \Sp4(F) by a discrete torsion-free cocompact subgroup Γ of \PGSp4(F), associate the zeta function Z(XΓ, u) which counts geodesic tailless cycles contained in the 1-skeleton of XΓ. Using a representation-theoretic approach, we obtain two closed form expressions for Z(XΓ, u) as a rational function in u. Equivalent statements for XΓ being a Ramanujan complex are given in terms of vertex, edge, and chamber adjacency operators, respectively. The zeta functions of such Ramanujan complexes are distinguished by satisfying the Riemann Hypothesis.