2004/06/09 by Alexander Lubotzky, A. Lubotzky, Nikolay Nikolov +3
Mathematics · #20H05 #22E40 #Advanced Algebra and Geometry #Advanced Topics in Algebra #FOS: Mathematics #Geometry and complex manifolds #Group Theory (math.GR) #math.GR #msc:20H05 #msc:22E40
paper · pdf · doi:10.48550/arxiv.math/0406164
34 pages
arxiv created 2004/06/09 · openalex publication_date 2004/06/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We give very precise bounds for the congruence subgroup growth of arithmetic groups. This allows us to determine the subgroup growth of irreducible lattices of semisimple Lie groups. In the most general case our results depend on the Generalized Riemann Hypothesis for number fields but we can state the following unconditional theorem: Let G be a simple Lie group of real rank at least 2, different than D4(\bbc), and let Γ be any non-uniform lattice of G. Let sn(Γ) denote the number of subgroups of index at most n in Γ. Then the limit limn→ ∞ (log sn(Γ))/((log n)2/ log log n) exists and equals a constant γ(G) which depends only on the Lie type of G and can be easily computed from its root system.