Traces in Complex Hyperbolic Triangle Groups

Pratoussevitch, Anna ORCID: 0000-0003-2248-6382
Traces in Complex Hyperbolic Triangle Groups. Geom. Dedicata 111 (2005), 159-185..

[img] Text

Download (265kB)


We present several formulas for the traces of elements in complex hyperbolic triangle groups generated by complex reflections. The space of such groups of fixed signature is of real dimension one. We parameterise this space by a real invariant alpha of triangles in the complex hyperbolic plane. The main result of the paper is a formula, which expresses the trace of an element of the group as a Laurent polynomial in exp(i alpha) with coefficients independent of alpha and computable using a certain combinatorial winding number. We also give a recursion formula for these Laurent polynomials and generalise the trace formulas for the groups generated by complex mu-reflections. We apply these formulas to prove some discreteness and some non-discreteness results for complex hyperbolic triangle groups.

Item Type: Article
Additional Information: 22 pages, 1 figure; prop. 11 added, typos corrected; cor. 19 removed (not correct)
Uncontrolled Keywords: math.DG, math.DG, 51M10 (Primary); 53C55; 57M50 (Secondary)
Depositing User: Symplectic Admin
Date Deposited: 11 Apr 2016 08:56
Last Modified: 12 Nov 2019 14:05
Related URLs:
Repository Staff Access