Hostname: page-component-7b7567c8c-7pwfn Total loading time: 0 Render date: 2026-11-15T19:50:22.156Z Has data issue: false hasContentIssue false

Cuspidal Modular Symbols are Transportable

Published online by Cambridge University Press:  01 February 2010

William A. Stein
Affiliation:
Department of Mathematics, Harvard University, One Oxford Street, Cambridge, MA 02138, USA, was@math.harvard.edu, http://modular.fas.harvard.edu/
Helena A. Verrill
Affiliation:
Institute for Mathematics, University of Hannover, Welfengarten 1, 30167 Hannover, Germany, verrill@math.uni-hannover.de, http://hverrill.net

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the 'Save PDF' action button.

Modular symbols of weight 2 for a congruence subgroup Γ satisfy the identity {α,γ,(α)}={β,γ(β)} for all α,β in the extended upper half plane and γ ∊ Γ. The analogue of this identity is false for modular symbols of weight greater than 2. This paper provides a definition of transportable modular symbols, which are symbols for which an analogue of the above identity holds, and proves that every cuspidal symbol can be written as a transportable symbol. As a corollary, an algorithm is obtained for computing periods of cuspforms.

Information

Type
Research Article
Copyright
Copyright © London Mathematical Society 2001