JournalsprimsVol. 31 , No. 1DOI 10.2977/prims/1195164788

Automorphisms of the Extended Affine Root System and Modular Property for the Flat Theta Invariants

  • Ikuo Satake

    Osaka University, Japan
Automorphisms of the Extended Affine Root System and Modular Property for the Flat Theta Invariants cover

Abstract

We define the central extension ~Aut+(R) of the automorphism group Aut+(R) of the extended affine root system. We give the action of ~Aut+(R) on the flat theta invariants (theta functions). This describes the modular property for the flat theta invariants.