String Quantum Symmetries and the SL(2,Z) Group
arXiv:hep-th/9306047 · doi:10.1016/0370-2693(93)90977-P
Abstract
We prove, using arguments relying only on the "special Kähler" structure of the moduli space of the Calabi-Yau three-fold, that in the case of one single modulus the quantum modular group of the string effective action corresponding to Calabi-Yau vacua can not be SL(2,${Z\kern -4.6pt Z}$).
11 pages, Plain Tex, INFN-CA-93-12