Article ID Journal Published Year Pages File Type
4587597 Journal of Algebra 2009 16 Pages PDF
Abstract

We study the commutator subgroup of integral orthogonal groups belonging to indefinite quadratic forms. We show that the index of this commutator is 2 for many groups that occur in the construction of moduli spaces in algebraic geometry, in particular the moduli of K3 surfaces. We give applications to modular forms and to computing the fundamental groups of some moduli spaces.

Related Topics
Physical Sciences and Engineering Mathematics Algebra and Number Theory