The Quarterly Journal of Mathematics Advance Access published online on December 4, 2007
The Quarterly Journal of Mathematics, doi:10.1093/qmath/ham040
DEFORMATIONS OF HYPERCOMPLEX STRUCTURES ASSOCIATED TO HEISENBERG GROUPS
Department of Mathematics, Florida International University, Miami, FL 33199, USA
Department of Mathematics and Computer Science, University of Southern Denmark, Campusvej 55, Odense M, DK-5230, Denmark

Department of Mathematics, University of California at Riverside, Riverside, CA 92521, USA
Corresponding author. E-mail: ypoon{at}math.ucr.edu
Received 5 January 2007;
| Abstract |
|---|
Let X be a compact quotient of the product of the real Heisenberg group H4m+1 of dimension 4m + 1 and the three-dimensional real Euclidean space R3. A left-invariant hypercomplex structure on H4m+1 x R3 descends onto the compact quotient X. The space X is a hyperholomorphic fibration of 4-tori over a 4m-torus. We calculate the parameter space and obstructions to deformations of this hypercomplex structure on X. Using our calculations, we show that all small deformations generate invariant hypercomplex structures on X but not all of them arise from deformations of the lattice. This is in contrast to the deformations on the 4m-torus.

E-mail: