A Problem of Hsiang-Palais-Terng on isoparametric submanifolds
arXiv:math/0312251
Abstract
We solve the problem raised by Hsiang, Palais and Terng in [The topology of isoparametric submanifolds, JDG, 27(1988), 423-460]: Is it possible to have an isoparametric foliation on R^{52} whose marked Dynkin giagram is of type D_4 and with all multiplicities uniformly equal to 4?
10 pages