A Problem of Hsiang-Palais-Terng on isoparametric submanifolds

الأصل · EN

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 R⁵² whose marked Dynkin giagram is of type D₄ and with all multiplicities uniformly equal to 4?