September 15.

Goo Ishikawa (Hokkaido University).
Determinacy, Transversality and Lagrange Stability.

For a class of singular Lagrange varieties, open Whitney umbrellas, there are given Arnol'd-Mather type characterisations of Lagrange stability via transversality in isotropic jet spaces. Also determinacy of Lagrange stable isotropic map-germs is considered. As an application, we provide an example of Lagrange stable isotropic map-germ of corank one in itself and of corank two after the Lagrange projection.