arXiv 0803.23912008-03-17math.DG

Orbits of s-representations with degenerate Gauss mappings

Osamu Ikawa, Takashi Sakai, Hiroyuki Tasaki

备注：: 27 pages

英文摘要：

In this paper we study tangentially degeneracy of the orbits of s-representations in the sphere. We show that an orbit of an s-representation is tangentially degenerate if and only if it is through a long root, or a short root of restricted root system of type G_2. Moreover these orbits provide many new examples of tangentially degenerate submanifolds which satisfy the Ferus equality.

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