Journal of the Mathematical Society of Japan

The geometry of symmetric triad and orbit spaces of Hermann actions


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We introduce the notion of symmetric triad, which is a generalization of the notion of irreducible root system, and study its fundamental properties. Applying these results, we study the orbit spaces of Hermann actions on compact symmetric spaces.

Article information

J. Math. Soc. Japan, Volume 63, Number 1 (2011), 79-136.

First available in Project Euclid: 27 January 2011

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 53C35: Symmetric spaces [See also 32M15, 57T15]
Secondary: 17B22: Root systems 53C40: Global submanifolds [See also 53B25]

Hermann action austere submanifold symmetric triad


IKAWA, Osamu. The geometry of symmetric triad and orbit spaces of Hermann actions. J. Math. Soc. Japan 63 (2011), no. 1, 79--136. doi:10.2969/jmsj/06310079.

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