摘要
We introduce a structural approach to study Lagrangian submanifolds of the complex hyperquadric in arbitrary dimension by using its family of non-integrable almost product structures.In particular,we define local angle functions encoding the geometry of the Lagrangian submanifold at hand.We prove that these functions are constant in the special case that the Lagrangian immersion is the Gauss map of an isoparametric hypersurface of a sphere and give the relation with the constant principal curvatures of the hypersurface.We also use our techniques to classify all minimal Lagrangian submanifolds of the complex hyperquadric which have constant sectional curvatures and all minimal Lagrangian submanifolds for which all local angle functions,respectively all but one,coincide.
基金
supported by the Tsinghua University-KU Leuven Bilateral Scientific Cooperation Fund
collaboration project funded by National Natural Science Foundation of China
supported by National Natural Science Foundation of China(Grant Nos.11831005 and 11671224)
supported byNational Natural Science Foundation of China(Grant Nos.11831005 and 11671223)
supported by National Natural Science Foundation of China(Grant No.11571185)
the Research Foundation Flanders(Grant No.11961131001)
supported by the Excellence of Science Project of the Belgian Government(Grant No.GOH4518N)
supported by the KU Leuven Research Fund(Grant No.3E160361)
the Fundamental Research Funds for the Central Universities。