Linear embeddings of Grassmannians and ind-Grassmannians
Journal of Lie Theory, Special issue dedicated to the memory of Joseph A. Wolf, Volume 36 (2026) no. 1, pp. 213-268

By a Grassmannian we understand a usual complex Grassmannian or possibly an orthogonal or symplectic Grassmannian. We classify, with few exceptions, linear embeddings of Grassmannians into larger Grassmannians, where the linearity requirement is the condition that the embedding induces an isomorphism on Picard groups. This classification implies that most linear embeddings of Grassmannians are equivariant.

A linear ind-Grassmannian is the direct limit of a chain of linear embeddings of Grassmannians. We conclude the paper by classifying linear embeddings of linear ind-Grassmannians.

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Accepted:
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DOI: 10.5802/jlt.1425
Classification: 14E25, 14L30, 14M15
Keywords: Grassmannian, isotropic Grassmannian, ind-Grassmannian, linear embedding, equivariant embedding

Penkov, Ivan  1 ; Tsanov, Valdemar  2 , 1

1 Constructor University, 28759 Bremen, Germany
2 Institute of Mathematics and Informatics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 8, Sofia 1113, Bulgaria
Penkov, Ivan; Tsanov, Valdemar. Linear embeddings of Grassmannians and ind-Grassmannians. Journal of Lie Theory, Special issue dedicated to the memory of Joseph A. Wolf, Volume 36 (2026) no. 1, pp. 213-268. doi: 10.5802/jlt.1425
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