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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Keywords: Grassmannian, isotropic Grassmannian, ind-Grassmannian, linear embedding, equivariant embedding
Penkov, Ivan  1 ; Tsanov, Valdemar  2 , 1
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
@article{10_5802_jlt_1425,
author = {Penkov, Ivan and Tsanov, Valdemar},
title = {Linear embeddings of {Grassmannians} and {ind-Grassmannians}},
journal = {Journal of Lie Theory},
pages = {213--268},
year = {2026},
publisher = {XXXX},
volume = {36},
number = {1},
doi = {10.5802/jlt.1425},
language = {en},
url = {https://jolt.centre-mersenne.org/articles/10.5802/jlt.1425/}
}
TY - JOUR AU - Penkov, Ivan AU - Tsanov, Valdemar TI - Linear embeddings of Grassmannians and ind-Grassmannians JO - Journal of Lie Theory PY - 2026 SP - 213 EP - 268 VL - 36 IS - 1 PB - XXXX UR - https://jolt.centre-mersenne.org/articles/10.5802/jlt.1425/ DO - 10.5802/jlt.1425 LA - en ID - 10_5802_jlt_1425 ER -
[1] Ind-varieties of generalized flags as homogeneous spaces for classical ind-groups, Int. Math. Res. Not., Volume 2004 (2004) no. 55, pp. 2935-2953 | Zbl | DOI | MR
[2] Maximal subgroups of classical group, Tr. Mosk. Mat. O.-va, Volume 1 (1952), pp. 39-166 | Zbl | MR
[3] Semisimple subalgebras of semisimple Lie algebras, Mat. Sb., N. Ser., Volume 30 (1952), pp. 349-462 English translation in Am. Math. Soc. Transl., Series 2 6 (1957), pp. 111–244 | Zbl | MR
[4] Linear algebraic groups, Graduate Texts in Mathematics, 21, Springer, 1975, xv+247 pages | Zbl | MR
[5] The Picard group of a G-variety, Algebraische Transformationsgruppen und Invariantentheorie (DMV Seminar), Volume 13, Birkhäuser, 1989, pp. 77-87 | Zbl | DOI
[6] Tensors: Geometry and Applications, Graduate Studies in Mathematics, 128, American Mathematical Society, 2012, xx+439 pages | Zbl | MR
[7] On the projective geometry of rational homogeneous varieties, Comment. Math. Helv., Volume 78 (2003) no. 1, pp. 65-100 | Zbl | DOI | MR
[8] Inclusion relations between transitive compact transformation groups, Tr. Mosk. Mat. O.-va, Volume 11 (1962), pp. 199-242 English translation in Am. Math. Soc. Transl., Series 2 50 (1966), pp. 5–58 | Zbl | MR
[9] Linear ind-Grassmannians, Pure Appl. Math. Q., Volume 10 (2014) no. 2, pp. 289-323 | Zbl | MR | DOI
[10] The KP hierarchy and infinite-dimensional Grassmann manifolds, Theta functions, Bowdoin 1987 (Proceedings of Symposia in Pure Mathematics), Volume 49.1, American Mathematical Society, 1987, pp. 51-66 | Zbl | DOI | MR
[11] Sur les analogues algébriques des groupes semi-simples complexes, Colloque d’algèbre supérieure, Bruxelles, 19-22 décembre 1956, Centre Belge de Recherches Mathématiques, 1957, pp. 261-289 | Zbl | MR
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