Abstract
Given a smooth hyperplane section H of a rational homogeneous space G/P with Picard number one, we address the question whether it is always possible to lift an automorphism of H to the Lie group G, or more precisely to Aut(G/P). Using linear spaces and quadrics in H, we show that the answer is positive up to a few well understood exceptions related to Jordan algebras. When G/P is an adjoint variety, we show how to describe Aut(H) completely, extending results obtained by Prokhorov and Zaidenberg when G is the exceptional group G2.
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References
Bai, C., Fu, B., Manivel, L: On Fano complete intersections in rational homogeneous varieties. Math. Z. 295, 289–308 (2020)
Beauville, A.: Fano contact manifolds and nilpotent orbits. Comment. Math. Helv. 73, 566–583 (1998)
Benedetti, V.: Bisymplectic Grassmannians of planes. J. Algebraic Combin. 53, 851–880 (2021)
Benedetti, V., Perrin, N.: Cohomology of hyperplane sections of (co)adjoint varieties in preparation (2021)
Bourbaki N.: Lie groups and lie algebras, chapters 4–6, translated from the 1968 French original, elements of mathematics, Springer (2002)
Buczyński, J.: Legendrian subvarieties of projective space. Geom. Dedicata 118, 87–103 (2006)
Chaput, P.-E.: Scorza varieties and Jordan algebras. Indag. Math. 14, 169–182 (2003)
Dedieu, Th., Manivel, L.: On the automorphisms of Mukai varieties. Math. Z. 300, 3577–3621 (2022)
Demazure, M.: Automorphismes et déformations des variétés de borel. Invent. Math. 39, 179–186 (1977)
Ein, L., Shepherd-Barron, N.: Some special Cremona transformations. Am. J. Math. 111, 783–800 (1989)
Fu, B., Hwang, J. -M.: Classification of non-degenerate projective varieties with non-zero prolongation and application to target rigidity. Invent. Math. 189, 457–513 (2012)
Iskovskikh, V., Prokhorov, Y.: Fano varieties, Algebraic geometry V. Encyclopaedia Math. Sci. 47, 1–247 (1999)
Kuznetsov, A.: On Küchle varieties with Picard number greater than 1. Izv. Math. 79, 698–709 (2015)
Kuznetsov, A., Prokhorov, Y., Shramov, C.: Hilbert schemes of lines and conics and automorphism groups of Fano threefolds. Jpn. J. Math. 13, 109–185 (2018)
Landsberg, J.M., Manivel, L.: Construction and classification of complex simple Lie algebras via projective geometry. Selecta Math. 8, 137–159 (2002)
Landsberg, J. M., Manivel, L: On the projective geometry of rational homogeneous varieties. Comment. Math. Helv. 78, 65–100 (2003)
LiE: A computer algebra package for Lie group computations. available online at http://www.mathlabo.univ-poitiers.fr/~maavl/LiE/ (1992)
Matsushima, Y.: Sur la structure du groupe d’homéomorphismes analytiques d’une certaine variété kählérienne. Nagoya Math. J. 11, 145–150 (1957)
Mihai, I.: Odd symplectic flag manifolds. Transform. Groups 12, 573–599 (2007)
Mukai, S.: Curves, K3 surfaces and Fano 3-folds of genus ≤ 10. In: Algebraic geometry and commutative algebra, Kinokuniya, vol I. pp 357–377 (1988)
Nishio, A., Yasukura, O.: Orbit decomposition of Jordan matrix algebras of order three under the automorphism groups. J. Math. Sci. Univ. Tokyo 17, 387–417 (2010)
Onishchik, AL: Inclusion relations between transitive compact transformation groups. Trudy Moskov. Mat. Obs. 11, 199–242 (1962)
Ottaviani, G., Rubei, E.: Quivers and the cohomology of homogeneous vector bundles. Duke Math. J. 132, 459–508 (2006)
Piontkowski, J., Van de Ven, A.: The automorphism group of linear sections of the Grassmannians G(1,N). Doc. Math. 4, 623–664 (1999)
Prokhorov, Y., Zaidenberg, M.: Fano-Mukai fourfolds of genus 10 as compactifications of \(\mathbb {C}^4\). Eur. J. Math. 4, 1197–1263 (2018)
Prokhorov, Y., Zaidenberg, M.: Fano-Mukai fourfolds of genus 10 and their automorphism groups. Eur. J. Math. 8, 561–572 (2022)
Reid, M.: The complete intersection of two or more quadrics. http://homepages.warwick.ac.uk/masda/3folds/qu.pdf (1972)
Springer, T.: Regular elements of finite reflection groups. Invent. Math. 25, 159–198 (1974)
Springer, T.: Jordan algebras and algebraic groups, Classics in Mathematics, Springer (1998)
Tevelev, E.A.: Projective duality and homogeneous spaces in Encyclopaedia of Mathematical Sciences, vol. 133, Invariant Theory and Algebraic Transformation Groups IV, Springer (2005)
Tits, J.: Groupes semi-simples complexes et géométrie projective. Séminaire Bourbaki 3, 115–125 (1956)
Zak, F.L.: Tangents and secants of algebraic varieties, Translations of Mathematical Monographs 127 AMS (1993)
Acknowledgements
We would like to thank Mikhail Zaidenberg for his useful comments on a preliminary version of the paper. We would also like to express our gratitude to Alexander Kuznetsov for his careful and insightful reading, which led to significant improvements.
Funding
This work received support from the ANR project FanoHK, grant ANR-20-CE40-0023. The first author is partially supported by the EIPHI Graduate School (contract ANR-17-EURE-0002).
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Manivel, L., Benedetti, V. On the Automorphisms of Hyperplane Sections of Generalized Grassmannians. Transformation Groups (2022). https://doi.org/10.1007/s00031-022-09757-1
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DOI: https://doi.org/10.1007/s00031-022-09757-1