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On cones tangent to Schubert varieties of type $ D_n$


Authors: M. V. Ignat′ev and A. A. Shevchenko
Translated by: M. V. Ignat′ev
Original publication: Algebra i Analiz, tom 27 (2015), nomer 4.
Journal: St. Petersburg Math. J. 27 (2016), 609-623
MSC (2010): Primary 14L30
DOI: https://doi.org/10.1090/spmj/1408
Published electronically: June 2, 2016
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Abstract | References | Similar Articles | Additional Information

Abstract: It is proved that the tangent cones to Schubert subvarieties of the flag variety of a reductive group with root system of type $ D_n$ do not coincide if they correspond to different basic involutions in the Weyl group.


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Additional Information

M. V. Ignat′ev
Affiliation: Division of Algebra and Geometry, Samara State University, Russia
Email: mihail.ignatev@gmail.com

A. A. Shevchenko
Affiliation: Division of Algebra and Geometry, Samara State University, Russia
Email: shevchenko.alexander.1618@gmail.com

DOI: https://doi.org/10.1090/spmj/1408
Keywords: Shubert variety, tangent cone, Kostant--Kumar polynomial, coadjoint orbit
Received by editor(s): February 2, 2015
Published electronically: June 2, 2016
Additional Notes: Partially supported by RFBR (grants nos. 14-01-31052 and 14-01-97017). The first author was partially supported by the Dynasty Foundation, by Max Planck Institute for Mathematics, and by the Ministry of Science and Education of the Russian Federation.
Article copyright: © Copyright 2016 American Mathematical Society

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