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Geometric mitosis and Newton-Okounkov polytopes
P. 1484–1487.
In [K], a convex-geometric algorithm was introduced for building new analogs of Gelfand–Zetlin polytopes for arbitrary reductive groups. Conjecturally, these polytopes coincide with the Newton–Okounkov polytopes of flag varieties for a geometric valuation. I outline an algorithm (geometric mitosis) for finding collec- tion of faces in these polytopes that represent a given Schubert cycle. For GL_n and Gelfand–Zetlin polytopes, this algorithm reduces to a geometric version of Knutson–Miller mitosis introduced in [KST].
In book
Vol. 11. Issue 2. , Zürich: European Mathematical Society Publishing house, 2014.
Kiritchenko V., Journal of Combinatorial Theory, Series A 2025 Vol. 213 Article 106022
We construct simple geometric operations on faces of the Cayley sum of two polytopes. These operations can be thought of as convex geometric counterparts of divided difference operators in Schubert calculus. We show that these operations give a uniform construction of Knutson–Miller mitosis in the type A and Fujita mitosis in the type C on Kogan faces of Gelfand–Zetlin ...
Added: March 18, 2025
Deviatov R., / Series arXiv "math". 2025.
We sketch the proof of a connection between the canonical (0-)dimension of semisimple split simply connected groups and cohomology of their full flag varieties. Using this connection, we get a new estimate of the canonical (0-)dimension of simply connected split exceptional groups of type E understood as a group. ...
Added: March 12, 2025
Kiritchenko V., Padalko M., , in: Interactions with Lattice Polytopes Magdeburg, Germany, September 2017.: Springer, 2022. P. 233–249.
A Newton–Okounkov polytope of a complete flag variety can be turned into a convex geometric model for Schubert calculus. Namely, we can represent Schubert cycles by linear combinations of faces of the polytope so that the intersection product of cycles corresponds to the set-theoretic intersection of faces (whenever the latter are transverse). We explain the ...
Added: January 31, 2023
Evgeny Smirnov, Anna Tutubalina, European Journal of Combinatorics 2023 Vol. 107 Article 103613
Schubert polynomials for the classical groups were defined by S.Billey and M.Haiman in 1995; they are polynomial representatives of Schubert classes in a full flag variety over a classical group. We provide a combinatorial description for these polynomials, as well as their double versions, by introducing analogues of pipe dreams, or RC-graphs, for Weyl groups ...
Added: September 14, 2022
Kiritchenko V., International Mathematics Research Notices 2023 Vol. 2023 No. 4 P. 3305–3328
A classical result of Schubert calculus is an inductive description of Schubert cycles using divided difference (or push-pull) operators in Chow rings. We define convex geometric analogs of push-pull operators and describe their applications to the theory of Newton-Okounkov convex bodies. Convex geometric push-pull operators yield an inductive construction of Newton-Okounkov polytopes of Bott-Samelson varieties. ...
Added: January 31, 2022
Mathematical Society of Japan, 2016.
This volume contains the proceedings of the 5th MSJ Seasonal Institute on Schubert Calculus, held at Osaka City University, from September 17–27, 2012. It is recommended for all researchers and graduate students who are interested in Schubert calculus and its many connections and applications to related areas of mathematics, such as geometric representation theory, combinatorial ...
Added: October 19, 2020
Kiritchenko V., Padalko M., / Series arXiv "math". 2018.
A Newton-Okounkov polytope of a complete flag variety can be turned into a convex geometric model for Schubert calculus. Namely, we can represent Schubert cycles by linear combinations of faces of the polytope so that the intersection product of cycles corresponds to the set-theoretic intersection of faces (whenever the latter are transverse). We explain the ...
Added: October 15, 2019
Kiritchenko V., Arnold Mathematical Journal 2019 Vol. 5 No. 2-3 P. 355–371
For classical groups SL(n), SO(n) and Sp(2n), we define uniformly geometric valuations on the corresponding complete flag varieties. The valuation in every type comes from a natural coordinate system on the open Schubert cell and is combinatorially related to the Gelfand-Zetlin pattern in the same type. In types A and C, we identify the corresponding ...
Added: October 15, 2019
Smirnov E., В кн.: Тезисы докладов седьмой школы-конференции "Алгебры Ли, алгебраические группы и теория инвариантов".: Самара: Инсома-пресс, 2018. С. 43–44.
We define simplicial complexes for slide polynomials and show that they are always homeomorphic to balls or spheres. ...
Added: October 7, 2019
Valentina Kiritchenko, / Series arXiv "math". 2018.
We compute the Newton--Okounkov bodies of line bundles on a Bott--Samelson resolution of the complete flag variety of $GL_n$ for a geometric valuation coming from a flag of translated Schubert subvarieties. The Bott--Samelson resolution corresponds to the decomposition (s_1)(s_2s_1)(s_3s_2s_1)(...)(s_{n-1}\ldots s_1) of the longest element in the Weyl group, and the Schubert subvarieties correspond to the ...
Added: August 20, 2018