English
Related papers

Related papers: Generic pipe dreams, lower-upper varieties, and Sc…

200 papers

Involution Schubert polynomials represent cohomology classes of $K$-orbit closures in the complete flag variety, where $K$ is the orthogonal or symplectic group. We show they also represent $T$-equivariant cohomology classes of subvarieties…

Combinatorics · Mathematics 2022-11-09 Zachary Hamaker , Eric Marberg , Brendan Pawlowski

Schubert polynomials are polynomial representatives of Schubert classes in the cohomology of the complete flag variety and have a combinatorial formulation in terms of bumpless pipe dreams. Quantum double Schubert polynomials are polynomial…

Combinatorics · Mathematics 2025-02-12 Tuong Le , Shuge Ouyang , Leo Tao , Joseph Restivo , Angelina Zhang

In [KU23] were introduced hybrid pipe dreams interpolating between classic and bumpless pipe dreams, each hybridization giving a different formula for double Schubert polynomials. A bijective proof was given (following [GH23]) of the…

Combinatorics · Mathematics 2025-09-03 Allen Knutson , Paul Zinn-Justin

In the space of equioriented type $A$ quiver representations, we define subvarieties called "open quiver loci" by placing strict rank conditions on the maps within representations. The closures of these subvarieties are the quiver loci,…

Combinatorics · Mathematics 2026-05-25 Moriah Elkin

In their study of infinite flag varieties, Lam, Lee, and Shimozono (2021) introduced bumpless pipe dreams in a new combinatorial formula for double Schubert polynomials. These polynomials are the TxT-equivariant cohomology classes of matrix…

Combinatorics · Mathematics 2025-09-03 Patricia Klein , Anna Weigandt

We give a new proof that three families of polynomials coincide: the double Schubert polynomials of Lascoux and Sch\"utzenberger defined by divided difference operators, the pipe dream polynomials of Bergeron and Billey, and the equivariant…

Combinatorics · Mathematics 2022-02-08 Allen Knutson

Schubert polynomials are distinguished representatives of Schubert cycles in the cohomology of the flag variety. In the spirit of Bergeron and Sottile, we use the Bruhat order to give $(n-1)!$ different combinatorial formulas for the…

Combinatorics · Mathematics 2024-07-09 Tianyi Yu

Knutson and Miller (2005) established a connection between the anti-diagonal Gr\"obner degenerations of matrix Schubert varieties and the pre-existing combinatorics of pipe dreams. They used this correspondence to give a…

Commutative Algebra · Mathematics 2023-01-19 Patricia Klein

We give bijective proofs of Monk's rule for Schubert and double Schubert polynomials computed with bumpless pipe dreams. In particular, they specialize to bijective proofs of transition and cotransition formulas of Schubert and double…

Combinatorics · Mathematics 2020-10-29 Daoji Huang

We develop a family of new combinatorial models for key polynomials. It is similar to the hybrid pipe dream model for Schubert polynomials defined recently by Knutson and Udell.

Combinatorics · Mathematics 2025-10-15 Yihan Xiao , Rui Xiong , Haofeng Zhang

In this paper, we establish a new geometric setting for bumpless pipe dreams and double Schubert polynomials. Building on the notion of bumpless pipe dream fragments, we define clan polynomials as their weight generating functions. It turns…

Combinatorics · Mathematics 2025-11-25 Yiming Chen , Neil J. Y. Fan , Rui Xiong , Ming Yao

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 of a classical group. We provide a combinatorial description for…

Combinatorics · Mathematics 2022-09-15 Evgeny Smirnov , Anna Tutubalina

The main goal of this paper is to extend two fundamental combinatorial results in Schubert calculus on flag manifolds from equivariant cohomology and $K$-theory to equivariant elliptic cohomology. The foundations of elliptic Schubert…

Combinatorics · Mathematics 2025-10-07 Cristian Lenart , Rui Xiong , Changlong Zhong

Weighted enumeration of reduced pipe dreams (or rc-graphs) results in a combinatorial expression for Schubert polynomials. The duality between the set of reduced pipe dreams and certain antidiagonals has important geometric implications [A.…

Combinatorics · Mathematics 2008-05-27 Ning Jia , Ezra Miller

Knutson and Zinn-Justin recently found a puzzle rule for the expansion of the product $\mathfrak{G}_{u}(x,t)\cdot \mathfrak{G}_{v}(x,t)$ of two double Grothendieck polynomials indexed by permutations with separated descents. We establish…

Combinatorics · Mathematics 2025-10-15 Neil J. Y. Fan , Peter L. Guo , Rui Xiong

The geometric naturality of Schubert polynomials and their combinatorial pipe dream representations was established by Knutson and Miller (2005) via antidiagonal Gr\"obner degeneration of matrix Schubert varieties. We consider instead…

Combinatorics · Mathematics 2022-03-25 Zachary Hamaker , Oliver Pechenik , Anna Weigandt

In our previous work we have introduced an analogue of Robinson-Schensted-Knuth correspondence for Schubert calculus of the complete flag varieties. The objects inserted are certain biwords, the outcomes of insertion are bumpless pipe…

Combinatorics · Mathematics 2023-04-17 Daoji Huang , Pavlo Pylyavskyy

Extending results of Wyser, we determine formulas for the equivariant cohomology classes of closed orbits of certain families of spherical subgroups of $GL_n$ on the flag variety $GL_n/B$. Putting this together with a slight extension of…

Algebraic Geometry · Mathematics 2017-12-12 Mahir Bilen Can , Michael Joyce , Benjamin Wyser

Lascoux and Sch\"utzenberger introduced Schubert and Grothendieck polynomials to study the cohomology and K-theory of the complete flag variety. We present explicit combinatorial rules for expressing Grothendieck polynomials in the basis of…

Combinatorics · Mathematics 2025-06-10 Anna Weigandt

Pipedreams and bumpless pipedreams are two combinatorial models that compute double Grothendieck polynomials. While studying matrix Schubert varieties, Pechenik, Speyer, and Weigandt defined a permutation statistic$\mathsf{rajcode}(\cdot)$…

Combinatorics · Mathematics 2026-05-26 Xuanying Han , Sophie C. C. Sun
‹ Prev 1 2 3 10 Next ›