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Related papers: The Poisson degeneracy locus of a flag variety

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Given a compact oriented surface, we classify log Poisson bi-vectors whose degeneracy loci are locally modeled by a finite set of lines in the plane intersecting at a point. Further, we compute the Poisson cohomology of such structures and…

Symplectic Geometry · Mathematics 2018-09-12 Melinda Lanius

The two best studied toric degenerations of the flag variety are those given by the Gelfand--Tsetlin and FFLV polytopes. Each of them degenerates further into a particular monomial variety which raises the problem of describing the…

Algebraic Geometry · Mathematics 2024-02-28 Evgeny Feigin , Igor Makhlin

Dirac submanifolds are a natural generalization in the Poisson category for symplectic submanifolds of a symplectic manifold. In a certain sense they correspond to symplectic subgroupoids of the symplectic groupoid of the given Poisson…

Symplectic Geometry · Mathematics 2016-09-07 Ping Xu

It is shown that every $2$-shifted Poisson structure on a finitely generated semi-free commutative differential graded algebra $A$ defines a very explicit infinitesimal $2$-braiding on the homotopy $2$-category of the symmetric monoidal…

Quantum Algebra · Mathematics 2025-03-19 Cameron Kemp , Robert Laugwitz , Alexander Schenkel

While the intersection of the Grassmannian Bruhat decompositions for all coordinate flags is an intractable mess, the intersection of only the {\em cyclic shifts} of one Bruhat decomposition turns out to have many of the good properties of…

Algebraic Geometry · Mathematics 2009-03-24 Allen Knutson , Thomas Lam , David E Speyer

In this paper, we study invariant Poisson structures on homogeneous manifolds, which serve as a natural generalization of homogeneous symplectic manifolds previously explored in the literature. Our work begins by providing an algebraic…

Differential Geometry · Mathematics 2025-04-10 Abdelhak Abouqateb , Charif Bourzik

Recantly, William Crawley-Boevey proposed the definition of a Poisson structure on a noncommutative algebra $A$ based on the Kontsevich principle. His idea was to find the {\it weakest} possible structure on $A$ that induces standard…

Quantum Algebra · Mathematics 2012-02-14 Yuri Berest , Xiaojun Chen , Farkhod Eshmatov , Ajay Ramadoss

We prove that the connection vector fields associated to ample Poisson line bundles are not locally hamiltonian unless the Poisson structure is zero. We use this result to provide further evidence on Bondal's conjecture regarding the…

Algebraic Geometry · Mathematics 2026-04-09 Darío Aza

In this paper, we study formal deformations of Poisson structures, especially for three families of Poisson varieties in dimensions two and three. For these families of Poisson structures, using an explicit basis of the second Poisson…

Quantum Algebra · Mathematics 2008-11-13 Anne Pichereau

We introduce a Lie bialgebra structure on the central extension of the Lie algebra of differential operators on the line and the circle (with scalar or matrix coefficients). This defines a Poisson--Lie structure on the dual group of…

High Energy Physics - Theory · Physics 2009-10-22 Boris Khesin , Ilya Zakharevich

In the framework of the problem of characterizing complete flag manifolds by their contractions, the complete flags of type $F_4$ and $G_2$ satisfy the property that any possible tower of Bott-Samelson varieties dominating them birationally…

Algebraic Geometry · Mathematics 2022-02-24 Gianluca Occhetta , Luis E. Solá Conde

We give a construction of a Poisson transform mapping density valued differential forms on generalized flag manifolds to differential forms on the corresponding Riemannian symmetric spaces, which can be described entirely in terms of finite…

Differential Geometry · Mathematics 2017-01-25 Christoph Harrach

Let $V$ be a symplectic space over $\mathbb{C}$, $dim_\mathbb{C} V=2l$, and let $G$ be a finite subgroup of $Sp(V)$. The invariant regular functions $\mathbb{C}[V]^G$ inherit a Poisson algebra structure and so the quotient variety ${\cal…

Rings and Algebras · Mathematics 2007-07-09 Jacques Alev , Loïc Foissy

Poisson structures vanishing linearly on a set of smooth closed disjoint curves are generic in the set of all Poisson structures on a compact connected oriented surface. We construct a complete set of invariants classifying these structures…

Symplectic Geometry · Mathematics 2007-05-23 Olga Radko

We determine the fundamental groups of symmetrizable algebraically simply connected split real Kac-Moody groups endowed with the Kac-Peterson topology. In analogy to the finite-dimensional situation, the Iwasawa decomposition $G = KAU_+$…

Group Theory · Mathematics 2021-06-10 Paula Harring , Ralf Köhl

Poisson structures of divisor-type are those whose degeneracy can be captured by a divisor ideal, which is a locally principal ideal sheaf with nowhere-dense quotient support. This is a large class of Poisson structures which includes all…

Symplectic Geometry · Mathematics 2018-11-13 Ralph L. Klaasse

The degenerate Lie group is a semidirect product of the Borel subgroup with the normal abelian unipotent subgroup. We introduce a class of the highest weight representations of the degenerate group of type A, generalizing the PBW-graded…

Representation Theory · Mathematics 2012-02-29 Evgeny Feigin

We define Poisson structures on certain transversal slices to conjugacy classes in complex simple algebraic groups introduced in arXiv:0809.0205. These slices are associated to the elements of the Weyl group, and the Poisson structures on…

Representation Theory · Mathematics 2014-07-01 A. Sevostyanov

We study the problem of classifying all Poisson-Lie structures on the group $G_{\infty}$ of formal diffeomorphisms of the real line $\zR^{1}$ which leave the origin fixed, as well as the extended group of diffeomorphisms $G_{0\infty}\supset…

q-alg · Mathematics 2008-02-03 Ognyan Stoyanov

Given a split simply connected and connected algebraic group scheme $\mathbb G$ over $\mathbb Z$ and a split parabolic subgroup scheme $\mathbb P\subset \mathbb G$, this paper constructs semi-orthogonal decompositions of the bounded derived…

Algebraic Geometry · Mathematics 2026-05-28 Alexander Samokhin , Wilberd van der Kallen