Results 11 to 20 of about 41 (41)
Grassmanniennes affines tordues sur les entiers
Forum of Mathematics, Sigma, 2023 We generalize the works of Pappas–Rapoport–Zhu on twisted affine Grassmannians to the wildly ramified case under mild assumptions. This rests on a construction of certain smooth affine $\mathbb {Z}[t]$ -groups with connected fibers of parahoric ...
João Lourenço
doaj +1 more source
Representation type via Euler characteristics and singularities of quiver Grassmannians
Bulletin of the London Mathematical Society, Volume 51, Issue 5, Page 815-835, October 2019., 2019 Abstract In this paper, we characterize the representation type of an acyclic quiver by the properties of its associated quiver Grassmannians. This characterization utilizes and extends known results about singular quiver Grassmannians and cell decompositions into affine spaces.
Oliver Lorscheid, Thorsten Weist
wiley +1 more source
Inverse K-Chevalley formulas for semi-infinite flag manifolds, I: minuscule weights in ADE type
Forum of Mathematics, Sigma, 2021 We prove an explicit inverse Chevalley formula in the equivariant K-theory of semi-infinite flag manifolds of simply laced type. By an ‘inverse Chevalley formula’ we mean a formula for the product of an equivariant scalar with a Schubert class, expressed
Takafumi Kouno +3 more
doaj +1 more source
Isometry Lie algebras of indefinite homogeneous spaces of finite volume
Proceedings of the London Mathematical Society, Volume 119, Issue 4, Page 1115-1148, October 2019., 2019 Abstract Let g be a real finite‐dimensional Lie algebra equipped with a symmetric bilinear form ⟨·,·⟩. We assume that ⟨·,·⟩ is nil‐invariant. This means that every nilpotent operator in the smallest algebraic Lie subalgebra of endomorphisms containing the adjoint representation of g is an infinitesimal isometry for ⟨·,·⟩.
Oliver Baues +2 more
wiley +1 more source
Convexity of tableau sets for type A Demazure characters (key polynomials), parabolic Catalan numbers [PDF]
Discrete Mathematics & Theoretical Computer Science, 2018 This is the first of three papers that develop structures which are counted by a "parabolic" generalization of Catalan numbers. Fix a subset R of {1,..,n-1}. Consider the ordered partitions of {1,..,n} whose block sizes are determined by R. These are the
Robert A. Proctor, Matthew J. Willis
doaj +1 more source
On fuzzy subbundles of vector bundles
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 40, Page 2553-2565, 2003., 2003 This paper considers fuzzy subbundles of a vector bundle. We define the operations sum, product, tensor product, Hom, and intersection of fuzzy subbundles and in each case, we characterize the corresponding flag of vector subbundles. We then propose two alternative definitions of integrability on fuzzy subbundles of a given type and discuss their ...
V. Murali, G. Lubczonok
wiley +1 more source
Parabolic Catalan numbers count flagged Schur functions and their appearances as type A Demazure characters (key polynomials) [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 Fix an integer partition lambda that has no more than n parts. Let beta be a weakly increasing n-tuple with entries from {1,..,n}. The flagged Schur function indexed by lambda and beta is a polynomial generating function in x_1, .., x_n for certain ...
Robert A. Proctor, Matthew J. Willis
doaj +1 more source
Equivalence classes of the 3 rd Grassman space over a 5‐dimensional vector space
International Journal of Mathematics and Mathematical Sciences, Volume 1, Issue 3, Page 297-305, 1978., 1978 An equivalence relation is defined on ΛrV, the rth Grassman space over V and the problem of the determnation of the equivalence classes defined by this relation is considered. For any r and V, the decomposable elements form an equivalence class. For r = 2, the length of the element determines the equivalence class that it is in.
Kuldip Singh
wiley +1 more source
Cluster Structures on Double Bott–Samelson Cells
Forum of Mathematics, Sigma, 2021 Let $\mathsf {C}$ be a symmetrisable generalised Cartan matrix. We introduce four different versions of double Bott–Samelson cells for every pair of positive braids in the generalised braid group associated to $\mathsf {C}$ .
Linhui Shen, Daping Weng
doaj +1 more source
Linear difference equations, frieze patterns, and the combinatorial Gale transform
Forum of Mathematics, Sigma, 2014 We study the space of linear difference equations with periodic coefficients and (anti)periodic solutions. We show that this space is isomorphic to the space of tame frieze patterns and closely related to the moduli space of configurations of points in ...
SOPHIE MORIER-GENOUD +3 more
doaj +1 more source