Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,695 papers · 148 categories

Trend · papers per month

13253850 · May 202619922001200920172026
48 results for Affine Grassmannians

The affine Grassmannian is a noncompact smooth manifold that parameterizes all affine subspaces of a fixed dimension. It is a natural generalization of Euclidean space, points being zero-dimensional affine subspaces. We will realize the affine Grassmannian as a matrix manifold and extend Riemannian optimization algorit…

2016-07-06abs ↗pdf ↗

Correspondence found between exponential families and affine Grassmannians.

problem Understanding the relationship between exponential families and geometric structures.
method Established a one-to-one correspondence between exponential families and affine Grassmannians.
result Found a correspondence between minimal exponential families and affine Grassmannians.

The Grassmannian of affine subspaces is a natural generalization of both the Euclidean space, points being zero-dimensional affine subspaces, and the usual Grassmannian, linear subspaces being special cases of affine subspaces. We show that, like the Grassmannian, the affine Grassmannian has rich geometrical and topolo…

2018-07-28abs ↗pdf ↗

The classical concept of affine locally symmetric spaces allows a generalization for various geometric structures on a smooth manifold. We remind the notion of symmetry for parabolic geometries and we summarize the known facts for 1|1|--graded parabolic geometries and for almost Grassmannian structures, in particular.…

2009-01-07abs ↗pdf ↗

The paper studies a special Grassmannian space and shows it's an orbit of a unitary group.

problem Investigating a specific Grassmannian space of infinite-dimensional subspaces.
method Analyzing the restricted pp-Schatten class Grassmannian and showing it's an affine coadjoint orbit of a unitary group.
result The restricted pp-Schatten class Grassmannian is shown to be an affine coadjoint orbit of an infinite-dimensional restricted unitary group.

This is a companion paper of arXiv:1601.03586. We study Coulomb branches of unframed and framed quiver gauge theories of type ADEADE. In the unframed case they are isomorphic to the moduli space of based rational maps from CP1{\mathbb C}P^1 to the flag variety. In the framed case they are slices in the affine Grassmannia…

2016-04-13abs ↗pdf ↗

The paper introduces exponential-wrapped distributions on symmetric spaces for better data modeling.

problem Challenges in statistical modeling due to curvature of data spaces.
method Construction and use of exponential-wrapped distributions on affine locally symmetric spaces.
result Exponential-wrapped distributions on symmetric spaces have useful properties for practical use.

This is the third companion paper of arXiv:1601.03586. When a gauge theory has a flavor symmetry group, we construct a partial resolution of the Coulomb branch as a variant of the definition. We identify the partial resolution with a partial resolution of a generalized slice in the affine Grassmannian, Hilbert scheme o…

2018-05-30abs ↗pdf ↗

Using the Penrose transform, we construct analogues of the BGG (Bernstein-Gelfand-Gelfand) resolutions in certain singular infinitesimal characters, in the holomorphic geometric setting, over the Lagrangian Grassmannian. We prove the exactness of the constructed complex over the big affine cell.

2017-11-13abs ↗pdf ↗

Let G be a simple algebraic group. Labelled trivalent graphs called webs can be used to product invariants in tensor products of minuscule representations. For each web, we construct a configuration space of points in the affine Grassmannian. Via the geometric Satake correspondence, we relate these configuration spaces…

2011-03-17abs ↗pdf ↗

We construct a model space $C(\gsp(\bR^{2n}))$ for the variety of Abelian simply transitive groups of affine transformations of type ${\rm Sp}(\bR^{2n})$. The model is stratified and its principal stratum is a Zariski-open subbundle of a natural vector bundle over the Grassmannian of Lagrangian subspaces in $\bR^{2n}$.…

2001-05-03abs ↗pdf ↗

Develops a method to construct entire minimal graphs of odd dimensions.

problem Constructing entire minimal graphs of odd dimensions and arbitrary codimensions.
method Evolving-plane ansatz reducing minimal surface system to geodesic equation on Grassmannian.
result Yields a rich family of explicit entire minimal graphs of odd dimension and arbitrary codimension.

We develop an integral geometry of stationary Euler equations defining some function ww on the Grassmannian of affine lines in the space. This function depends on a putative compactly supported solution vv of the system, and we deduce a linear differential equation for ww. We prove also that the purported annulation…

2016-08-31abs ↗pdf ↗

GDMaps reduces high-dimensional data to lower dimensions for better classification.

problem High-dimensional data classification and representation.
method Grassmannian Diffusion Maps technique for nonlinear dimensionality reduction.
result GDMaps effectively identifies intrinsic subspace structures in high-dimensional data.

Positive configurations of points in the affine building were introduced in \cite{Le} as the basic object needed to define higher laminations. We start by giving a self-contained, elementary definition of positive configurations of points in the affine building and their basic properties. Then we study the geometry of …

2015-10-31abs ↗pdf ↗

Curious structure of special orthogonal, unitary, and symplectic groups as products of Grassmannians discovered.

problem Understanding the structure of special orthogonal, unitary, and symplectic groups.
method Expressing these groups as products of Grassmannians realized as involution matrices.
result Special orthogonal, special unitary, and symplectic groups can be expressed as products of their corresponding Grassmannians.

Constructs explicit pp-harmonic functions on Grassmannians and flag manifolds.

problem Finding proper pp-harmonic functions on Grassmannians and flag manifolds.
method Using the method of eigenfamilies to construct explicit functions.
result Explicit complex-valued proper pp-harmonic functions on compact real Grassmannians and non-descending functions on real flag manifolds.

Using the Plucker map between grassmannians, we study basic aspects of classic grassmannian geometries. For `hyperbolic' grassmannian geometries, we prove some facts (for instance, that the Plucker map is a minimal isometric embedding) that were previously known in the `elliptic' case.

2009-07-26abs ↗pdf ↗

The paper classifies real hypersurfaces with a specific Jacobi operator in complex Grassmannians.

problem Classifying real hypersurfaces with a particular Jacobi operator.
method Introducing and classifying real hypersurfaces with a quadratic Killing structure Jacobi operator.
result A classification theorem for Hopf real hypersurfaces with quadratic Killing structure Jacobi operator.

Smooth structures on infinite dimensional Grassmannians and non-commutative cross-ratios.

problem Smooth structures on infinite dimensional Grassmannians and non-commutative cross-ratios.
method Analyzing and expanding the notion of non-commutative cross-ratios, proving their smoothness.
result Smoothness of non-commutative cross-ratios.

This paper proves area-minimizing cones over Grassmannian manifolds.

problem Determine if cones over Grassmannian manifolds are area-minimizing.
method Detailed descriptions of embedding maps using Hermitian orthogonal projectors, re-proving area-minimization using Lawlor's Curvature Criterion.
result All cones over Grassmannian manifolds are area-minimizing except for oriented real Grassmannians.

Develops a correspondence between symplectic orbits and Grassmannians.

problem Understanding the homotopy types of Grassmannians of linear subspaces in symplectic vector spaces.
method Uses orbit fibrations and linear symplectic reduction to compute homotopy types.
result Recover observations from Arnold, Oh-Park, and Lee-Leung in different cases.

This paper contains a thorough introduction to the basic geometric properties of the manifold of Lagrangian subspaces of a linear symplectic space, known as the Lagrangian Grassmannian. It also reviews the important relationship between hypersurfaces in the Lagrangian Grassmannian and second-order PDEs.

2018-05-11abs ↗pdf ↗

There is a natural filtration on the space of degree-kk homogeneous polynomials in nn independent variables with coefficients in the algebra of smooth functions on the Grassmannian Gr(n,s)\mathrm{Gr}(n,s), determined by the tautological bundle. In this paper we show that the space of ss-dimensional integral elements of a…

2012-08-29abs ↗pdf ↗

Reformulated sigma models for complex Grassmannians using Gross-Neveu formalism.

problem Classical aspects of N=(2,2)\mathcal{N}=(2,2) supersymmetric sigma models with Hermitian symmetric target spaces.
method Reformulation using Gross-Neveu formalism, proposing two types of equivalent Lagrangians.
result Proposed two types of equivalent Lagrangians for maximal isotropic Grassmannians, making either supersymmetry or geometry manifest.

Study cohomology rings of Grassmannians using Clifford algebras and symmetric spaces.

problem Understanding cohomology rings of Grassmannians over different fields.
method Explicit generators and relations for de Rham cohomology rings, filtered deformations related to Clifford algebras.
result Explicit generators and relations for the de Rham cohomology rings of Grassmannians.

In this paper, we study real hypersurfaces in complex Grassmannians of rank two. First, the nonexistence of mixed foliate real hypersurfaces is proven. With this result, we show that for Hopf hypersurfaces in complex Grassmannians of rank two, the Reeb principal curvature is constant along integral curves of the Reeb v…

2015-12-01abs ↗pdf ↗

Constructs explicit harmonic functions and morphisms on complex and quaternionic Grassmannians.

problem Creating explicit solutions for pp-harmonic functions and harmonic morphisms.
method Using joint eigenfunctions of the Laplace-Beltrami and conformality operators.
result Induces solutions on dual non-compact Riemannian symmetric spaces.