搜索结果: 76-90 共查到“几何学其他学科”相关记录247条 . 查询时间(1.541 秒)
We investigate subdivisions of simplicial, cyclic, and dihedral sets by using Drinfeld’s expression of geometric realization as a filtered colimit.
We demonstrate the construction of several families of flexible polyhedra by extending Bricard octahedra to form larger composite flexible polyhedra. These flexible polyhedra are of genus 0 and 1, ha...
Our main result states that every fixed-point free continuous self-map of ${\mathbb R}^{n}$ is colorable. This result can be re-formulated as follows: A continuous map $f: {\mathbb R}^{n}\to {\mathbb...
Centro-Affine Invariants for Smooth Convex Bodies
Centro-Affine Invariants Smooth Convex Bodies
2010/11/24
Employing a centro-affine flow on smooth convex bodies, we generate new centro-affine differential invariants. One class of the newly defined invariants is the object of a sharp isoperimetric inequali...
On the heterochromatic number of hypergraphs associated to geometric graphs and to matroids
hypergraphs associated geometric graphs matroids
2010/11/24
The heterochromatic number hc(H) of a non-empty hypergraph H is the smallest integer k such that for every colouring of the vertices of H with exactly k colours, there is a hyperedge of H all of whos...
A curved Brunn--Minkowski inequality on the discrete hypercube
A curved Brunn--Minkowski inequality discrete hypercube
2010/11/24
We compare two approaches to Ricci curvature on non-smooth spaces, in the case of the discrete hypercube $\{0,1\}^N$. While the coarse Ricci curvature of the first author readily yields a positive va...
We use the CR geometry of the standard hyperquadric in complex projective three-space to give a detailed twistor description of conformal foliations in Euclidean three-space.
We study self-duality of Grothendieck's blended extensions (extensions panach\'ees) in the context of a tannakian category. The set of equivalence classes of symmetric, resp. antisymmetric, blended ex...
Solving a long-standing open question in convex geometry, we will show that typical convex surfaces contain points of infinite curvature in all tangent directions. To prove this, we use an easy curva...
On the dual of the mobile cone
the mobile cone math
2010/11/24
We prove that the cone of mobile divisors and the cone of curves birationally movable in codimension $1$ are dual in the $(K+B)$-negative part for a klt pair $(X/Z,B)$. We also prove the structure th...
We give a necessary and sufficient condition in order for a hyperplane arrangement to be of Torelli type, namely that it is recovered as the set of unstable hyperplanes of its Dolgachev sheaf of loga...
Matrices with restricted entries and q-analogues of permutations
Matrices q-analogues of permutations
2010/11/23
We study the functions that count matrices of given rank over a finite field with specified positions equal to zero. We show that these matrices are $q$-analogues of permutations with certain restrict...
Geometrization of principal series representations of GL_N associated to regular characters
Geometrization principal series representations
2010/11/23
In geometric representation theory, one often wishes to describe representations realized on spaces of invariant functions as trace functions of equivariant perverse sheaves. In the case of principal...
We revisit the relative perturbation theory for invariant subspaces of positive definite matrix pairs. As a prototype model problem for our results we consider parameter dependent families of eigenval...
McMullen's g-vector is important for simple convex polytopes. This paper postulates axioms for its extension to general convex polytopes. It also conjectures that, for each dimension d, a stated fini...