搜索结果: 46-60 共查到“几何学 geometry”相关记录125条 . 查询时间(0.116 秒)
Abstract: Cheeger's finiteness theorem bounds the number of diffeomorphism types of manifolds with bounded curvature, diameter and volume; the Hadamard--Cartan theorem, as popularized by Gromov, shows...
The Intrinsic Geometry of Almost Contact Metric Manifolds
almost contact manifold Sasakian manifold K-contact manifold the intrinsic geometry of almost contact metric manifolds
2011/9/22
Abstract: In this paper the notion of the intrinsic geometry of an almost contact metric manifold is introduced. Description of some classes of spaces with almost contact metric structures in terms of...
Orthogonal Basis and Motion in Finsler Geometry
Orthogonal Basis and Motion Finsler Geometry Differential Geometry
2011/9/20
Abstract: Finsler space is differentiable manifold for which Minkowski space is the fiber of the tangent bundle. To understand structure of the reference frame in Finsler space, we need to understand ...
On one class of holonomy groups in pseudo-Riemannian geometry
holonomy groups pseudo-Riemannian geometry Differential Geometry
2011/9/5
Abstract: We prove the following theorem. Let g be a nondegenerate bilinear form on a vector space V, and L:V -> V a g-symmetric operator. Then the centraliser of L in SO(g) is a holonomy group for a ...
Abstract: We propose a formulation of a Lorentzian quantum geometry based on the framework of causal fermion systems. After giving the general definition of causal fermion systems, we deduce space-tim...
Supergravity as Generalised Geometry I: Type II Theories
Supergravity Generalised Geometry I High Energy Physics - Theory
2011/9/30
Abstract: We reformulate ten-dimensional type II supergravity as a generalised geometrical analogue of Einstein gravity, defined by an $O(9,1)\times O(1,9)\subset O(10,10)\times\bbR^+$ structure on th...
Schrodinger equations, deformation theory and $tt^*$-geometry
Schrodinger equations deformation theory Differential Geometry
2011/8/26
Abstract: This is the first of a series of papers to construct the deformation theory of the form Schr\"odinger equation, which is related to a section-bundle system $(M,g,f)$, where $(M,g)$ is a nonc...
The geometry of embedded pseudo-Riemannian surfaces in terms of Poisson brackets
pseudo-Riemannian manifolds embedded surfaces Poisson brackets
2011/8/25
Abstract: Arnlind, Hoppe and Huisken showed how to express the Gauss and mean curvature of a surface embedded in a Riemannian manifold in terms of Poisson brackets of the embedding coordinates. We gen...
Abstract: This is a survey on the geometry of warped products, without, or essentially with only soft, calculation. Somewhere in the paper, the goal was to give a synthetic account since existing appr...
Basic coordinate-free non-Euclidean geometry
Basic coordinate-free non-Euclidean geometry Differential Geometry
2011/8/23
Abstract: These lecture notes are based on [arXiv: math/0702714, 0907.4469, 0907.4470]. We introduce and study basic aspects of non-Euclidean geometries from a coordinate-free viewpoint.
How Geometry Controls the Tearing of Adhesive Thin Films on Curved Surfaces
Geometry Controls Curved Surfaces Adhesive Thin Films Tearing
2011/7/7
Flaps can be detached from a thin film glued on a solid substrate by tearing and peeling. For flat substrates, it has been shown that these flaps spontaneously narrow and collapse in pointy triangular...
Exceptional collections on toric Fano threefolds and birational geometry
Exceptional collections toric Fano threefolds birational geometry
2011/2/22
Bernardi and Tirabassi show the existence of a full strong excep-tional collection consisting of line bundles on smooth toric Fano 3-folds under assuming Bondal’s conjecture, which states that the Fro...
In a holomorphic family (Xb)b∈B of non-K¨ahlerian compact manifolds,the holomorphic curves representing a fixed 2-homology class do not form a proper family in general.
Gauge fixing in (2+1)-gravity: Dirac bracket and spacetime geometry
Gauge fixing (2+1)-gravity: Dirac bracket spacetime geometry
2011/3/2
We consider (2+1)-gravity with vanishing cosmological constant as a constrained dynamical system. By applying Dirac’s gauge fixing procedure, we implement the constraints and determine the Dirac brack...
Line bundles and the Thom construction in noncommutative geometry
Line bundles Thom construction noncommutative geometry
2011/1/19
The idea of a line bundle in classical geometry is transferred to noncommutative geometry by the idea of a Morita context. From this we can construct Z and N graded algebras, the Z graded algebra bein...