Search results
Results From The WOW.Com Content Network
The tangent bundle comes equipped with a natural topology (not the disjoint union topology) and smooth structure so as to make it into a manifold in its own right. The dimension of is twice the dimension of . Each tangent space of an n-dimensional manifold is an n-dimensional vector space
The definitions of the tangent bundle, the unit tangent bundle and the (oriented orthonormal) frame bundle F can be extended to arbitrary surfaces in the usual way. [7] [15] There is a similar identification between the latter two which again become principal SO(2)-bundles. In other words: The frame bundle is a principal bundle with structure ...
In mathematics, a projective bundle is a fiber bundle whose fibers are projective spaces. By definition, a scheme X over a Noetherian scheme S is a P n -bundle if it is locally a projective n -space; i.e., X × S U ≃ P U n {\displaystyle X\times _{S}U\simeq \mathbb {P} _{U}^{n}} and transition automorphisms are linear.
The choice of a projective embedding of X, modulo projective transformations is likewise equivalent to the choice of a very ample line bundle on X. A morphism to a projective space : defines a globally generated line bundle by () and a linear system
The tangent space of at , denoted by , is then defined as the set of all tangent vectors at ; it does not depend on the choice of coordinate chart :. The tangent space T x M {\displaystyle T_{x}M} and a tangent vector v ∈ T x M {\displaystyle v\in T_{x}M} , along a curve traveling through x ∈ M {\displaystyle x\in M} .
In Euclidean 3-space, a plane containing the origin is completely characterized by the one and only line through the origin that is perpendicular to that plane (and vice versa); hence the spaces Gr(2, 3), Gr(1, 3), and P 2 (the projective plane) may all be identified with each other. The simplest Grassmannian that is not a projective space is ...
which takes each point of the bundle to its base point. The fiber π −1 (x) over each point x ∈ M is an (n−1)-sphere S n−1, where n is the dimension of M. The unit tangent bundle is therefore a sphere bundle over M with fiber S n−1. The definition of unit sphere bundle can easily accommodate Finsler manifolds as well.
An ovoid in a 3-dimensional projective space is a set of points, which a) is intersected by lines in 0, 1, or 2 points and b) its tangents at an arbitrary point covers a plane (tangent plane). The geometry of an ovoid in projective 3-space is a Möbius plane, called an ovoidal Möbius plane. The point set of the geometry consists of the points ...