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Topology/Morphisms
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Topology Morphisms Vector Spaces Convexity
In general, a morphism refers to a function mapping from one space to another that preserves structure. In terms of vector spaces the natural morphism is a linear map.
Linear maps
Definition of Linear Map
A linear map is a function where are vector spaces over a field F. Such that for all
1.
2.
The image of a linear map is a subspace of the domain. The kernel of a linear map is a subspace of the codomain.
The Importance of Kernels and Images
Definition of Rank
The rank of a linear map is the dimension of the image of the map . It also can be found using row reduction on the corresponding matrix.
Definition of Nullity
The nullity of a linear map, or matrix, is the dimension of the kernel of the map .
The Rank-Nullity Theorem
For any linear map
Topology Morphisms Vector Spaces Convexity