new vector spaces from old ones
This entry list methods that give new vector spaces from old ones.
- 1.
Changing the field (complexification
, etc.)
- 2.
vector subspace
- 3.
Quotient vector space
- 4.
direct product
of vectors spaces
- 5.
Cartesian product of vector spaces
- 6.
Tensor product
of vector spaces (http://planetmath.org/TensorProductClassical)
- 7.
The space of linear maps from one vector space to another, also denoted by , or simply , where and are vector spaces over the field
- 8.
The space of endomorphisms
of a vector space. Using the notation above, this is the space
- 9.
dual vector space (http://planetmath.org/DualSpace), and bi-dual vector space. Using the notation above, this is the space , or simply .
- 10.
The annihilator
of a subspace
is a subspace of the dual vector space
- 11.
Wedge product
of vector spaces
- 12.
A field is a vector space over itself. Consider a set and the set of all functions from to . Then has a natural vector space structure. If is finite, then can be viewed as a vector space having as a basis.
Vector spaces involving a linear map
Suppose is a linear map.
- 1.
The kernel of is a subspace of .
- 2.
The image of is a subspace of .
- 3.
The cokernel
of is a quotient space
of .
Topological vector spaces
Suppose is topological vector space.
- 1.
If is a subspace of then its closure
is also a subspace of .
- 2.
If is a metric vector space then its completion is also a (metric) vector space.
- 3.
The direct integral of Hilbert spaces provides a new Hilbert space
.
Spaces of structures and subspaces of the tensor algebra of a vector space
There are also certain spaces of interesting structures on a vectorspace that at least in the case of finite dimension correspond tocertain subspaces of the tensor algebra of the vector space. Thesespaces include:
- 1.
The space of Euclidean inner products
.
- 2.
The space of Hermitian inner products.
- 3.
the space of symplectic structures.
- 4.
vector bundles
- 5.
space of connections