Some algebraic structures have more than one law of composition. These must be connected by some kind of distributive laws, else the separate laws of composition are simply independent structures on the same set. The most elementary algebraic structures of this kind are known as rings and fields, and by combining fields and abelian groups we create vector spaces [1–7].
For the rest of this book, vector spaces will never be far away. For example, Hilbert spaces are structured vector spaces that form the basis of quantum mechanics. Even in non-linear theories such as classical mechanics and general relativity there exist local vector spaces known as the tangent space at each point, which are needed to formulate the dynamical equations. It is hard to think of a branch of physics that does not use vector spaces in some aspect of its formulation.
Contents
- 3.1 Rings and fields
- 3.2 Vector spaces
- 3.3 Vector space homomorphisms
- 3.4 Vector subspaces and quotient spaces
- 3.5 Bases of a vector space
- 3.6 Summation convention and transformation of bases
- 3.7 Dual spaces
Concept index
Terms by section. Links lead to the brown underlined definitions in the Chinese reading text.
3.1 Rings and fields
3.2 Vector spaces
3.3 Vector space homomorphisms
- linear map线性映射
- vector space homomorphism向量空间同态
- vector space isomorphism向量空间同构
- linear operator线性算符
- linear transformation线性变换
- general linear group一般线性群
3.4 Vector subspaces and quotient spaces
- vector subspace向量子空间
- complementary subspaces互补
- direct sum直和
- external direct sum外直和
- coset陪集
- quotient space商空间
- image像
- kernel核
- idempotent operator幂等算符
3.5 Bases of a vector space
- span张成或生成的子空间
- finite dimensional有限维
- infinite dimensional无限维
- dimension维数
- linearly independent线性无关
- basis基
- linearly dependent线性相关
- component分量
- codimension余维
3.6 Summation convention and transformation of bases
- summation convention求和约定
- dummy index哑指标
- bound index束缚指标
- free index自由指标
- Kronecker delta克罗内克符号
- contravariant逆变变换律
- passive transformation被动
- active transformation主动
- similarity transformation相似变换