Module theory MOC
Submodule
Let (𝑀,𝑅, +, ⋅) be a (left) module.
A submodule 𝑁 ≤𝑀 is a module under the same operations, #m/def/module
i.e. (𝑁, +) is a subgroup such that 𝑟 ⋅𝑛 ∈𝑁 for any 𝑛 ∈𝑁 and 𝑟 ∈𝑅.
Thus a submodule is an invariant subspace under the carried representation of 𝑅 (see invariant subspace).
Examples
- Let 𝐼 ⊴𝑅 be an ideal. Then 𝐼 is an 𝑅-submodule of 𝑅.
#state/tidy | #lang/en | #SemBr