Definition
Let X be a topological space and A a sheaf of rings on X. (In other words, (X, A) is a ringed space.) An ideal sheaf J in A is a subobject of A in the category of sheaves of A-modules, i.e., a subsheaf of A viewed as a sheaf of abelian groups such that
- Γ(U, A) · Γ(U, J) ⊆ Γ(U, J)
for all open subsets U of X.
Read more about this topic: Ideal Sheaf
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