Connected ring

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In mathematics, especially in the field of commutative algebra, a connected ring is a commutative ring A that satisfies one of the following equivalent conditions: [1]

Contents

Examples and non-examples

Connectedness defines a fairly general class of commutative rings. For example, all local rings and all (meet-)irreducible rings are connected. In particular, all integral domains are connected. Non-examples are given by product rings such as Z × Z; here the element (1, 0) is a non-trivial idempotent.

Generalizations

In algebraic geometry, connectedness is generalized to the concept of a connected scheme.

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