Morphisms | Ring theory

Ring homomorphism

In ring theory, a branch of abstract algebra, a ring homomorphism is a structure-preserving function between two rings. More explicitly, if R and S are rings, then a ring homomorphism is a function f : R → S such that f is: addition preserving: for all a and b in R,multiplication preserving: for all a and b in R,and unit (multiplicative identity) preserving:. Additive inverses and the additive identity are part of the structure too, but it is not necessary to require explicitly that they too are respected, because these conditions are consequences of the three conditions above. If in addition f is a bijection, then its inverse f−1 is also a ring homomorphism. In this case, f is called a ring isomorphism, and the rings R and S are called isomorphic. From the standpoint of ring theory, isomorphic rings cannot be distinguished. If R and S are rngs, then the corresponding notion is that of a rng homomorphism, defined as above except without the third condition f(1R) = 1S. A rng homomorphism between (unital) rings need not be a ring homomorphism. The composition of two ring homomorphisms is a ring homomorphism. It follows that the class of all rings forms a category with ring homomorphisms as the morphisms (cf. the category of rings).In particular, one obtains the notions of ring endomorphism, ring isomorphism, and ring automorphism. (Wikipedia).

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Homomorphisms in abstract algebra

In this video we add some more definition to our toolbox before we go any further in our study into group theory and abstract algebra. The definition at hand is the homomorphism. A homomorphism is a function that maps the elements for one group to another whilst maintaining their structu

From playlist Abstract algebra

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From playlist Abstract Algebra

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From playlist Abstract Algebra

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A lecture on Ring Homomorphisms.

From playlist Modern Algebra

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From playlist Abstract algebra

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This project was created with Explain Everything™ Interactive Whiteboard for iPad.

From playlist Modern Algebra

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From playlist Abstract Algebra

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From playlist Visual Group Theory

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From playlist Algebraic geometry II: Schemes

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From playlist Abstract algebra

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From playlist Algebraic geometry II: Schemes

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From playlist Abstract Algebra

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From playlist Abstract Algebra

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From playlist HIM Lectures 2015

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From playlist Modern Algebra - Chapter 17 (group homomorphisms)

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