Difference between revisions of "Functor"

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(Created page with "In mathematics, a '''functor''' is a type of mapping between categories which is applied in category theory. Functors can be thought of as Homomorphism|homomorphism...")
 
 
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== See also ==
 
== See also ==
  
* [[category theory]]
+
* [[Algebraic object]]
 +
* [[Algebraic topology]]
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* [[Category of small categories]]
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* [[Category theory]]
 
* [[Functor category]]
 
* [[Functor category]]
 
* [[Kan extension]]
 
* [[Kan extension]]
 
* [[Pseudofunctor]]
 
* [[Pseudofunctor]]
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* [[Topological space]]
  
 
== External links ==
 
== External links ==

Latest revision as of 10:02, 17 September 2016

In mathematics, a functor is a type of mapping between categories which is applied in category theory.

Functors can be thought of as homomorphisms between categories.

In the category of small categories, functors can be thought of more generally as morphisms.

Functors were first considered in algebraic topology, where algebraic objects (like the fundamental group) are associated to topological spaces, and algebraic homomorphisms are associated to continuous maps. Nowadays, functors are used throughout modern mathematics to relate various categories. Thus, functors are generally applicable in areas within mathematics that category theory can make an abstraction of.

The word functor was borrowed by mathematicians from the philosopher Rudolf Carnap, who used the term in a linguistic context.

See also

External links