===== Pointwise function product ===== ==== Set ==== | @#55CCEE: context | @#55CCEE: $S$ ... set | | @#55CCEE: context | @#55CCEE: $\langle\!\langle M,* \rangle\!\rangle$ ... magma | | @#FF9944: definition | @#FF9944: $\star\in$ binary operation on $M^S$ | | @#FF9944: definition | @#FF9944: $(f\star g)(s):=f(s)*g(s)$ | ----- === Discussion === Extends to groups, etc. >the following could be phrased more explicitly. Note that $M^S$ can is just another notation for ${\mathrm{Hom}}_{\bf{Set}}(S,M)$. One of the main question of algebra is if a functor $F$ that maps into a a category of structures (like magmas) is representable, i.e. if there is a natural iso between $F$ and an internal [[Hom-functor]]. === Reference === Wikipedia: [[http://en.wikipedia.org/wiki/Pointwise_product|Pointwise product]], [[http://en.wikipedia.org/wiki/Magma_%28algebra%29|Magma]] ----- === Context === [[Magma]] === Subset of === [[Magma]] === Requirements* === [[Magma]]