In mathematics, one can often define a direct product of objects already known, giving a new one. This is generally the Cartesian product of the underlying sets, together with a suitably defined structure on the product set. More abstractly, one talks about the product in category theory, which formalizes these notions.
Examples are the product of sets (see Cartesian product), groups (described below), the product of rings and of other algebraic structures. The product of topological spaces is another instance.
There is also the direct sum – in some areas this is used interchangeably, in others it is a different concept.
Read more about Direct Product: Examples, Group Direct Product, Direct Product of Modules, Topological Space Direct Product, Direct Product of Binary Relations, Categorical Product, Internal and External Direct Product, Metric and Norm
Famous quotes containing the words direct and/or product:
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