Direct Sum Of Modules
In abstract algebra, the direct sum is a construction which combines several modules into a new, larger module. The direct sum of modules is the smallest module which contains the given modules as submodules with no "unnecessary" constraints, making it an example of a coproduct. Contrast with the direct product, which is the dual notion.
The most familiar examples of this construction occur when considering vector spaces (modules over a field) and abelian groups (modules over the ring Z of integers). The construction may also be extended to cover Banach spaces and Hilbert spaces.
Read more about Direct Sum Of Modules: Construction For Vector Spaces and Abelian Groups, Construction For An Arbitrary Family of Modules, Properties, Internal Direct Sum, Universal Property, Grothendieck Group, Direct Sum of Modules With Additional Structure
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