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Results tagged with ac.commutative-algebra
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user 98863
Commutative rings, modules, ideals, homological algebra, computational aspects, invariant theory, connections to algebraic geometry and combinatorics.
5
votes
Direct sum of Hopf algebras
This is a positive version of the answer "no".
As already mentioned before, the disjoint union of groups is not a group, BUT it is a grupoid!
In a similar way, the direct sum of two Hopf algebras is n …
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