Skip to content

Tag

Direct Product

5 resources tagged “Direct Product” across the knowledge library.

5 items

Guide6 Aug 2026Cohomology of Products and Coproducts of GroupsCohomology of a direct product via Kunneth, cohomology of a free product as a direct sum, Mayer-Vietoris for amalgamated products, and the contrast between the two constructions.3 min readRead More Guide6 Aug 2026Direct Products, Factor Congruences and Direct IndecomposabilityDirect products, projection homomorphisms, factor congruences as the internal signature of a decomposition, directly indecomposable algebras and the limits of unique factorisation.4 min readRead More Guide6 Aug 2026Direct Sums, Products and Split SequencesDirect sums and direct products of modules, their universal properties, the splitting lemma and equivalent characterisations of split short exact sequences.4 min readRead More Guide6 Aug 2026Directly Representable VarietiesDirectly representable varieties, McKenzie's theorem that they are congruence-permutable, the classification of their directly indecomposable members, and the connection to the (discriminator) ⊗ (modular Abelian) decomposition.5 min readRead More Guide6 Aug 2026Skew-free AlgebrasSkew congruences in direct products, skew-free algebras and varieties, the relationship to congruence permutability and distributivity, and the role in Boolean representations.5 min readRead More