Insights Lie Algebras: A Walkthrough - The Representations

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Frobenius began in ##1896## to generalize Weber's group characters and soon investigated homomorphisms from finite groups into general linear groups ##GL(V)##, supported by earlier considerations from Dedekind. Representation theory was born, and it developed fast in the following decades. The basic object of interest, however, has never been changed: A structure-preserving mapping from one class of objects into another which allows matrix representations.

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