commutator calculus

  • 21Free Lie algebra — In mathematics, a free Lie algebra, over a given field K, is a Lie algebra generated by a set X, without any imposed relations. Contents 1 Definition 2 Universal enveloping algebra 3 Hall sets …

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  • 22Nichols algebra — The Nichols algebra of a braided vector space (with the braiding often induced by a finite group) is a braided Hopf algebra which is denoted by and named after the mathematician Warren Nichols. It takes the role of quantum Borel part of a pointed …

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