Standard and nonstandard extensions of Lie algebras
نویسندگان
چکیده
منابع مشابه
Standard and Non-standard Extensions of Lie algebras
We study the problem of quadruple extensions of simple Lie algebras. We find that, adding a new simple root α+4, it is not possible to have an extended Kac-Moody algebra described by a Dynkin-Kac diagram with simple links and no loops between the dots, while it is possible if α+4 is a Borcherds imaginary simple root. We also comment on the root lattices of these new algebras. The folding proced...
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The present paper contains a systematic study of the structure of metric Lie algebras, i.e., finite-dimensional real Lie algebras equipped with a non-degenerate invariant symmetric bilinear form. We show that any metric Lie algebra g without simple ideals has the structure of a so called balanced quadratic extension of an auxiliary Lie algebra l by an orthogonal l-module a in a canonical way. I...
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It is well known that the standard bracketings of Lyndon words in an alphabet A form a basis for the free Lie algebra Lie(A) generated by A . Suppose that g 2 Lie(A)/J is a Lie algebra given by a generating set A and a Lie ideal J of relations. Using a Grobner basis type approach we define a set of "standard" Lyndon words, a subset of the set Lyndon words, such that the standard bracketings of ...
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ژورنال
عنوان ژورنال: Journal of Mathematical Physics
سال: 2006
ISSN: 0022-2488,1089-7658
DOI: 10.1063/1.2162128