Introduction to lie algebras and representation theory

By Vyjayanthi Chari and Andrew Pressley: 651 pp., £22.95 (US$34.95), isbn 0 521 55884 0 (Cambridge University Press, 1994).

A guide to quantum groups

Hom-algebra structures are given on linear spaces by multiplications twisted by linear maps. Hom-Lie algebras and general quasi-Hom-Lie and quasi-Lie algebras were introduced by Hartwig, Larsson and Silvestrov as algebras embracing Lie algebras, super and color Lie algebras and their quasi-deformations by twisted derivations. In this paper we introduce and study Hom-associative, Hom-Leibniz and Hom-Lie admissible algebraic structures generalizing associative, Leibniz and Lie admissible algebras. Also, we characterize flexible Hom-algebras and explain some connections and differences between Hom-Lie algebras and Santilli’s isotopies of associative and Lie algebras.

Hom-algebra structures

Quasi-hom-Lie algebras, central extensions and 2-cocycle-like identities

Classes of $G$-Hom-associative algebras are constructed as deformations of $G$-associative algebras along algebra endomorphisms. As special cases, we obtain Hom-associative and Hom-Lie algebras as deformations of associative and Lie algebras, respectively, along algebra endomorphisms. Chevalley-Eilenberg type homology for Hom-Lie algebras are also constructed.

Hom-algebras and homology

Deformations of Lie Algebras using σ-Derivations

http://www.math.chalmers.se/Math/Research/Preprints/2005/7.pdf

Locally finite simple weight modules over twisted generalized Weyl algebras

Multiparameter Twisted Weyl Algebras

Principal Galois orders and Gelfand-Zeitlin modules

It is shown that the q-difference Noether problem for all classical Weyl groups has a positive solution, simultaneously generalizing well known results on multisymmetric functions of Mattuck and Miyata in the case q=1, and q-deforming the noncommutative Noether problem for the symmetric group. It is also shown that the quantum Gelfand-Kirillov conjecture for gl_N (for a generic q) follows from the positive solution of the q-difference Noether problem for the Weyl group of type D_n. The proof is based on the theory of Galois rings developed by the first author and Ovsienko. From here we obtain a new proof of the quantum Gelfand-Kirillov conjecture for sl_N, thus recovering the result of Fauquant-Millet. Moreover, we provide an explicit description of skew fields of fractions for quantized gl_N and sl_N generalizing Alev and Dumas.

Jonas T. Hartwig

Papers

Deformations of Lie Algebras using σ-Derivations

Locally finite simple weight modules over twisted generalized Weyl algebras

Multiparameter Twisted Weyl Algebras

Principal Galois orders and Gelfand-Zeitlin modules

Solution of a q-difference Noether problem and the quantum Gelfand-Kirillov conjecture for gl_N