[For the entire collection see Zbl 0742.00067.]Let be the Lie algebra , and let be the universal enveloping algebra for . Let be the center of . The authors consider the chain of Lie algebras . Then is an associative algebra which is called the Gel’fand-Zetlin subalgebra of . A module is called a -module if , where the summation is over the space of characters of and , , . The authors describe several properties of - modules. For example, they prove that if for some and the module is simple, then is a -module. Indecomposable - modules are also described. The authors give three conjectures on - modules and!
@article{701487, title = {On Gelfand-Zetlin modules}, booktitle = {Proceedings of the Winter School "Geometry and Physics"}, series = {GDML\_Books}, publisher = {Circolo Matematico di Palermo}, address = {Palermo}, year = {1991}, pages = {[143]-147}, mrnumber = {MR1151899}, zbl = {0754.17005}, url = {http://dml.mathdoc.fr/item/701487} }
Drozd, Yu. A.; Ovsienko, S. A.; Futorny, V. M. On Gelfand-Zetlin modules, dans Proceedings of the Winter School "Geometry and Physics", GDML_Books, (1991), pp. [143]-147. http://gdmltest.u-ga.fr/item/701487/