28.11.2007 (Wednesday)

Representation theory and integrable spin chains

Exceptional Seminar Petr Kulish (St.Petersburg Department of Steklov Institute of Mathematics)

at:
15:00 City U.
room C345
abstract:

Solution of the Heisenberg spin chain s=1/2 (spectrum of the energy operator and its eigenvectors) is related with three algebras: the Lie algebra sl(2), group algebra of symmetric group S_N and an infinite dimentional Hopf algebra, Yangian Y(sl(2)). Using representaions of these algebras there are generalization of this model to higher spins s=1, 3/2, 2, ...However there is also possibility to geberalize these algebras preserving structure of their representations. In particular the group algebra of S_N will be substituted by the Temperle -- Lieb algebra.