Contatto di riferimento: Barbara Simoni
Partecipanti: Prof. Nepomechie Raphael (Universita' di Miami, USA)
Abstract: Integrable quantum spin chains are of fundamental importance in theoretical physics. While both bulk and boundary phenomena are important, the latter are often more complicated, and are therefore less well understood. This talk will review some recent progress on the boundary problem. After recalling basic ideas of quantum integrability, the "off-diagonal Bethe ansatz" approach will be explained, using the isotropic (XXX) Heisenberg chain with non-diagonal boundary terms as the working example. This technique will then be applied to a boundary problem in AdS/CFT, corresponding to an open string attached at one end to a Y=0 brane, and at the other end to a Y_\theta=0 brane, which is rotated with respect to the former by an arbitrary angle \theta.