Speaker
Prof.
Leonid Glozman
(University of Graz)
Description
Mesons constructed from the quark propagators without the lowest-lying eigenmodes of the Dirac operator reveal not only restored chiral and U(1)_A symmetries, but actually a higher symmetry. All possible
chiral and U(1)_A multiplets for the states of the same spin are degenerate, i.e. the energy of the
observed quantum levels does not depend on the spin orientation of quarks and their parities. The quark-spin
independence of the energy levels implies absence of the magnetic interactions in the system. The ultrarelativistic quark-antiquark system with only the color-electric interactions can be interpreted
(or defined) as a dynamical QCD string. The symmetry group of the J>=1 levels of the string is SU(4).
Author
Prof.
Leonid Glozman
(University of Graz)
