Infinite additional symmetries in two-dimensional conformal quantum field theory

Additional symmetries in two-dimensional conformal field theory generated by spin$S=1/2,1,\dots,3$ currents are investigated. For spins $S=5/2$ and $S=3$ the generators of the symmetry form associative algebras with quadratic determining relations. “Minimal models” of conformal field theory with such additional symmetries are considered.