The Yangian symmetry of the Hubbard model

Abstract We have found a new hidden symmetry of the one-dimensional Hubbard model. We show that the one-dimensional Hubbard model on an infinite chain has an infinite-dimensional algebra of symmetries. This algebra is a direct sum of two sl(2)-Yangians. This Y(sl(2))⊕Y(sl(2)) symmetry is an extension of the well-known sl(2)⊕sl(2) one. The deformation parameters of the Yangians are proportional to the coupling constant of the Hubbard model Hamiltonian.