A new view of the virasoro algebra

It is shown that the local quantum field theory of the chiral energy-momentum tensor with central chargec = 1 coincides with the gauge invariant subtheory of the chiral SU(2) current algebra at level 1, where the gauge group is the global SU(2) symmetry. At higher level, the same scheme gives rise toW-algebra extensions of the Virasoro algebra.