  It is shown that the local quantum field theory of the chiral energy-
momentum tensor with central charge $c=1$ 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 to $W$-algebra extensions of the Virasoro algebra.

High Energy Physics - Theory