Towards solving QCD in light-cone quantization: The spectrum of the transverse zero modes for SU(2)

The formalism for a non-Abelian pure gauge theory in 2+1 dimensions has recently been derived within discretized light-cone quantization, restricting to the lowest transverse momentum gluons. It is argued why this model can be a paradigm for full QCD. The physical vacuum becomes nontrivial even in light-cone quantization. The approach is brought here to tractable form by suppressing by hand both the dynamical gauge and the constraint zero mode, and by performing a Tamm-Dancoff-type Fock-space truncation. Within that model the Hamiltonian is diagonalized numerically, yielding mass spectra and wave functions of the glueball states. We find that only color singlets have a stable and discrete bound state spectrum. The connection with confinement is discussed. The structure function of the gluons has a shape such as [x(1-x)]1/3. The existence of the continuum limit is verified by deriving a coupled set of integral equations. copyright 1996 The American Physical Society