Zero Modes in a $c = 2$ Matrix Model
Recently \REF\dk{Simon Dalley and Igor Klebanov,'Light Cone Quantization of the $c=2$ Matrix Model', PUPT-1333, hepth@xxx/920705} \refend Dalley and Klebanov proposed a light-cone quantized study of the $c=2$ matrix model, but which ignores $k^{+}=0$ contributions. Since the non-critical string limit of the matrix model involves taking the parameters $\lambda$ and $\mu$ of the matrix model to a critical point, zero modes of the field might be important in this study. The constrained light-cone quantization (CLCQ) approach of Heinzl, Krusche and Werner is applied . It is found that there is coupling between the zero mode sector and the rest of the theory, hence CLCQ should be implemented.