A Systematic Improvement for Calculation to Conductivity in Anomalous   Propagation of Surface Acoustic Wave at $\nu={1/2}$
  We report a systematic improvement to calculate the conductivity which associates to the anomaly of the propagation of surface acoustic waves at $\nu={1/2}$ above a two-dimensional electron gas. We try to resolve the discrepancy between theoretical and experimental values for the magnitude of $\sigma_{xx}(q)$ by considering the contribution to the response functions from the self-interaction among the Chern-Simons gauge fluctuations. 
Yue Yu