Question: Negative Group Delays and Action-at-a-Distance
  We comment on the paper by M. W. Mitchell and R. Y. Chiao, ``Causality and negative group delay in a simple bandpass amplifier", Am. J. Phys. 66 (1), 14-19 (1998). 
Andrew E. Chubykalo, Valeri V. Dvoeglazov (EFUAZ)