The travel velocity of these two wave types is not the same (P-waves are faster than S-waves). Thus, if there is an earthquake somewhere, the first waves that arrive are P-waves. In essence, the gap in P-wave and S-wave arrival gives a first estimate of the distance to the earthquake.
With the mysterious U.S. Senator Eddie Morra (Bradley Cooper) providing him with a second drug to counteract NZT's deadly side effects, Brian uses his enhanced abilities to help FBI agent Rebecca Harris (Jennifer Carpenter).
In the same vein, ABC is debuting its own true crime mini-series tonight, Madoff, a two-parter starring Richard Dreyfuss as Bernie Madoff, the financier who ran a billion-dollar Ponzi scheme, and Blythe Danner as his wife Ruth.