What about that nuclear bomb on last night's "Lost"?

"Lost" viewers at Popular Mechanics were reeling after watching the latest episode of "Lost," in which Faraday discovers (among other surprises) that there's a hydrogen bomb on the island.  Popular Mechanics asked nuclear weapons expert Ivan Oelrich, vice president for the strategic security program at the Ploughshares-funded Federation of American Scientists (FAS), to give them a primer on the workings of hydrogen bombs and to weigh in on whether last night's plot was "as realistic as Widmore sinking a plane in waters too deep for recovery or if it’s as unlikely as Hurley throwing out a jug of Dharma ranch dressing."  Just as they predicted, the plot combined both good science and bad.