"The hour" in the phrase, "the hour is coming," is idiomatic. It has the same sense in English as saying 'the time is coming.' It is not expressing any particular length of time. Thus, the foretold "last day" is "the time" for all those in the tombs to rise. And it starts at "the last trumpet" which coincides with the start of the day of judgment. (Rev 11:15, 18)
Resurrection, as an idea, is no more nonsensical than is teleportation on the Star Trek series. The idea is based on the theory of quantum entanglement. The NOVA series, The Elegant Universe discussed and illustrated the idea.
With enough memory and power a person (or anything for that matter) could be 'recreated' as it were. The idea of resurrecting a person is not out of the realm of known science. Humans are playing with the idea, but only one particle at a time last I read.