Instruct: Classify the given Amazon review as either positive or negative.
Query: Quantum mechanics with a plot: entertaining.

This is truly a hard-sf whodunit. The Hero is an ex-cop private eye with so much physics under his belt to make me wonder . . .. The mystery peels off like an onion, revealing another mystery, on and on. Meanwhile, the reader is educated on non-obvious speculations on the nature of reality from the standpoint of a hard-core scientist--the Hero is one intellectual PI indeed. Plot flows well, but leaves a couple of loose end, and sadly, the closing is weak. Dialogue is usually good, but sometimes the narration is too didascalic, I feel I'm not reading fiction, yet it's so interesting that I don't care. Characters are almost credible . . .. But then, I'm picky. Don't look for sense of wonder, though