[Physicist]

A related thought problem: the Elitzur-Vaidman bomb-testing problem. If the only way to test a bomb is to trigger it and see whether it goes off, quantum mechanics can help you find which bombs would go off, without actually triggering them.

[IronJack]

If the (good) bombs exploded when hit with a single photon, wouldn't this experiment always detonate the good bombs? Isn't it basically the optical equivalent of throwing them against the wall?

I must be missing something.

[KayEyeDoubleDee]

I haven't thought about this too hard, but why doesn't a good bomb act like an observation, and collapse the wavefuntion prior to points C or D?