Nitpick much? I meant more along the lines of when the assumptions aren't met, e.g. P(B) == 0. Or, where unitarity in physics isn't met: http://en.wikipedia.

Nitpick much? I meant more along the lines of when the assumptions aren't met, e.g. P(B) == 0. Or, where unitarity in physics isn't met: http://en.wikipedia.org/wiki/Unitarity_(physics) http://en.wikipedia.org/wiki/Unitarity_(physics)