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Re:PHYS771 Lecture 9: Quantum by Attrecomet on Thursday October 13, 2022 @06:29AM (#33189295)
No. The probability of an event is never, ever negative, even in quantum. We use the complex scalar product, c x c^*, to get probabilities, and those are necessarily positive even for complex numbers. The same is true for the generalization to functions required in quantum mechanics.

If your wave function at point (0,0,0) were i x delta(0) (i.e. a point-like particle perfectly located at the three-dimensional origin), the probability of finding the particle there isn't i^2, but i x i^* = i x (-i) = 1.

Re:PHYS771 Lecture 9: Quantum by femto on Thursday October 13, 2022 @06:32AM (#33189316)
Thanks!
Re:PHYS771 Lecture 9: Quantum by prof-dr-ir on Thursday October 13, 2022 @01:58PM (#33194355)
Surely that probability should be i x delta(0) x (-i) x delta(0) so, you know, your everyday squared Dirac delta function.
Re:PHYS771 Lecture 9: Quantum by Attrecomet on Thursday October 20, 2022 @06:46AM (#33272812)
I secretly did the integration over space to go from the probability density to the probability, so the deltas are integrated out :P

Doing calculations over text-based comments is so painful that I gloss over a lot, in the expectation that this isn't the right place to talk about anything but vague ideas anyway.