LogFAQs > #926355162

iirc, quantum mechanics is deterministic* in the sense that a given particle's wavefunction is a well-defined function that can--in principle--be precisely known/predicted at all points in time. However knowledge of a particle's wave function doesn't necessarily tell you what the particle's position/speed at any given time is--it only gives a probability distribution describing what positions/velocities might be obtained if the quantity were measured. (And in the classical limit, these probability distributions become extremely sharply peaked delta functions which results in the Newtonian physics we are intuitively more familiar with)

Whether or not this distinction matters to you I don't know.

*Whether or not this actually means quantum mechanics is "deterministic" in any meaningful sense is also an open question, but I don't really care about the semantics argument associated with that.
---

Oh woops. Putting Advokaiser in my sig like this until I think of something more clever