Are there physical phenomena, such as wave function collapse or black holes, which irrevocably destroy information about their prior states?
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$\begingroup$ It sounds like you already know about the potential scenarios where information could possibly be destroyed since you listed them as examples in your question. $\endgroup$ – zephyr Jun 9 '17 at 12:37
This is one of the current questions of cosmology/physics. So far all evidence points to the negative inside a black hole so far as quantum numbers go, but it's not clear what you're considering as "prior state."
A simple counter-example is a camera. Once the photons are absorbed by the film or solid-state sensor, all phase information is lost. Is that what you were looking for?