Hello ratioinator,
Please tell us why this is not evidence, in the double slit experiment, in the PBS Video 'Quantum Eraser', where electrons go back in time to change their course of travel, when scientists look, observe, measure, (what ever term you want to use) them.
Well, the most obvious answer is that they *don't* go back in time. That is a false reading of the results brought upon by trying to give a classical treatment of a quantum experiment.
The big problem is the expectation that electrons will only be in one location at each time. And that is a false assumption. The electrons in this experiment are in a superposition stage that goes over *both* paths and recombines at the end to either give an interference pattern or not.
A proper, quantum mechanical, treatment only has electrons going forward in time according to the probabilistic principles of quantum mechanics. It is only when you try to explain the situation using classical (and incorrect) views that you get such nonsense as causes going backward in time.