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Starting with some background information from Wikipedia, we have that under time reversal the position is unchanged while the momentum changes sign. In quantum mechanics we can express the action of time reversal on these operators as $\Theta\,\mathbf{x}\,\Theta^\dagger = \mathbf{x}$ and $\Theta\,\mathbf{p}\,\Theta^\dagger = -\mathbf{p}$. It is worth ...

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Parity and Time reversal are by definition elements of the full lorentz group with which you need to supplement the proper orthochronous subgroup in order to be able to span the entire group. As noted, the proper way to define parity in any dimension is to flip one of the spatial axes. In even space-time dimensions it so happens that flipping all spatial ...

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No. A single measurement can't tell you if the state was in a superposition or it was a pure state. In order to be able to do that you must have knowledge of how the state was prepared, which means you must have gauged your apparatus and therefore performed a statistically relevant number of measurements on the very same state many times and taken note of ...

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