- #1
nomadreid
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- TL;DR Summary
- (a) If A and B are entangled for t<t0, and measured at t0, do they return to entanglement at t>t0? (b) trivially at t=t0?
(c) For A,B being two electrons in the same energy level in an atom, is the smallest E to measure spin the E to go to another energy level?
Three related questions:
(a) In a pair of entangled particles, after one is measured/observed/determined/collapsed, my understanding is that the measurement breaks the entanglement so that after the measurement, unless something happens to re-entangle them, they are no longer entangled. Correct?
(b) If you have entanglement at t<t0 and not at t>t0, what does one say for t=t0? Or is the question meaningful?
(c) If we have two electrons in the same energy level without being observed, their spin states are automatically entangled, right? (If wrong, ignore what follows.) So it should be impossible to determine the spin states while leaving them in the same energy level, because that would give the contradiction of them being both determined and indeterminate at the same time. Therefore one has to have the electron go to another level, at least temporarily (and if it drops back after the measurement, this would be a case of what I meant in (a) by "unless something happens to re-entangle them") in order to measure the spin, i.e., the minimum energy needed to measure would be the difference between two energy levels. Is this reasoning correct?
It is likely that even my fundamental understanding of entanglement is seriously flawed, and I will be happy to be corrected.
(a) In a pair of entangled particles, after one is measured/observed/determined/collapsed, my understanding is that the measurement breaks the entanglement so that after the measurement, unless something happens to re-entangle them, they are no longer entangled. Correct?
(b) If you have entanglement at t<t0 and not at t>t0, what does one say for t=t0? Or is the question meaningful?
(c) If we have two electrons in the same energy level without being observed, their spin states are automatically entangled, right? (If wrong, ignore what follows.) So it should be impossible to determine the spin states while leaving them in the same energy level, because that would give the contradiction of them being both determined and indeterminate at the same time. Therefore one has to have the electron go to another level, at least temporarily (and if it drops back after the measurement, this would be a case of what I meant in (a) by "unless something happens to re-entangle them") in order to measure the spin, i.e., the minimum energy needed to measure would be the difference between two energy levels. Is this reasoning correct?
It is likely that even my fundamental understanding of entanglement is seriously flawed, and I will be happy to be corrected.