Timeline for Superposition of position eigenstates after measurement of position?
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 21, 2021 at 10:07 | vote | accept | Martin C. | ||
| Apr 13, 2018 at 10:16 | comment | added | Panos C. | So, eventually, it is really a matter of carefully counting how many possible states your systems had. If there are REALLY two states, then yes, the measurement would be an exact eigenstate given that your measuring device can distinguish between the two states. | |
| Apr 13, 2018 at 10:16 | comment | added | Panos C. | That's right. However there is a subtlety here. For example, in the Stern-Gerlach experiment, there are two possible states: spin up and spin down. But this regards the z-axes (the direction of the magnetic field). Of course no-one forbids you from measuring, say, the x-component of spin. Due to the non-commutative nature of angular momentum components, determining the spin at the direction of the x-axes, enforces the z-component to take values from a superposition of up and downs with respect to the z-axes. | |
| Apr 13, 2018 at 9:58 | comment | added | Martin C. | Ok. What about a two state system like a spin qubit? In that case I would expect an exact up/down answer. | |
| Apr 13, 2018 at 8:45 | history | answered | John Rennie | CC BY-SA 3.0 |