Timeline for Explanation for the EPR-like paradox
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 17, 2015 at 22:51 | comment | added | pwf | I don't understand that last question. But the issue is not trying to synchronize the $p$ and $x$ measurements; it's trying to identify the time that the $p$ measurement belongs to. It's necessarily spread out in time, so that means the corresponding $x$ measurement is imprecise in time no matter how well synchronized to the $p$ measurement, and that means that $x$ itself is imprecise. | |
| Feb 17, 2015 at 21:39 | vote | accept | xyz | ||
| Feb 17, 2015 at 21:39 | |||||
| Feb 17, 2015 at 21:35 | vote | accept | xyz | ||
| Feb 17, 2015 at 21:39 | |||||
| Feb 17, 2015 at 21:32 | comment | added | xyz |
So you're saying that it's impossible to simultaneously measure (experiment) both p and x (at the exact same time t because I can never synchronize)? If I repeated this experiment with all possible` t1 (start to dp measure) < dt (time after x is measure after t1) < t2 (end of dp measure)`, I would get a result close to h/4pi but never equal?
|
|
| Feb 17, 2015 at 21:15 | comment | added | pwf | To choose $\Delta p$ arbitrarily small for the electron you must take some time to make the measurement. When are you then going to measure $x$ for the positron? If you measure it at the beginning of the $p$ measurement, I can say, "But that's not exactly the position I wanted - the positron must have been a little farther on when the electron had momentum $p$." If you measure $x$ at the end of the $p$ measurement, I'll say, "No, it must have been a little closer than that." So you won't be able to make $\Delta x$ arbitrarily small; it is limited by how small you want to make $\Delta p$. | |
| Feb 17, 2015 at 21:05 | comment | added | xyz |
From QM dx*dp >= h/(4*pi). So I can choose dx arbitrarily small for the positron, dp arbitrarily small for the electron, so as to violate above. For one particle, this I can understand your explanation, but I don't get this analogy for two particles.
|
|
| Feb 17, 2015 at 20:52 | history | answered | pwf | CC BY-SA 3.0 |