- #1
junhui.liao
- 7
- 0
Hi, guys,
As a beginner, I have some problems to understand QM.
Thanks a lot in advance for your response !
1. According to QM interpretation, the measured particles, they become spike, do they have chances to back normal status (the status before becoming spikes)? If yes, how? if no, why?
2. If I understand correctly, any kinds of particles, after being measured, become same spikes(described by Dirac function), or not? it sounds very artificial / weird if it is. Naively, how (god?) could make the particles become same spikes just after being measured? Or the same spikes postulation is just a temporary successful theory/model which has sustained experimental test for a few decades?
3. According to QM, the expectation value <x> is the average of repeated measurements on an ensemble of identically prepared systems. Then when calculating momentum p = mv, what's the "m" ? It's the average mass of those "an ensemble of identically prepared systems" ? If yes, then how to know the number of systems were involved when measurement was processed? If not, it would be the sum of mass of all measured systems? So, if this interpretation is correct, then the momentum is a kind of "hybrid" quantity in the sense of the <v> = d<x>/dt come from average value while the "m" come from sum of all systems. Or, I missed everything?
BTW, I'm mainly reading Griffiths QM, 2nd version, international edition.
Thanks again !
Cheers,
JH
As a beginner, I have some problems to understand QM.
Thanks a lot in advance for your response !
1. According to QM interpretation, the measured particles, they become spike, do they have chances to back normal status (the status before becoming spikes)? If yes, how? if no, why?
2. If I understand correctly, any kinds of particles, after being measured, become same spikes(described by Dirac function), or not? it sounds very artificial / weird if it is. Naively, how (god?) could make the particles become same spikes just after being measured? Or the same spikes postulation is just a temporary successful theory/model which has sustained experimental test for a few decades?
3. According to QM, the expectation value <x> is the average of repeated measurements on an ensemble of identically prepared systems. Then when calculating momentum p = mv, what's the "m" ? It's the average mass of those "an ensemble of identically prepared systems" ? If yes, then how to know the number of systems were involved when measurement was processed? If not, it would be the sum of mass of all measured systems? So, if this interpretation is correct, then the momentum is a kind of "hybrid" quantity in the sense of the <v> = d<x>/dt come from average value while the "m" come from sum of all systems. Or, I missed everything?
BTW, I'm mainly reading Griffiths QM, 2nd version, international edition.
Thanks again !
Cheers,
JH