New answers tagged observables
6
votes
Are quantum measurements on two different particles always commutative?
Yes, they commute. However, it's not correct to talk about the commutator $[A,B]$ because these are operators defined on different Hilbert spaces.
When you have a system of two particles, the state of ...
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3
votes
Are quantum measurements on two different particles always commutative?
I haven't seen it explicitly stated either, but it follows directly from definitions.
If $A$ is an observable associated with only the first particle, then by definition, it actually takes the form $...
- 104k
3
votes
What' the intuition behind Shankar's postulate II?
I don't know if it's the intuition, but here's one way in which one could arrive at the postulate.
When you are first introduced to quantum mechanics, you usually don't work in an abstract Hilbert ...
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4
votes
Accepted
What' the intuition behind Shankar's postulate II?
In classical physics the evolution of the position and momentum of a particle are described by functions $x(t),p(t)$ whose values are the value you would get if you measured the position and momentum ...
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1
vote
What' the intuition behind Shankar's postulate II?
You don't rationalize postulates. Postulates are the "starting point", and the rest of the theory builds from them. Then we test the validity of the set of postulates and the theory by ...
- 58.2k
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