Quantum mechanics - question about the system

Click For Summary
SUMMARY

The discussion centers on the implications of measuring a quantum system in state |\psi\rangle and whether such measurement alters the system's state, specifically questioning if the system can remain in state |\phi\rangle post-measurement. The participants explore the use of projection operators, such as |\phi\rangle \langle \phi |, to describe state evolution and the challenges of normalization. The conversation references the Neumann interpretation of quantum mechanics as a potential framework for understanding measurement without destroying the initial state.

PREREQUISITES
  • Understanding of quantum states and notation, specifically Dirac notation.
  • Familiarity with projection operators in quantum mechanics.
  • Knowledge of Hilbert space concepts and quantum state evolution.
  • Awareness of the Neumann interpretation of quantum mechanics.
NEXT STEPS
  • Research the mathematical formulation of quantum measurement theory.
  • Study the implications of the Neumann interpretation in quantum mechanics.
  • Learn about normalization techniques for quantum states.
  • Explore the role of projection operators in quantum state evolution.
USEFUL FOR

Quantum physicists, students of quantum mechanics, and researchers interested in the measurement problem and state evolution in quantum systems.

paweld
Messages
253
Reaction score
0
Let's asssume our system is in state [tex]|\psi\rangle[/tex]. If we want to ask a true/false question about the system e.g. "Is the system in state [tex]|\phi \rangle[/tex]?" does it always implay that after experiment which aims at answering this question the system will be in state [tex]|\phi \rangle[/tex]. Could we answer this question and don't destroy the initial state (or destroy in another way).
Does it mean that during such experiment the state evolution is desciribe by the following projection operator: [tex]|\phi \rangle \langle \phi |\psi\rangle[/tex]. Unfortunately this stae is unormallised. How we can describe the evolution of system during experiment by operator in Hilbert space.
 
Physics news on Phys.org

Similar threads

  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 2 ·
Replies
2
Views
386
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 18 ·
Replies
18
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 21 ·
Replies
21
Views
4K