All Questions
8
questions
4
votes
1
answer
1k
views
Relationships between elements in the density matrix
Say we have a density matrix for a spin-1 system given by:
$$
\hat \rho = \left[\begin{array} A \hat \rho_{00}& \hat \rho_{01} & \hat \rho_{02} \\
\hat \rho_{10} & \hat \rho_{11} & \...
- 93
4
votes
1
answer
491
views
can entangled photons produce an interference pattern?
Suppose you have a laser that emits entangled photons in opposite directions towards a double-slit screen setup as shown below.
The photons are entangled such that if a photon on the left travels ...
- 131
-3
votes
1
answer
106
views
Never ending quantum superposition? [closed]
So I am wondering over the Copenhagen Interpretation how can a decoherence or measurement ever happen. If in the beginning of the universe everything was in a state of coherence being in ...
8
votes
2
answers
516
views
Conservation of quantum coherence?
Is coherence conserved under unitary transformation?
As we saw in the process of generating entanglement, coherence between states of the subsystem is transferred to quantum correlations (related to ...
- 151
21
votes
5
answers
5k
views
Entanglement and coherence
I have come across a wonderful review of entanglement by Chris Drost in his answer to this post. One part that left me puzzled was: (This post is merely an attempt to understand a portion of Chris' ...
- 1,611
2
votes
0
answers
263
views
What is the relationship between coherent states and quantum coherence?
What is the relationship between coherent states and quantum coherence? To me coherent states were only talked about in regard to Quantum Harmonic Oscillator, whereas coherence and decoherence on the ...
- 51
11
votes
4
answers
20k
views
What is coherence in quantum mechanics?
What are coherence and quantum entanglement? Does it mean that two particles are the same?
I read this in a book called Physics of the Impossible by Michio Kaku. He says that two particles behave in ...
user29660
7
votes
1
answer
3k
views
Coherence, Entanglement, Correlation
Let's deal specifically with a two-level system. I understand that ``coherence'' is due to the off-diagonal elements in the density matrix $\rho(t) = \sum_{i}|\psi_i(t)\rangle p_i\langle\psi_i(t)|$ ...
- 552