All Questions
Tagged with quantum-entanglement hilbert-space
163
questions
4
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2
answers
938
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When can a Hilbert space with a given Hamiltonian be decomposed into non-interacting tensor product factors?
Let's say I have a Hilbert space $\mathcal{H}$ (either finite-dimensional or with a countably infinite basis) with a specified Hamiltonian $\hat{H}$, representing some quantum system. Under what ...
1
vote
2
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949
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Separability in quantum physics
I am under the impression that violations of Bell's inequality as shown in e.g. the Aspect experiment can be explained by the fact that the particles where not separable rather then the non-existence ...
9
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1
answer
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Methods to distinguish between pure/mixed states and entangled/separable states
I'm a little confused about how we can distinguish between pure/mixed states and entangled/separable states and I would really appreciate some help!
I understand a density operator $\rho$ represents ...
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10
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2
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Does correlation of the measurement outcomes imply that a state is entangled?
As per Wikipedia:
Quantum entanglement is a physical phenomenon that occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot ...
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6
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2
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674
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Why is the dimension of the set separable states $\dim\mathcal H_1+\dim\mathcal H_2$?
Please can you help me to understand how the dimension of the set of separable states is $\dim \cal H_1 + \dim \cal H_2$?
This is the relevant passage:
So far, we have assumed implicitly that the ...
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5
votes
2
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2 entangled electrons in QFT
In field theory, by quantizing a dirac field, we can obtain a creation operator for a single electron of definite momentum, of definite spin up or down, these respectively are:
$$a^\dagger_{+}(p)|0\...
- 2,857
3
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1
answer
686
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What is meant by a quantum factoring for entangled states?
The definition of an entangled state $|\Psi\rangle$ is that it CANNOT be factored into
$$|\Psi\rangle=|\psi\rangle_1\otimes|\phi\rangle_2$$
I am kind of confused on what is meant by a quantum ...
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16
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3
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Entangled or unentangled?
I got a little puzzled when thinking about two entangled fermions.
Say that we have a Hilbert space in which we have two fermionic orbitals $a$ and $b$. Then the Hilbert space $H$'s dimension is just ...
- 4,420
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0
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453
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Can experiment distinguish the basis in which a singlet state is represented?
Let $\left(|\uparrow\rangle,|\downarrow\rangle\right)$ and $\left(|\nearrow\rangle,|\swarrow\rangle\right)$ be two bases of the $2$-dimensional Hilbert space $H$.
Can an experiment distinguish ...
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22
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What is a completely positive map *physically*?
This can be considered as a continuation of this question.
What does it mean to be a completely positive map, from a Physics point of view?
A positive map $h:\mathcal{B(H)}\rightarrow\mathcal{B(K)}$ ...
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7
votes
2
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332
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Under what assumptions can we split a Hilbert space into subspaces?
I was thinking about an apparently simple question about quantum mechanics, if I am looking at a quantum system described by a Hilbert space $\cal{H}$ under what hypothesis can I define A and B as ...
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18
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What Shannon channel capacity bound is associated to two coupled spins?
The question asked is:
What is the Shannon channel capacity $C$ that is naturally associated to the two-spin quantum Hamiltonian $H = \boldsymbol{L\cdot S}$?
This question arises with a view ...
John Sidles
9
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3
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What is quantum entanglement? [closed]
What is quantum entanglement?
Please be pedagogical.
Edit: I have updated my background under my profile.
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