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Timeline for Definition of Entanglement

Current License: CC BY-SA 4.0

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Feb 1, 2019 at 9:08 answer added lcv timeline score: 0
Jan 31, 2019 at 18:46 history edited Qmechanic
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Jan 31, 2019 at 11:27 answer added anna v timeline score: 0
Jan 31, 2019 at 10:57 answer added Andrew Steane timeline score: 5
Jan 31, 2019 at 10:13 history edited Norbert Schuch CC BY-SA 4.0
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Jan 31, 2019 at 10:12 comment added Norbert Schuch @WillO One could also argue that people are used to think of mixed states when they see $\rho$ rather than $\psi$.
Jan 31, 2019 at 3:55 answer added PhysicsTeacher timeline score: 1
Jan 31, 2019 at 2:10 history edited user353840 CC BY-SA 4.0
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Jan 31, 2019 at 2:08 comment added user353840 @WillO fair enough, I will edit my question.
Jan 31, 2019 at 2:08 comment added user353840 @DanYand Well, the premise is that I have to explain to a bunch of experimentalists how this is a good definition for quantum entanglement and I have no idea how to do that.
Jan 31, 2019 at 1:59 comment added WillO Ah. Your post as written is quite misleading, then. It would help a lot if you clarified that you are talking about mixed states; to many readrers (including me) the unmodified word "state" refers to a pure state by default.
Jan 31, 2019 at 1:13 comment added user353840 @WillO That's true, but in that case you're only talking about pure states (= vector states). This definition deals with mixed states, i.e. density matrices. They are not elements of a Hilbert space, but rather operators acting on a Hilbert space. They are already normalised, so your point does not hold in this context.
Jan 31, 2019 at 1:09 comment added WillO A state is an equivalence class of vectors. Every linear combination is equivalent to a convex combination.
Jan 31, 2019 at 1:02 comment added user353840 @WillO That's not true. Every element is a LINEAR combination of $A \otimes B$, but I am talking about a CONVEX combination of tensors, i.e. $\sum_i \lambda_i = 1$.
Jan 31, 2019 at 0:56 comment added WillO It is nearly trivial to check that the tensor product consists entirely of states of the form you're calling separable. If you've found an article that suggests otherwise, you've found an article with a very elementary error.
Jan 31, 2019 at 0:55 review Close votes
Feb 1, 2019 at 11:09
Jan 31, 2019 at 0:46 comment added user353840 @WillO no, this is definitely the definition found in the literature, for example in this article definition 3
Jan 31, 2019 at 0:41 comment added WillO By this definition, no state is entangled. The correct definition is that a state is entangled if it is not a product state.
Jan 30, 2019 at 23:53 history asked user353840 CC BY-SA 4.0