Quantum entanglement is the mechanism by which quantum correlations between two sub-systems survive even after being physically separated from an interaction region. The correlations could in principle survive without neither time nor space constraint.

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Quantum Entanglement - How To Interpret [duplicate]

I have thought about quantum entanglement for some time, and I still don't quite understand the reasoning behind the conclusion that entangled particles somehow can communicate their state to each ...
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Does entanglement have to be verified synchronously

I am not a physicist so, first of all I like to apologise if I my question is stupid. I just want to know where I am going wrong here. But if I have understood anything about the entanglement ...
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Producing energy with entanglement

If we entangle two electrons for example and move one of the electron to Mars for instance. Are we able to somehow transfer the kinetic force of Mars from its movement (spinning and orbitting) to ...
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Does the violation of Bell inequality by a classical field imply “classical entanglement”?

This article has been brought to my attention recently (free access) : Shifting the quantum-classical boundary: theory and experiment for statistically classical optical fields In the abstract, they ...
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Proof that entanglement is independent of distance

I've already read this quite often but never seen a proof—maybe it's just so clear to physicists, but I'm not really sure how to prove it. Currently I'm pretty confused so the following might be ...
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85 views

How does measurement affect multi-particle entangled particles?

It is my understanding that you can have two entangled particles, A and B, and measure their spins from two different angles, X and Y, such that: If you measure A using one angle (e.g. X), there's ...
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Is communication of the wavefunction via quantum entanglement possible?

Assume two particles are entangled and separated by an arbitrary distance. Particle 1 is in a potential well of width w1. If I'm not mistaken, the wavefunction of Particle 2 correlates to the ...
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Simultaneous measurement for quantum entanglement

In the simple example that we measure the spin of two entangled particles, we measure one to have spin up so we know the other has spin down. If we could (theoretically) measure both particles at the ...
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61 views

Which particles can or cannot be entangled?

Is Quantum entanglement limited to fundamental particles? If it is, then which particles can or cannot be entangled?
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Connection between bond-dimension of a matrix product state and entanglement

The bond dimension is the dimension of the truncated matrix product state (MPS). Let us assume that I am simulating some many-body system with high entanglement via the density matrix renormalization ...
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Why is it necessary for all the component-states to have same phase for interference?

I am currently reading Decoherence. In this site, it is written : Now here is the absolutely key point: every component eigenstate has an associated phase . It is this phase$^1$ which gives the ...
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35 views

Entanglement and Special Relativity [closed]

There are 2 particles entangled and move far apart to 2 measuring devices . The first measurement of either particle will collapse the wave function and set spin up and spin down on the particles. 2 ...
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38 views

Information and entaglement via determination of the first's system state with interaction

Could we have entangled systems (microscopical or macroscopical) and construct a way of altering the state of one of the two entangled parts (let's say by Alice) via interaction and thus making the ...
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Holographic dual of a massive QFT?

A naive question about holographic dual of a massive QFT: The Ryu-Takanayagi formula for the entanglement entropy (see their paper) seem to suggest that the holographic dual of a massive QFT (e.g. a ...
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Measuring quantum entanglement in paper by Ma et al [duplicate]

Looking at the links below, could somebody please explain how entanglement between Alice and Bob particles is established/deduced from Victor's choice/measurement? I understand that Alice and Bob can ...
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2answers
120 views

Quantum entanglement and the big bang

Prior to the Big Bang all matter was compressed into a point of high density. Why isn't all matter already entangled?
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Delayed choice entanglement swapping: why are Alice & Bob's measurements useless without Victor's?

Here is the article by Ma et al.:http://arxiv.org/abs/1203.4834 I have read many explanations on this site and others that emphasize that Victor's data is needed to make Alice and Bob's usable... ...
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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 ...
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73 views

Quantum Teleportation between Entangled Qubits

My question refers to the experiment described in this article: http://www.sciencemag.org/content/345/6196/532.abstract Here's a popular science description: ...
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108 views

Does quantum theory obey locality?

Bell's inequality together with the Aspect experiment shows that that we cannot have local realism. But does quantum theory obey locality? and if not how can locality be violated but not special ...
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58 views

Is there any quantum experiments or effects that you can do at home? [duplicate]

I have heard that you can do the double slit experiment, but is there any other experiments like particle entanglement or observer-induced state collapse?
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117 views

Why does a violation of locality not imply a violation of relativity?

This question is closely related to: What counts as information? Taking the specific example, again, of the EPR experiment. I think everyone agrees on the following: The act of measuring the ...
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The expectation value of entanglement entropy of composite system in a random pure state

I'm trying to compute the expectation value of entanglement entropy of composite system in a random pure state, but I'm running into some problems. The system we are considering is composed of two ...
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2answers
100 views

Is entanglement a consequence of the uncertainty principle?

I am an aspiring physicist and once, I asked my professor on what triggers quantum entanglement and he graciously remarked "The great uncertainty principle!" - I was slightly confused and didn't say ...
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Entanglement between the electrons in the Laughlin wave function

Consider the $1/3$-Laughlin wave function $$ \Psi \propto \exp \left(-\sum_i |z_i|^2 \right) \prod_{1\leq i<j\leq N} (z_i-z_j)^3 . $$ It cannot be written in the form of a Slater determinant, ...
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72 views

Geometric measure of entanglement in example with GHZ state

I'm learning about different possibilities to measure entanglement right now, and I'm struggling with the geometric measure. My question is probably quite trivial, but I can just not comprehend how ...
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Are Cosmic Microwave Background (CMB) photons entangled?

Suppose we'd like to know whether two cosmic microwave background photons emitted from different parts of the sky have any quantum correlation with each other. We could measure polarization of two ...
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What counts as information?

What counts as information? In e.g. the EPR experiment why is one entangled particle knowing instantaneously the state of the other not counted as 'information'. Edit Following a discussion in the ...
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Link between Hawking-Bekenstein Black hole entropy and entanglement entropy

I'm currently doing a project on two sided Ads-Schwarzschild black holes in the context of Ads/CFT. I want to show that the entanglement entropy between the two CFTs corresponds approximately to the ...
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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 ...
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How does this youtube video demonstrate quantum entanglement? [closed]

The following is an experiment that shows "spooky action at a distance" of quantum entanglement; that is, when we measure some properties of two entangled photons, we find that measuring property of ...
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48 views

Quantum probability of entangled spin-1/2 particles?

Let us say that you have two entangled spin-1/2 particles (entangled in such a away that angular momentum is conserved). Let us say particle 1 moves to the left and particle 2 to the right. We measure ...
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Operational difference between separable, entangled, PPT and NPT states

Given two parties Alice and Bob, a state $\rho_{AB}$ is said to be separable if it can be written as $\rho_{AB}=\sum_i p_i\rho^i_A\otimes\rho^i_B$, with $p_i$ being probabilities and ...
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Quantum Entanglement Particle Properties

I have background in static/dynamic/thermodynamic physic. I am reading on quantum physics and quantum entanglement. Me and some of my colleagues were wondering on the properties that are shared ...
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272 views

How come the concept of an instant of time is such a controversial topic with relativity, but with entanglement it's completely acceptable?

When talking about relativity most people say that a universal instant of time doesn't exist, but when talking about entanglement most will say that the particles are both measured instantaneously. ...
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How can a correlation be teleported?

I am aware of how a qubit can be teleported from party $A$ to party $B$ if both the parties are entangled. Is there a similar way to teleport a correlation? I googled and found Entanglement ...
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Measuring electron spin with multiple Stern–Gerlach apparatus at an angle

To separate the two spins of electron of a particular direction, we use Stern-Gerlach apparatuses to apply a non-uniform Magnetic field. Suppose we have two identical electrons and we know their spin ...
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39 views

Entanglement of Tripartite States

Is there any simple algorithm to determine the entanglement of a tri-partite state? In particular, what is the proof for entanglement of $ |GHZ\rangle $ and $ |W\rangle $ states? $ |GHZ\rangle ...
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139 views

Is entanglement a classical phenomenon (last attempt)?

This is a reformulation of two previous questions that seem to have been misunderstood, or most likely, I failed to make them clear. I thank all people that answered, even the belligerent ones. Some ...
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Is entanglement a classical phenomena (2)? [closed]

The answer to this question seems to be yes, because you can simulate it with a classical computer and thus by a local classical theory (rule 110 CA) (see this question). However most people ...
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Can quantum entanglement be simulated on a digital computer to any degree of precision?

First principles modelling of physical phenomena has been very successful in physics. The largest limitation is perhaps the fact that many QM problems are NP hard so we would need really powerful ...
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Creation of a non-maximally entangled photon state

I'm reading a paper on testing the Bell Eberhard Inequality. The experiment performs polarization tests on states of the following form: $|\Psi_r>=\frac{1}{\sqrt{1+r^2}}(|HV>+r|VH>)$, where ...
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81 views

Doesn't the concept of “hidden variables”, by definition, encompass all possible results? [closed]

While i don't know all the mathematical/experimental specifics i know enough about entanglement/bell's theorem to know the general ideas of what's going on. It's definitely interesting but i'm not ...
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Question regarding entanglement

Could the paradoxical nature of entanglement be the result of a change in the nature of quantum properties, or an incomplete understanding of such, instead of non-locality?
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Entanglement and the uncertainty principle

Suppose you have two maximally entangled particles. You measure the spin about the x axis of the first and the spin about the y axis of the second. But both spins cannot be known simultaneously, so ...
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45 views

The “spooky action at a distance” and reference frame

It is often said that the measurement in EPR experiment is instant, as somehow described as "spooky action at a distance". However, the notation of equal time depends on reference frame, according to ...
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Entanglement of two particles with same values of the entangled parameters?

The question For an entangled state consisting of systems A and B, if A is measured when does the wavefunction at B collapse? contains next entangled state: If there are two systems A and B, with ...
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For an entangled state consisting of systems A and B, if A is measured when does the wavefunction at B collapse? [duplicate]

If there are two systems A and B, with an entangled state consisting of $$\mid \psi \rangle = \frac{1}{\sqrt{2}} (\mid \uparrow _A \rangle \,\, \otimes \mid \uparrow _{B} \rangle \,+ \mid \downarrow ...
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Is This A Working Time Machine? [duplicate]

picture taken from this video for those who do not like to click on youtube links youtube video - retrocausality through Double Slit & Bose The answer will probably be no, but i am interested ...
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Entanglement of coherent states

I am new to quantum optics and I am trying to understand whether coherent states of the field could be entangled. Let's consider, for example, a two-mode state: $|\psi^{AB} \rangle = \frac{1}{c} ...