Quantum entanglement is the phenomenon of two particles depending on each other, once they have interacted, even after becoming physically separated.
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Why quantum entanglement is considered to be active link between particles?
From everything I've read about quantum mechanics and quantum entanglement phenomena it's unobvious for me, why quantum entanglement is considered to be active link. I.e. it's stated every time that ...
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3answers
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Quantum entanglement faster than speed of light?
recently i was watching a video on quantum computing where the narrators describes that quantum entanglement information travels faster than light!
Is it really possible for anything to move faster ...
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11answers
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Could the Heisenberg Uncertainty Principle turn out to be false?
While investigating the EPR Paradox, it seems like only two options are given, when there could be a third that is not mentioned - Heisenberg's Uncertainty Principle being given up.
The setup is this ...
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Entangled particles
So we have two particles (A and B) that are entangled.
From what I understand, entanglement isn't destroyed, it is only obscured by subsequent interactions with the environment.
Particle A goes ...
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7answers
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Quantum Entanglement - What's the big deal?
Bearing in mind I am a layman - with no background in physics - please could someone explain what the "big deal" is with quantum entanglement?
I used to think I understood it - that 2 particles, say ...
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Energy Measurements in a Two Fermion Double Well System
This question is related but my question here is much more elementary than discussions of the Pauli principle across the universe.
There has been a fair amount of discussion around at the moment on ...
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1answer
324 views
A physical understanding of fractionalization
all! Is there a physical understanding of fractionalization in condensed matter physics? The textbook approach is theoretical, not physical. I'm thinking of spin-charge separation for electrons, the ...
10
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1answer
452 views
Entanglement in time
Quantum entanglement links particles through time, according to this study that received some publicity last year:
New Type Of Entanglement Allows 'Teleportation in Time,' Say Physicists at The ...
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0answers
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Information scrambling and Hawking non-thermal radiation states
Could a very small black hole where half of its entropy has been radiated, emit Hawking radiation that is macroscopically distinct from being thermal? i.e: not a black body radiator. Or would the ...
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What is quantum entanglement?
What is quantum entanglement?
Please be pedagogical.
Edit: I have updated my background under my profile.
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1answer
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EPR-type experiments and faster-than-light communication using interference effects as signaling mechanism
I understand that faster-than-light communication is impossible when making single measurements, because the outcome of each measurement is random. However, shouldn't measurement on one side collapse ...
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2answers
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Vasiliev gravity and “holographic” entanglement
It has been proposed that AdS/CFT arises because of the entanglement structure of quantum field theories, e.g. see the discussion which occurred right here. Until now I have been skeptical of the ...
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5answers
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Is there such a thing as “Action at a distance”?
What ever happened to "action at a distance" in entangled quantum states, i.e. the Einstein-Rosen-Podolsky (EPR) paradox? I thought they argued that in principle one could communicate faster than ...
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Quantum Computing and Animal Navigation
Someone sent me this link to a talk by Prof. Klaus Schulten from the University of Illinois: (my emphasis)
Quantum Computing and Animal Navigation
Quantum computing is all the rage nowadays. ...
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8answers
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Given entanglement, why is it permissible to consider the quantum state of subsystems?
Quantum entanglement is the norm, is it not? All that exists in reality is the wave function of the whole universe, true? So how come we can blithely talk about the quantum state of subsystems if ...
6
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1answer
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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 ...
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0answers
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Local explanation of the Aharonov-Bohm effect in terms of force fields
Here is an interesting paper for the Physics SE community: On the role of potentials in the Aharonov-Bohm effect, Lev Vaidman, published in PHYSICAL REVIEW A 86, 040101(R) (2012).
You should check it ...
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6answers
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Is quantum entanglement an objective or subjective property?
Imagine the following gedankenexperiment. Observer Alice is right here on Earth. Observer Bob is at say Alpha Centauri. A pair of maximally entangled qubits is formed with one qubit handed over to ...
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2answers
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A resource theory of quantum discord?
Local Operations and Classical Communication (LOCC) is the classic paradigm for studying entanglement. These are things that are `cheap' and unable to produce entanglement as a resource for a quantum ...
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1answer
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Why do we want to entangle qubits?
The title is pretty much all I want to ask. Why are qubits entangled? To my knowledge (which isn't that deep) a quantum register can be realized without entangling the qubits.
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1answer
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Can two particles remain entangled even if one is past the event horizon of a black hole?
Can two particles remain entangled even if one is past the event horizon of a black hole? If both particles are in the black hole?
What changes occur when the particle(s) crosses(cross) the event ...
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1answer
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Detecting coherence
Is there a way to know if a particle is acting as a wave or a particle? Alternatively, if an entangled particle was already measured?
A - Yes
So any experiment over an entangled particle that let ...
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2answers
398 views
Has anyone actually “seen” entanglement?
I want to know if the following has been done experimentally; after the spin (or any other characteristic with a probability of 50%) of 2 entangled particles has been measured, we change the spin of ...
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2answers
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What is time teleportation?
I read this article about time teleportation.
Can someone explain the concept better?
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Equivalence of simple formulations of qubit entanglement
I'm reading some very elementary treatments of quantum computation and am unsure about the correspondence among "definitions" of qubit entanglement.
One definition states that (1) the bits of a ...
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0answers
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State of the entangled particles at the event horizon of black hole
Looking through the article of Samir Mathur http://arxiv.org/abs/0909.1038
he assumes that the entangled particles created at the event horizon have all the state ...
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10answers
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Is quantum entanglement mediated by an interaction?
You can get two photons entangled, and send them off in different directions; this is what happens in EPR experiments. Is the entanglement then somehow affected if one puts a thick slab of EM ...
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3answers
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Does this Zeilinger group result provide experimental proof of backward-in-time causation?
Does this recent Zeilinger group delayed choice entanglement experiment imply backward-in-time influences?
http://arxiv.org/abs/1203.4834
From the abstract: "This can also be viewed as “quantum ...
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2answers
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Is quantum entanglement functionally equivalent to a measurement?
I saw the following talk the other day: http://www.youtube.com/watch?v=dEaecUuEqfc&feature=share
In it, Dr. Ron Garret posits that entanglement isn't really that "special" of a property. He ...
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0answers
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Does the passage of time effect a photons entanglement with another?
I recently read an article about "Delayed-choice entanglement swapping". Here is an excerpt from the article:
Delayed-choice entanglement swapping consists of the following steps.
(I use the ...
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3answers
436 views
Local measurement of entangled particle pairs and interpretation of state
This just started to bother me after reading yet another entangled particle question, so I hate to ask one myself, but...
If we have two entangled particles and take a measurement of one, we know, ...
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1answer
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Exploiting the Heisenberg Uncertainty Principle as a means to communicate
It seems as though I've come across a rather unusual conclusion that could either simply be a misinterpretation or a contradictory discovery. I seem to have found a way to utilize the Heisenberg ...
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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 ...
