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Quantum Entanglement ?


interested

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43 minutes ago, interested said:

 According to research by Prof. Juan Yin and colleagues at the University of Science and Technology of China in Shanghai, the lower limit to the speed associated with entanglement dynamics – or "spooky action at a distance" – is at least 10,000 times faster than light."

The spooky action is instantaneous (or nearly so). No information is communicated to you faster than c. You know the state of both particles when you make the measurement, because that information is contained in what you measure.

 

The "spooky action" and information transfer are separate concepts in entanglement. It is a mistake to conflate them.

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3 hours ago, swansont said:

The spooky action is instantaneous (or nearly so). No information is communicated to you faster than c. You know the state of both particles when you make the measurement, because that information is contained in what you measure.

 

The "spooky action" and information transfer are separate concepts in entanglement. It is a mistake to conflate them.

Is it agreed my previous summary was correct except perhaps a little speculative ref worm holes and information transferring through them.

I think I agree The "spooky action" and information transfer should be kept as two separate subjects so as not to confuse the subject any further.

The link posted earlier https://en.wikipedia.org/wiki/Quantum_entanglement covers most of my questions BUT NOT ALL!

Focusing on quantum entanglement of particles what is the maximum range this can be achieved over. Do the particles need to be in close proximity for it this to occur, or can they be separated by large distances.? Does entanglement work better at near or absolute zero? How stable or large does a particle have to be, ie can virtual particles be entangled or does the particle need to be stable before it can be entangled, ? Do virtual particles last longer at absolute zero enabling them to be entangled for a short time.

 

4 hours ago, Strange said:

That is an extremely speculative concept that is just based on an apparent mathematical similarity. It is not yet established to be the case. The standard, and very simple, explanation is just that quantum effects are non-local (in both time and space).

The speculation came from one of the earlier links posted, but does make sense of the mathematics and what is happening.

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7 minutes ago, interested said:

 Focusing on quantum entanglement of particles what is the maximum range this can be achieved over. Do the particles need to be in close proximity for it this to occur, or can they be separated by large distances.? Does entanglement work better at near or absolute zero? How stable or large does a particle have to be, ie can virtual particles be entangled or does the particle need to be stable before it can be entangled, ? Do virtual particles last longer at absolute zero enabling them to be entangled for a short time.

Particles have to be indistinguishable with regard to the state that is entangled.  i.e. if you entangle the polarization of photons, you can't have that polarization be associated with the direction of emission. That doesn't require co-location, but it makes the process easier.

AFAIK, virtual particles have nothing to do with this. That is a separate topic.

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On ‎16‎-‎8‎-‎2017 at 4:11 PM, interested said:

Does entanglement work better at near or absolute zero?

There is a link between a temperature that is nearly 0 K and many body entanglement.

"A many-body quantum system is cooled to zero temperature so that it is forced into its overall non degenerate ground state. We discuss the measurement of a sub-system Hamiltonian and demonstrate that it can be found in an excited state with a probability that depends on the coupling to its environment. This non-intuitive result is a pure quantum phenomenon" https://arxiv.org/pdf/cond-mat/0311647.pdf

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The following link might also be of interest to you, it is a bit more general than itoeros but points to the fact that all things could be entangled to a certain extent. It still does not answer your question ref range of seperation things can be entangled at.

http://discovermagazine.com/2016/jul-aug/entanglement

On 17/08/2017 at 6:48 PM, Itoero said:

There is a link between a temperature that is nearly 0 K and many body entanglement.

"A many-body quantum system is cooled to zero temperature so that it is forced into its overall non degenerate ground state. We discuss the measurement of a sub-system Hamiltonian and demonstrate that it can be found in an excited state with a probability that depends on the coupling to its environment. This non-intuitive result is a pure quantum phenomenon" https://arxiv.org/pdf/cond-mat/0311647.pdf

Itoero that link is incredibly interesting, the same arguments must exist in space also. 

Can matter form by the process of many body entanglement in space. Question mark

Edited by Handy andy
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On ‎16‎/‎08‎/‎2017 at 3:18 PM, swansont said:

Particles have to be indistinguishable with regard to the state that is entangled.  i.e. if you entangle the polarization of photons, you can't have that polarization be associated with the direction of emission. That doesn't require co-location, but it makes the process easier.

AFAIK, virtual particles have nothing to do with this. That is a separate topic.

Can you explain a little more ref teleportation? If the information is sent at light speed from points A to B, is the information destroyed at point A on teleportation?

Also what would happen if two atomic clocks were entangled and one was flown around the world, whilst the other was at a fixed location?

Thanks Handy aandy and Itoero for the links
 BUT

3 hours ago, Itoero said:

-Particles are entangled because a quantum state is entangled (like the spin of an electron). This can only happen because of some form of interaction. They will probably find several new ways of how particles or objects can interact to form entanglement...this will give more info concerning the range of separation in which particles or objects can get entangled at.

-This concerns a model called Holographic Entangled Space time. According to this model...when you disentangle two regions in space then there appears energy which distorts the space...Energy is mass.(E=mc²) If this model is correct then there is a possibility that mass or energy can form because of the breaking of many body entanglement.

 

Does this effect how matter is created in the early universe, or the Big bang theory?

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On 8/18/2017 at 2:44 PM, interested said:

Can you explain a little more ref teleportation? If the information is sent at light speed from points A to B, is the information destroyed at point A on teleportation?

 

 

Yes. You can't "clone" quantum states.

Quote

Also what would happen if two atomic clocks were entangled and one was flown around the world, whilst the other was at a fixed location?

The moving one would run at a different rate.

This is moot for most clocks, since they are measured at intervals much shorter than a trip around the world would take. The measurement would destroy the entanglement.

If you entangled e.g. a pair of atoms or ions in the clock transition state and transported one, it makes for an interesting question. It's possible the entanglement would be broken. Or it could just be that you just add an overall phase to the correlation. IOW, if you had a superposition of ground and excited state, if your proper time shifted the right amount, the correlation would change so that they were both excited or both ground when measured. Wait longer, and it's back to one of each.

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1 hour ago, swansont said:

Yes. You can't "clone" quantum states.

The moving one would run at a different rate.

This is moot for most clocks, since they are measured at intervals much shorter than a trip around the world would take. The measurement would destroy the entanglement.

If you entangled e.g. a pair of atoms or ions in the clock transition state and transported one, it makes for an interesting question. It's possible the entanglement would be broken. Or it could just be that you just add an overall phase to the correlation. IOW, if you had a superposition of ground and excited state, if your proper time shifted the right amount, the correlation would change so that they were both excited or both ground when measured. Wait longer, and it's back to one of each.

During a teleportation error there is no chance of two captain kirks existing at the same time with opposite behaviour.

On the link above Handy andy posted it refers to multiple quantum clocks being entangled to create an even more accurate clock. I understood once particles are entangled they could be moved apart and remain entangled. I don't understand your last paragraph, are you saying they would stay entangled and tick at the same rate or stop being entangled and tick at different rates

2 minutes ago, Strange said:

 

It seems to be pure speculation by Itoero.

Now I don't know what to think.

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1 hour ago, interested said:

During a teleportation error there is no chance of two captain kirks existing at the same time with opposite behaviour.

Quantum teleportation has nothing to do with Star Trek, which is science fiction.

1 hour ago, interested said:

On the link above Handy andy posted it refers to multiple quantum clocks being entangled to create an even more accurate clock. I understood once particles are entangled they could be moved apart and remain entangled. I don't understand your last paragraph, are you saying they would stay entangled and tick at the same rate or stop being entangled and tick at different rates

The  clocks in the synchronization proposal are not moving. A moving clock ticks slower than a stationary one.

further, that synchronization proposal makes some aggressive assumptions. I recall talking with a presenter at his poster at an atomic physics conference a few years back. It includes some very idealized steps, which we are nowhere close to achieving.

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On 20/08/2017 at 4:46 PM, swansont said:

Quantum teleportation has nothing to do with Star Trek, which is science fiction.

The  clocks in the synchronization proposal are not moving. A moving clock ticks slower than a stationary one.

further, that synchronization proposal makes some aggressive assumptions. I recall talking with a presenter at his poster at an atomic physics conference a few years back. It includes some very idealized steps, which we are nowhere close to achieving.

I think we covered the star trek thing on an earlier post.

The clocks may not be moving, but are separated, to separate them you have to move them apart.

No one has addressed my question ref ehow far apart objects can be to entangle them, except by your teleportation idea, which is not the same as entanglement of atomic clocks.

I will see what I can throw up using google, I may have better luck, thanks any way.

On 20/08/2017 at 3:18 PM, Strange said:

I just read through to the end of this. "Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model." Yeuch. They haven't thrown out the Big Bang model. The Big Bang model describes how the universe evolves from an early hot dense state. They haven't challenged that at all.

I would take everything Itoero posts with a large pinch of salt.... (And I wouldn't trust everything I say, either. I am often wrong!)

Itoeros post was incredibly more detailed than your post. You may both be wrong.

I am not going to get involved in an argument so will revert to google and check out both your claims.

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16 minutes ago, interested said:

The clocks may not be moving, but are separated, to separate them you have to move them apart.

But if you synchronize them after you've moved them then the motion isn't an issue.

Quote

No one has addressed my question ref ehow far apart objects can be to entangle them, except by your teleportation idea, which is not the same as entanglement of atomic clocks.

Teleportation is how you synchronize the clocks with entanglement.

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Let me see if I can clarify...

Take a coin. It is one piece, and described by the same properties, although it has a 'heads' and 'tails'.
I now cut the coin along the plane, so that one piece shows 'heads', and the other piece shows 'tails'.
I now put each piece in an envelope and give you, Interested, one envelope, and Itoero, the other.

Neither of you knows what is in your envelope, but as soon as either of you opens your envelope and you see ' heads' or 'tails', you immediately know that the other has the opposite in his envelope.
No actual information ( or data ) has been sent anywhere ( nor through wormholes ).
And do you think it makes any difference how far apart you and Itoero get ?

Edited by MigL
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18 hours ago, Mordred said:

Turns out I may be wrong on that according to this paper

https://arxiv.org/abs/1210.5555

Fascinating (I had also assumed that only identical particles could be entangled).

Here's another example:

"Quantum entanglement between a single photon and a trillion rubidium atoms"

https://m.phys.org/news/2017-03-quantum-entanglement-photon-trillion-rubidium.html

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53 minutes ago, swansont said:

How does one entangle the deBroglie wave?

I don't know. But isn't a debroglie wave a common property for bosons and fermions? You need a common property to get entangled. Or maybe the answer lies in the angular momentum...electrons can get spin-entangled.

Edited by Itoero
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1 hour ago, Strange said:

Fascinating (I had also assumed that only identical particles could be entangled).

Here's another example:

"Quantum entanglement between a single photon and a trillion rubidium atoms"

https://m.phys.org/news/2017-03-quantum-entanglement-photon-trillion-rubidium.html

 

Yeah It surprised me as well when I decided to double check my original response.

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4 hours ago, Itoero said:

I don't know. But isn't a debroglie wave a common property for bosons and fermions? You need a common property to get entangled. Or maybe the answer lies in the angular momentum...electrons can get spin-entangled.

How would you spin-entangle a boson and a fermion?

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1 hour ago, swansont said:

How would you spin-entangle a boson and a fermion?

It doesn't explain the process but Strange's link is very interesting and shows you can entangle a boson with fermions.

"In the Quantum Memory Laboratory at the University of Warsaw, the group of three physicists was the first to create such an entangled state, which consisted of a macroscopic object—a group of about one trillion atoms, and a single photon. "Single photons, scattered during the interaction of a laser beam with atoms, are registered on a sensitive camera. A single registered photon carries information about the quantum state of the entire group of atoms. The atoms may be stored, and their state may be retrieved on demand," says Michal Dabrowski, Ph.D. student and co-author of the article."

Mordred's link."we report an all optical experimental demonstration of quantum entanglement between a single electron spin confined to single charged semiconductor quantum dot and the polarization state of a photon"

Edited by Itoero
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How does the spin of a Boson with integer spin transfer to a fermion with 1/2 spin, Is the spin transferred to 2 fermions?

I have not been able to find any good explanations of how entanglement is carried out other than the pop science stuff, is there a technical link someone could provide to how entanglement is carried out.?

Edited by Handy andy
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