What is the maximum speed of information?

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Offline Airthumbs

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What is the maximum speed of information?
« on: 11/01/2011 23:42:51 »
If information can travel faster then the speed of light, does it have a limit as that of light?
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Offline QuantumClue

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« Reply #1 on: 11/01/2011 23:46:16 »
Information comes in bits, materialistic bits. Information about the system is contained within the energy or matter a system is made of. Information therefore cannot travel faster than light. Though Doctor Fred Alan Wolf if I recall, believed that ethereal information can travel faster than light.

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Offline Airthumbs

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« Reply #2 on: 12/01/2011 00:00:52 »
I was referring to an EPR paradox, in this case the entanglement of two separated particles and observing their quantum states.  Although I see that this is instantaneous I am wondering if that over huge distances this effect has a speed limit.
Also the information I am referring too is the information passed between to two particles upon observation of one of them.
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Offline JP

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« Reply #3 on: 12/01/2011 04:14:10 »
The usual definition of information is in terms of bits, as quantumclue said.  In quantum mechanics, you can send information by preparing a quantum particle in different states, so that each state represents information.  Entanglement basically involves forcing two particles to be related in such a way that changing one of them (by measuring it) changes the one on the other end, so you can send something between the two particles.

The problem comes when you try to actually send usable information that way.  It turns out the person on the receiving end has to get some additional information from you before they can interpret that the quantum particle did, and this additional information is limited by the speed of light.

So in summary, there is apparently something happening faster-than-light for quantum systems, but it's not usable information as far as we know.

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By the way, Quantumclue also mentions Fred Allan Wolf.  I would recommend taking anything from Dr. Wolf with a large dose of skepticism.  He's a big proponent of quantum pseudoscience and publishes a lot of books that are very poorly regarded by mainstream science.

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Offline Geezer

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« Reply #4 on: 12/01/2011 06:06:03 »
Annoying, isn't it. If it worked, instantaneous communication would have some interesting applications.
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Offline QuantumClue

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« Reply #5 on: 12/01/2011 09:34:42 »

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By the way, Quantumclue also mentions Fred Allan Wolf.  I would recommend taking anything from Dr. Wolf with a large dose of skepticism.  He's a big proponent of quantum pseudoscience and publishes a lot of books that are very poorly regarded by mainstream science.

I don't know his work well enough of form that kind of opinion :)

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Offline Airthumbs

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« Reply #6 on: 12/01/2011 13:37:38 »
If instantaneous communications is possible using quantum mechanics then this must be a good way of chatting to aliens over huge cosmic distances.  Something is passing between the two entangled particles.  I am not quantum scientist, so I ask is it possible to have two entangled particles existing, lets say at opposite ends of the visible universe?
And also has anyone been able to identify exactly what is passing between the two particles in an entangled state?
And is it possible that we could have such systems in our brains?
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Offline syhprum

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« Reply #7 on: 12/01/2011 14:25:57 »
There is some evidence that the influence of gravity travels faster than c (see the correspondence on this forum) therefor communication via gravity waves should be able to transmit information at superluminal speed.
The problem is the technology the generation of gravity waves requires the movement of very large masses and the most sensitive receivers so far built have failed to detect any naturally occurring ones.
syhprum

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Offline QuantumClue

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« Reply #8 on: 12/01/2011 15:01:14 »
If anything there is the possibility that information tunnels. That means it removes the superluminal suspects.

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Offline Foolosophy

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« Reply #9 on: 12/01/2011 15:47:48 »
Depending on how you define information, NOT all information is discrete

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Offline imatfaal

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« Reply #10 on: 12/01/2011 16:23:13 »
To be dull and orthodox; at present gravitational waves are thought to travel at light speed per GR, and quantum entanglement cannot lead to a transfer of information. 

Admittedly there is a lot of speculation over the speed of gravitational waves - but as none have been detected, you pays your money your takes your choice over which theory you wish to follow and it needs a great argument to bypass GR.  Its by no means settled - but if you are gonna bet on a theory I would go with GR every time.

Quantum entanglement has the prospect of being able to transfer information - but at present it does not.  If you set two electrons to an entangled state and take them apart then the entanglement remains - which might be useful; but as soon as you measure one of them, or align one of them the entanglement is broken.  you can't wiggle one of the electron on earth and watch its entangled pair wiggle on alpha centuri. 
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Offline Geezer

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« Reply #11 on: 12/01/2011 18:25:17 »
I suppose it's possible to use it as a means to synchronize events at two locations.

http://www.physorg.com/news132830327.html
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Offline imatfaal

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« Reply #12 on: 12/01/2011 18:47:05 »
Thanks Geezer - just read the summary  you gave and an article in Nature by the same guy Daniel Salart.  I can't post a link to the Nature article as it is behind pay-wall - but I am sure a little google scholaring would dig it up. 

Anyone know of a nice intro to Franson Interferometry? 
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Offline yor_on

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« Reply #13 on: 13/01/2011 04:18:45 »
Yep, but that's where I wonder.
What about plants using entanglements to transfer 'energy'`? Converting it into chemical biological nourishment?

If they do so, instantly, as the term is. Then I would consider this a very 'meaningful' information. I can't see anything more meaningful in a universe in fact. And there was also a proposition on how to use 'energy' transfered to one 'entangled' particle to give his 'twin' the same amount-

That one phreaks me out totally in fact :)
If it would work you would get two 'energy quanta' out of one. Then we would have to look at a lot of ideas we take for granted, like energy conservation, and reformulate it, it seems to me?
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Offline yor_on

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« Reply #14 on: 13/01/2011 04:20:53 »
Or as I do, reformulate the concept of 'energy'.
I think that might work too?
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Offline JP

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« Reply #15 on: 13/01/2011 06:57:27 »
Yor_on, I'm unaware of cases where you can send energy through entanglement.  From what I know of entanglement, it sounds impossible.  If you have a source for plants entangling energy, that would be interesting to read, though.

If you receive an entangled particle, it's in multiple quantum states at once (as a quantum superposition).  If you measure the particle, you see only one state, though.  When you generated it, you set probabilities of seeing each one of those states.  Entanglement just means that your measurement will influence the results your friend will get upon measurement, who has the entangled partner of your particle. 

If you somehow entangle energy states, and measure a high energy state, you haven't created or sent energy--it was already in both particles.

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Offline Foolosophy

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« Reply #16 on: 13/01/2011 07:15:16 »
If anything there is the possibility that information tunnels. That means it removes the superluminal suspects.

tunneling does not imply an increase in speed or speeds in excess of the speed of light

You not only must show how the tunneling mechanism works but whether it can be detected

Otherwise we are taking about Scientific Religious dogma

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Offline Geezer

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« Reply #17 on: 13/01/2011 07:50:30 »
Who said anything about tunneling? The experiment clearly demonstrates the phenomenon. It is not required to demonstrate how the phenomenon works.
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Offline yor_on

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« Reply #18 on: 13/01/2011 09:03:02 »
JP look at this Photosynthesis.  And there was another better one one that I linked here before? Ah, here :) Chloroplasts use of entanglement's to transport solar energy and here's the PDF..Quantum entanglement in photosynthetic light harvesting complexes.
==

Although i might jump to conclusions here I get the impression that it works?

"Researchers are increasingly trying to peek inside nature’s bag of tricks and develop a new generation of biologically-inspired photovoltaics. Two recent discoveries represent significant progress toward this goal. The first of these papers  was from a group of UC Berkeley researchers, led by chemistry professors Graham Fleming and Birgitta Whaley. They demonstrated that chloroplasts make use of a quantum physical effect known as entanglement to transport solar energy from light harvesting pigments to chemical reaction centers with extraordinary efficiency. Entanglement causes pairs of electrons that are spatially separated to behave like a single particle, meaning any change to one electron instantaneously affects the other. In plants, this effect allows solar energy to be stored in a high-energy electron configuration for a long enough period of time to be transferred to the chemical reaction centers before any of the energy has a chance to leak away."
==

And this is also what I'm talking about when I say I saw a proposition testing just this, to send 'energy' over a entanglement boosting one photon. I don't have the link to that one though, but I'm sure I put it up, somewhere? :)
==

"The second recent innovation, made by a group led by Professor Michael Strano at MIT, is an artificial light-harvesting structure  that has the ability to reassemble after its molecules have been broken apart by light. This mimics the mechanism used by plants to combat gradual reductions in conversion efficiency over time. In plants, proteins in the light harvesting regions typically break apart and reassemble every 45 minutes, a process that maintains the health of the system year after year. Similarly, damaged structures in the MIT group’s concoction reassemble whenever a surfactant is added to and subsequently removed from the solution. Thought to be the most complex man-made self-assembling system ever developed, their structure consist of seven different compounds, including carbon nanotubes, proteins, and phospholipids. Although their device isn’t quite ready yet to compete with silicon-based solar cells, their work represents the first step towards developing long-lasting, low-cost solar cell materials using nature’s own self-repairing approach."
==

But yes, you're correct in that it has to be injected somehow without measuring, I wish i had that link I'm talking about. In it I think they suggested some way, although thinking of it? It would have to be very weird to work. Da*n :)

I kind'a liked it..
The idea :)
« Last Edit: 13/01/2011 09:21:30 by yor_on »
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Offline lightarrow

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« Reply #19 on: 13/01/2011 09:16:31 »
If instantaneous communications is possible using quantum mechanics then this must be a good way of chatting to aliens over huge cosmic distances. 
No, there is no relation between the two things. In QM what is "istantaneous" or however, very fast, cannot be properly called "communication".
Anyway, transmission of information faster than c is not possible.

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Offline yor_on

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« Reply #20 on: 13/01/2011 09:28:12 »
Okay doubters worldwide :)

I found it.
==

And I was wrong. It seems pretty straightforward to me, the concept? But if it works it will give me a headache :). I have no problem with 'energy' being a relation and not its own 'thingie'. But if this works you will have to question the conservation of energy it seems to me??

"In quantum energy teleportation, a physicist first makes a measurement on each of two entangled particles. The measurement on the first particle injects quantum energy into the two-particle system, which is possible because there are always quantum fluctuations  in the energy of any particle. This energy can then be immediately extracted at the second particle by making a second carefully chosen measurement on that particle. Throughout the process, the energy of the overall system remains the same. "

Sounds very much like those clever sales "Get two to the price of one!" And that gives me a headache.
==

And here is the preprint Energy-Entanglement Relation for Quantum Energy Teleportation by Japanese physicist Masahiro Hotta of Tohoku University.
« Last Edit: 13/01/2011 09:43:07 by yor_on »
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Offline yor_on

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« Reply #21 on: 13/01/2011 09:59:20 »
And as long as we're on it..

Sorry, will try to find something you can read without being subscribed.
Una momento.

Okay here is the original paper. the joint winner of the Nobel Prize for medicine in 2008, Luc Montagnier is claiming that DNA can send 'electromagnetic imprints' of it self into distant cells and fluids which can then be used by enzymes to create copies of the original DNA. Meaning Quantum teleportation.

But I still find the 'energy idea above this even more surprising :)
And this idea is not a happy camper. A lot of scientific flack hammering this one :)
==

Maybe 'Quantum teleportation' is a little to much though?
Don't know what he means actually?

He seems to have a history of ah, surprising ideas :) Which is good in one way, bad in another. It's good to have ideas, but if you're trying to push them as being the certified truth? Then we get into another shoe altogether as you English say, or don't say? See if I care huh :)

Take a look Here. 2009

==

Eh, this is not mine but do I wish :)

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« Last Edit: 13/01/2011 11:49:16 by yor_on »
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Offline lightarrow

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« Reply #22 on: 13/01/2011 16:52:57 »
"In quantum energy teleportation, a physicist first makes a measurement on each of two entangled particles. The measurement on the first particle injects quantum energy into the two-particle system, which is possible because there are always quantum fluctuations  in the energy of any particle. This energy can then be immediately extracted at the second particle by making a second carefully chosen measurement on that particle. Throughout the process, the energy of the overall system remains the same. "
Ok, but it's impossible to know "a priori" the result of the measurement on the first particle, so you don't know "a priori" which amount of energy will be teleported in the other, so you cannot send information in this way.

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Offline yor_on

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« Reply #23 on: 13/01/2011 18:05:53 »
Maybe not, to me it depends on what one consider 'meaningful information' to be. For me , if now a plant get something out of 'energy', I would consider that to have to be seen as 'information' too. To me it makes it a da*n bit (no pun intended) more important than 'qbits'. As it actually is seen to work on a practical plane. If I got it right that is :)
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Offline Airthumbs

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« Reply #24 on: 13/01/2011 19:01:34 »
But you can easily send information using two entangled particles!!  You just have to have the language sorted out before you attempt anything. 

Ok lets say one wiggle is a 0 and two wiggles is a 1.   Using this technique you would have binary code. 

From what I understand, if one of these particles is made to rotate clockwise then the other entangled particle will have to be rotating the opposite way. 

Of course if I am wrong and I may well be then none of the above would work!  [:o]
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Offline lightarrow

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« Reply #25 on: 13/01/2011 20:19:37 »
Of course if I am wrong and I may well be then none of the above would work!  [:o]
Correct  [:)]

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Offline Geezer

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« Reply #26 on: 13/01/2011 20:42:34 »
Of course if I am wrong and I may well be then none of the above would work!  [:o]
Correct  [:)]

Ah yes, but if you were to send a continuous stream of entangled particles from A to B and C, you could use a sort of Morse Code that was based on whether you measured them or not - maybe?
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Offline QuantumClue

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« Reply #27 on: 13/01/2011 21:56:29 »
Geezer

You asked how tunneling entered the discussion early on. That was me.

The reason why something tunnels, as I am sure you may be aware, is because some kind of ''hill'' stands between an efficient trajectory of a particle. The hill is a steep potential, and it costs less energy to tunnel this barrier rather than travel the whole deal. In much the same sense, a high potential is created when talking about information sharing over very large distances. To avoid the trouble of contradicting SR postulates, it may be best to imagine information being forced to tunnel large distances, rather than allowing it to travel it at superluminal speeds.

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Offline Geezer

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« Reply #28 on: 13/01/2011 22:05:49 »
Geezer

You asked how tunneling entered the discussion early on. That was me.

The reason why something tunnels, as I am sure you may be aware, is because some kind of ''hill'' stands between an efficient trajectory of a particle. The hill is a steep potential, and it costs less energy to tunnel this barrier rather than travel the whole deal. In much the same sense, a high potential is created when talking about information sharing over very large distances. To avoid the trouble of contradicting SR postulates, it may be best to imagine information being forced to tunnel large distances, rather than allowing it to travel it at superluminal speeds.

Thanks QC. Yes, that does make sense and it might well explain what's going on, not that I can understand it or anything!
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Offline QuantumClue

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« Reply #29 on: 13/01/2011 22:24:56 »
Of course, this depends if our universe really does have a description of nonlocality. To be honest, I'm not even sure how to visualize something complex like nonlocality. Surely however, if nonlocality exists, it is not safe to call the universe purely nonlocal in nature. In all reasoning, the universe must be local and nonlocal depending on what circumstances of a system is brought to attention. Locality cannot simply die as a true definition of certain systems in light of a nonlocal attribute.

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Offline JP

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« Reply #30 on: 14/01/2011 01:40:51 »
There were some experiments done by a fellow named Gunther Nimtz on the speed of tunneling photons.  He claims to have seen them moving faster than light, but it's a bit controversial at the moment, since no one's reproduced it, and obviously this kind of claim has to be checked very carefully.

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Offline yor_on

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« Reply #31 on: 14/01/2011 01:52:57 »
But you can easily send information using two entangled particles!!  You just have to have the language sorted out before you attempt anything. 

Ok lets say one wiggle is a 0 and two wiggles is a 1.   Using this technique you would have binary code. 

From what I understand, if one of these particles is made to rotate clockwise then the other entangled particle will have to be rotating the opposite way. 

Of course if I am wrong and I may well be then none of the above would work!  [:o]

The problem is how to make the code make sense :)

You could possibly send entangled photons like we've done in some experiments, but first you will have to send the decoder, and that you will need to do at under light speed. It would not be smart to send that by the same entanglements. The other restriction is in one photons spin per 'bit of information' and you will need a lot of those to tell which letter you mean. so assuming that you sent someone away he will need to store an awful lot of entangled photons for an awful long time before needing them, as he moves under light speed. On the other hand you then have solved the 'decoder' problem as you gave it to him before he left your planet.

The other way is to send 'entangled photons' on their own, then they will move at 'c' but not faster to whatever destination. And you still need to send a 'code book'. The third way is to assume that all light might be entangled some way? Then I think someone would have used it already to give us improbable spins when measuring. That would be one way to 'communicate' even if not making 'sense' as we have no 'codebook'.
=

Another thing, when measuring a spin you can't know before how it will fall out for you. That the opposite spin gets created doesn't mean that you would know which type of spin it was. Assume then a order of photons in a row where the information depend on which photon change spin for you, at what position in that row, at that star. But how would you ever know that one of them had changed 'spin'? Without measuring them?

And when you do you destroy it. The spin I mean, you 'set' it as you measure.
« Last Edit: 14/01/2011 02:07:56 by yor_on »
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Offline Geezer

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« Reply #32 on: 14/01/2011 06:24:28 »

You could possibly send entangled photons like we've done in some experiments, but first you will have to send the decoder, and that you will need to do at under light speed. It would not be smart to send that by the same entanglements. The other restriction is in one photons spin per 'bit of information' and you will need a lot of those to tell which letter you mean. so assuming that you sent someone away he will need to store an awful lot of entangled photons for an awful long time before needing them, as he moves under light speed. On the other hand you then have solved the 'decoder' problem as you gave it to him before he left your planet.

The other way is to send 'entangled photons' on their own, then they will move at 'c' but not faster to whatever destination. And you still need to send a 'code book'. The third way is to assume that all light might be entangled some way? Then I think someone would have used it already to give us improbable spins when measuring. That would be one way to 'communicate' even if not making 'sense' as we have no 'codebook'.
=

Another thing, when measuring a spin you can't know before how it will fall out for you. That the opposite spin gets created doesn't mean that you would know which type of spin it was. Assume then a order of photons in a row where the information depend on which photon change spin for you, at what position in that row, at that star. But how would you ever know that one of them had changed 'spin'? Without measuring them?

And when you do you destroy it. The spin I mean, you 'set' it as you measure.

I've really no idea if this would work, but I suspect the only option is to have two "stores" of entangled photons at both ends. You sort of have to take them with you, otherwise it could be a bit pointless.

Then, assuming you can figure out some method of encoding a message (which may well be impossible), you have the problem that the store is finite, so once you've depleted the store, you can no longer communicate until you get a "refill" at, or less than, light speed.
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Offline JP

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« Reply #33 on: 14/01/2011 06:56:02 »
It's a bit beyond me to come up with a general proof that entanglement can't send information faster than light.  I don't know if anyone can do that, actually.  I do know that every attempt to come up with an FTL-transfer scheme based on entanglement apparently fails to actually send information until a classical channel is opened up.

If someone wants to take a stab at proposing a method for an FTL information transfer based on entanglement, maybe we can show why it can't work...

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Offline Geezer

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« Reply #34 on: 14/01/2011 07:40:11 »
It's a bit beyond me to come up with a general proof that entanglement can't send information faster than light.  I don't know if anyone can do that, actually.  I do know that every attempt to come up with an FTL-transfer scheme based on entanglement apparently fails to actually send information until a classical channel is opened up.

If someone wants to take a stab at proposing a method for an FTL information transfer based on entanglement, maybe we can show why it can't work...

Good idea. Let's see if this can survive for a couple of picoseconds:

Assuming you and I have very large photon stores, as previously mentioned, if you are reading your store at the same time as I am - nope! That's not going to work.

The problem seems to be that, as we can't know what the sequence is in advance, we can only prove that we were "communicating" by comparing our results after the fact. Is that about right?

Or, it's as if we both have an envelope that contains the same random number. I can alter your random number when I read my copy, but, because you cannot know what the original number was, you have no way of knowing whether I changed it or not.
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Offline Geezer

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« Reply #35 on: 14/01/2011 08:11:44 »
Soooo, if that's true and we have multiple envelopes containing numbers that actually have some sort of statistical bias, that would allow me to read my envelopes in a way that either increased, or decreased, that bias, which you should be able to detect as a form of Morse Code.

However, if it's not possible to create envelopes with biased numbers, it's not going to work. 
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Offline JP

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« Reply #36 on: 14/01/2011 08:33:24 »
Exactly!  The random-envelope situation is the exact problem with the simple setup for sending information via entanglements.  The numbers I read appear random, regardless of what you've done.  It's only when you send some light-speed information that I know whether you've measured or not.

I don't think there's a way to create bias with measurements alone--at least I can't think of a simple way to do it, and I presume if there was, someone would have come up with it already.

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« Reply #37 on: 14/01/2011 08:37:09 »
But the random-envelope case also shows a really good use of quantum entanglement: cryptography.  If I want to send you a coded message, I first need to come up with a secure key and send it to you.  If I sent you a bunch of entangled particles, then I measure them, I'm determining a random key that we both will agree on. (The actual algorithms are more complicated, since they involve ways of detecting eavesdropping, which effects the quantum statistics between entangled particles.)

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« Reply #38 on: 14/01/2011 10:13:03 »
JP when you let a photon into a condense, 'stopping it'? Do one set the spin then too? Or can I look at that as something not interfering with the photons superposition?

Myself i have this feeling that as soon as one 'touch it' in any way the spin must be set, no matter if you measure it or not. On the third hand that would mean that  I've now 'interacted' with it, without destroying it, if so? Nah, It gotta be superpositioned even after you slowed it down. Or I will have to rethink what an 'interaction' means.
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« Reply #39 on: 14/01/2011 11:03:37 »
Usually "slowing it down" implies not destroying the superposition. 

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« Reply #40 on: 14/01/2011 16:49:15 »
There were some experiments done by a fellow named Gunther Nimtz on the speed of tunneling photons.  He claims to have seen them moving faster than light, but it's a bit controversial at the moment, since no one's reproduced it, and obviously this kind of claim has to be checked very carefully.

Fascinating.

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« Reply #41 on: 14/01/2011 20:57:36 »
Ok, so instead of rotating the entangled particles why not make one of them positive, this would mean the other has to be negative? 

And then instead of using just a pair of entangled particles to try and transmit, you could use literally millions of them allowing complex transmission and receivers. 

Has anyone discovered what exactly is the information that passes between the two entangled particles?  Something is transmitted and whatever that is moves significantly faster then the speed of light.  You might even say that the speed is infinite?  So maybe the maximum speed of information in this context is infinity? What I find fascinating is that there appears to be some kind of force capable of traversing the entire universe instantaneously!

If there is a way to identify exactly what this is and investigate it then we might have a way to talk to the stars  [;D]
You can tunnel, dig, fold, or even worm your way through space so why not just ignore it all together, something does!
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« Reply #42 on: 14/01/2011 21:16:10 »
Ok, so instead of rotating the entangled particles why not make one of them positive, this would mean the other has to be negative? 

And then instead of using just a pair of entangled particles to try and transmit, you could use literally millions of them allowing complex transmission and receivers. 

Has anyone discovered what exactly is the information that passes between the two entangled particles?  Something is transmitted and whatever that is moves significantly faster then the speed of light.  You might even say that the speed is infinite?  So maybe the maximum speed of information in this context is infinity? What I find fascinating is that there appears to be some kind of force capable of traversing the entire universe instantaneously!

If there is a way to identify exactly what this is and investigate it then we might have a way to talk to the stars  [;D]
You can tunnel, dig, fold, or even worm your way through space so why not just ignore it all together, something does!

Well, we just don't know do we :)

It's probably a safe bet to say that whatever it is, it is not a physical transaction. Whatever it is, Bells Theorem has, and I qoute:

''In conjunction with the experiments verifying the quantum mechanical predictions of Bell-type systems, Bell's theorem demonstrates that certain quantum effects travel faster than light and therefore restricts the class of tenable hidden variable theories to the nonlocal variety.''

http://en.wikipedia.org/wiki/Bell's_theorem

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« Reply #43 on: 14/01/2011 21:19:16 »
Ok, so instead of rotating the entangled particles why not make one of them positive, this would mean the other has to be negative?

Sadly, it would not make any difference. The root of the problem is that you can't influence the "direction" of the entanglement during the entanglement process. You are creating a random number when what you really want to do is create a nonrandom number, but that's not possible.

Think of it this way. You need a way to load the dice. Unfortunately, you can't ever get you hands on them. Not only that, you can't even look at them in advance, so you have no prior knowledge of the random number that was generated.
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« Reply #44 on: 14/01/2011 21:36:02 »
Wait a minute!

If we didn't know what the random number was in the first place, how do we know all this measuring palaver is doing a dang thing?
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Offline imatfaal

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« Reply #45 on: 14/01/2011 21:45:29 »
Because even though you have separated in space the entangled particles continue to produce the same interference/random number/measurement.  Per the experiment you posted yesterday - the photons interfered although geographically remote to an extent that any communication between them would have to be superluminal.  the entangled photons caused the same macroscopic events to occur - and to show that no lightspeed particle had conveyed a signal from one to the other - the two sites were placed far enough apart that both macroscopic events would have completed before any lightspeed particle/information would have time to bridge the gap.   
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« Reply #46 on: 15/01/2011 00:30:49 »
Thanks Matthew. That's not what I was concerned about. I'll have to read up on the measuring process again. I suspect I'll find the answer there.

What I'm wondering is, could the pair be "fooling" us into thinking that they are interacting superluminally as a result of our measuring when they are actually ignoring us, so to speak. If we knew a state before we measured it, we would know for sure, but we can't do that. I'm sure there's a good answer though.
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« Reply #47 on: 15/01/2011 01:55:49 »
Geezer

I cannot help but read this last one as invoking perhaps some kind of determinism, is this what you are hinting at?

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« Reply #48 on: 15/01/2011 02:47:55 »
Geezer

I cannot help but read this last one as invoking perhaps some kind of determinism, is this what you are hinting at?

I wouldn't really know [;D] but I don't think that's what I mean to imply. I'm wondering if there could be some sneaky false assumption in the logic, although I can't imagine how that would get past so many clever scientists. I asked the question more because I don't fully understand it myself than as a direct challenge to the experiment.

However, as you bring it up, if there was some sort of determinism at play, would the experiment point to that as a possible explanation?


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« Reply #49 on: 15/01/2011 03:42:51 »
Geezer, check this post and the one I make following it.  It's a description of the unique statistics of entanglement in one case.  It might help clear things up.  Then again, it might not.  :)

There are also more general proofs (Bell's inequalities) that quantum entanglement generates unique statistics that can't be generated by "hidden variables," i.e. that the numbers aren't set up with local variables that let them decide to agree without having to communicate something to each other instantly.  If you Google for tests of Bell's inequality, you'll find plenty of experiments testing this and finding that entanglement is not generated by hidden variables.