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Author Topic: Have they really acheived instantaneous transmission of information?  (Read 9967 times)

Offline DoctorBeaver

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Researchers have accomplished teleportation, though not of the “Beam me up, Scotty” variety. Instead, they sent information between two individual atoms of the element ytterbium, which were suspended in separate containers three feet apart. Because the quantum information instantly hops from one atom to the other without ever crossing the space between the two, scientists call the transfer “teleportation”

Extract from http://blogs.discovermagazine.com/80beats/2009/01/23/quantum-teleportation-is-a-go/

Anyone got any thoughts on this?


 

Offline Vern

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I have often speculated that atoms transfer photons among each other by first sensing a suitable receiver then when one is found, the actual transfer is instantaneous. The advertising for a suitable receiver is bound by the speed of light.

Such speculation comes while contemplating Schrodinger's Cat.

This could be tested if it could be determined whether a neutron would delay its demise if there were not suitable receptors for the energy it must release to do so.
« Last Edit: 24/01/2009 15:01:50 by Vern »
 

Offline DoctorBeaver

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This could be tested if it could be determined whether a neutron would delay its demise if there were not suitable receptors for the energy it must release to do so.

Interesting
 

Offline Vern

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This could be tested if it could be determined whether a neutron would delay its demise if there were not suitable receptors for the energy it must release to do so.
Interesting
An easier test to devise might be to see if a neutron would decay more rapidly with an excess of suitable recptors available. That might be easier than restricting them.

I've looked back through bubble chamber results with this mindset, but so far haven't found suitable evidence.

Edit: However we do know that the act of observing can change how a system reacts; the act of observing must provide suitable receptors for the observation.
« Last Edit: 24/01/2009 15:21:34 by Vern »
 

Offline yor_on

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Notice this "The wavelengths, or colors, of these photons depended on which states the electrons were in. Crossing these photons in a beamsplitter sometimes entwined the states of those electrons, a bizarre quantum phenomenon called entanglement "

What they seem to do is not to 'communicate' with the atom directly but to first 'force' it into a indeterministic 'state' then they give it a 'energy boost' to free one photon each which when subsequently observed will 'lock' the atoms states.

So in this experiment? 'time' have no 'meaning' at all if they are correct.
It doesn't 'back up' it doesn't move forward.

'Times' 'now' belongs both to the the interaction with the photons as well as with the atoms later 'defined states' as seen from the observers frame of reference.
Don't forget that the macroscopic arrow of time are at work for the observers of this experiment.

Either this 'entangled' state is  there a soon those two photons are released, before observed, or it is created only in the observing.

But seen from the observers frame of reference time will have an arrow and if the experiment could be seen as creating entanglement before observation then we are 'isolated' from influencing the outcome.

But as they can't, as I've understood it, define what spin the ion would have before observing?
I can't see how they think to transfer information by it??
As the spin will be aleatory (depending on 'chance') every 'time'?
 

Offline Vern

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Very interesting thoughts yor_on. I'll dwell upon them some.
 

Offline yor_on

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Thanks Vern.
I had a weak hope that this might be such an experiment wherein one would be able to observe a macroscopic 'backlog' of time as compared to the 'now' of the enanglement.
As that would make my ideas about 'time' seem more plausible:)

And I don't see it as a teleportation, I think it's a symmetry 'defined' by those mysterious rascals, the timeless photons but without our macroscopic arrow of time.
Therefore there can't be any 'information' exchanged.

Information has a beginning and a end. It's like a flow of water, and if you want it to go both ways you will need to 'pipe' it two ways, and for that you will need to apply some 'work'.
And 'work' seems to be a definition of our macroscopic reality, or am I wrong there?
A lot of the things we take for 'granted' macroscopically seems to lose their 'direction' when observed at a QM level.

Don't take me to seriously now:)
 

Offline Vern

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Researchers have accomplished teleportation, though not of the “Beam me up, Scotty” variety. Instead, they sent information between two individual atoms of the element ytterbium, which were suspended in separate containers three feet apart. Because the quantum information instantly hops from one atom to the other without ever crossing the space between the two, scientists call the transfer “teleportation”

Extract from http://blogs.discovermagazine.com/80beats/2009/01/23/quantum-teleportation-is-a-go/

Anyone got any thoughts on this?
After going through the data several times I still haven't determined how they discover that the two ions are entangled. I guess one would need to study the original paper to fully understand.
 

Offline Vern

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Quote from: yor_on
And I don't see it as a teleportation, I think it's a symmetry 'defined' by those mysterious rascals, the timeless photons but without our macroscopic arrow of time.
Therefore there can't be any 'information' exchanged.
Yes; it seems that you can't know the state of both ions. They look at the state of one and assume that because they are entangled, the other is the same state. I was trying to understand how it was that they determined that the ions were entangled.
 

Offline yor_on

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It is a good question.

They need to test both ions to be sure that they do have a entanglement.

---------
So?
Is there anyone here that could give us a definition of that:)
« Last Edit: 24/01/2009 17:47:19 by yor_on »
 

Offline Vern

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Quote from: yor_on
So?
Is there anyone here that could give us a definition of that:)
I have studied entanglement in photons; I always speculated that it was simply a state of photons that share the same EM fields. I visualize photons as saturated points surrounded by fields that extend outward forever diminishing in amplitude with distance. The observation that when you change the state of one the other automatically assumes that changed state results from the way you change the state of the one. You must change its polarization. Polarization is a measure of the photon's fields, which in entangled photons is the same fields for each photon.

It is long winded and speculative; and I will change my mind easily if I see a better view.
 

Offline LeeE

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Although the article says that the main problem is basically just to do with aiming the photons there are a couple of other issues that need to be remembered.  The first is that the state in to which the system resolves cannot be specified, so you couldn't use this technique to send a specific sequence of values; the sequence would be random.  The second is that the state can't be examined without resolving it; the receiver would need to know that the sender has resolved their state before they [the receiver] examined their state, otherwise instead of the sender sending their state to the receiver, the receiver is sending their state to the sender.
 

Offline yor_on

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Yep LeeE.
:)
 

Offline Vern

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Quote from: LeeE
The second is that the state can't be examined without resolving it; the receiver would need to know that the sender has resolved their state before they [the receiver] examined their state, otherwise instead of the sender sending their state to the receiver, the receiver is sending their state to the sender.
Interesting; it seems that maybe two way communication might happen if the sender and receiver could synchronize their observations just right.
 

Offline LeeE

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Quote from: LeeE
The second is that the state can't be examined without resolving it; the receiver would need to know that the sender has resolved their state before they [the receiver] examined their state, otherwise instead of the sender sending their state to the receiver, the receiver is sending their state to the sender.
Interesting; it seems that maybe two way communication might happen if the sender and receiver could synchronize their observations just right.

I can't see how that could work because it would need to be resolved in to two simultaneous states, which is a sort of contradiction in terms.  Also, how would you achieve syncronisation between the two parties?  You're back to light-speed limits again.
 

Offline Vern

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Quote from: LeeE
I can't see how that could work because it would need to be resolved in to two simultaneous states, which is a sort of contradiction in terms.  Also, how would you achieve syncronisation between the two parties?  You're back to light-speed limits again.
Yes it would be problematic. I was thinking that slight changes (delay) in the observation ticks might put you in the receiving or sending mode. But then I don't know how you could know which mode you were in.
 

Offline yor_on

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I don't think you will be able to send any information if you can't decide/lock the 'spin' before 'observing' it?
But if you could find out the 'spin' in advance, without observing, you would still need to reach a 'consensus' on that with your friends at Betelgeuse:)

And that 'consensus' would still need to be transmitted at lightspeed:)
Both ways::))
 

Offline LeeE

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How could you know it's state without observing it?
 

Offline Vern

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How could you know it's state without observing it?
I haven't got that figured out :) Maybe why we still communicate at light speed.
 

Offline LeeE

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Quote
Maybe why we still communicate at light speed

Yup, I reckon.

Having thought about this a bit more though, there is one aspect about this that I've realised that I'm not sure about.  Does resolving the sender system actually resolve the receiver system, or does it just restrict the possible state of the receiver system so that when it's eventually resolved it can only resolve in to one possible state, dictated by the outcome of resolving the sender system?

Does anyone actually know the answer to this for sure?
 

Offline Vern

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I sure don't know the answer.
 

Offline JP

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Does resolving the sender system actually resolve the receiver system, or does it just restrict the possible state of the receiver system so that when it's eventually resolved it can only resolve in to one possible state, dictated by the outcome of resolving the sender system?

Is there a measurable difference between these two outcomes?  Philosophy aside, QM is about predicting the values of measurements.  It seems to me that in both cases, you know with 100% certainty that the measurement has to give you the resolved state.
 

Offline LeeE

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What I was wondering about is that it's the act of measuring the state that resolves the state, as I understand it.  So although the first system may have been measured, and as a consequence, had it's state resolved, the second system has not yet been resolved and it will not be resolved until measured, at which point it can only resolve in to one possible state because of the entanglement.  Thus it is only the possible state for the second system that is conveyed instantly.
 

Offline yor_on

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What I was wondering about is that it's the act of measuring the state that resolves the state, as I understand it.  So although the first system may have been measured, and as a consequence, had it's state resolved, the second system has not yet been resolved and it will not be resolved until measured, at which point it can only resolve in to one possible state because of the entanglement.  Thus it is only the possible state for the second system that is conveyed instantly.

If you find the answer to that one I would love to hear it LeeE.
And I think it should be worth a Nobel price:)

I should know.
I'm a Swede::))
 

Offline Chemistry4me

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I should know.
I'm a Swede::))
And what is that supposed to mean? Are you getting complacent yor_on?
 

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