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Published online 13 August 2008 | Nature | doi:10.1038/news.2008.1038
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Physicists spooked by faster-than-light information transfer
Quantum weirdness even stranger than previously thought.
Two photons can be connected in a way that seems to defy the very nature of space and time, yet still obeys the laws of quantum mechanics.
Physicists at the University of Geneva achieved the weird result by creating a pair of ‘entangled’ photons, separating them, then sending them down a fibre optic cable to the Swiss villages of Satigny and Jussy, some 18 kilometres apart.
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There was no FTL information transfer. The wavefunction instantaneouly collapsed into an observable, by the book, sourcing consistent data. Information existed only after opposite ends compared datasets - and that transmission happens no faster than lightspeed. Viewing one dataset allows no conclusions to be drawn. It won't even do FTL Morse code. The universe is causal.
I agree with "Uncle Al". Correlations yes, information no. To truly have faster than light information transfer one would be able to send a message for village A to village B at faster than light but even quantum mechanics rules this out.
In case of light the wave nature and the particle nature can't be separated. But yes, when one form is obstructed the other form takes its way and in this mission information is carried on even when wave nature of light is dead for that period of time. But again particle generates its co - brother after crossing the hurdle and thus the story seems impossible. Regards
Before the measurement the positions of the photons in space are not defined, thus the distance between them also makes no sense and without distance one cannot really speak about the speed of information transfer. So IMO finding the properties of two entangled photons correlated is no more and no less surprising than finding the exact position of just one photon: the particle that was kind of "spread out all over space" before the measurement suddenly and instantaneously (basically "with infinite speed", if one can dare to define a notion of "speed" in this case) "gathers itself together" in one particular spot. That what quantum mechanics is all about.
Everybody seems to agree that "objective" science explicitly based on supernatural mysteries is something utterly strange: it's a much stranger doctrine than any most esoteric religion, which doesn't pretend at least to any objectivity and logic... And nevertheless it is precisely that kind of "objective" knowledge that continues to be UNIQUELY (and very generously!) supported in ALL science institutions (private initiatives including). How indeed can one have a consistent understanding of quantum particle behaviour if that huge, multi-billion enterprise cannot even say what the real, even simplest elementary particle (e.g. photon or electron) actually is, in its physical structure and dynamics, while replacing it with an abstract symbol obeying abstract, postulated (and completely "magic"!) rules? So they end up now with an explicit sectarian religion called "mathematical universe" and supported by the dominating establishment priests from all the great faculties... Realistic alternatives to that continuing math-physical delirium certainly exist but they are rejected without discussion by the dominating, effectively totalitarian regime (Peer Review and Co.). So when Gisin allegedly "hopes that the work will stimulate theorists to come up with new ways of explaining the spooky effect", he is "slightly diverging from the truth" (or intentionally lying, to be exact!). As if he, or Geoff Blumfiel, or anyone else may ignore the fact that those "spooky effects" and related open trickery exist in the official science framework already for a century and nothing ever changes, despite innumerable theoretical efforts (starting already from the "great Einstein" with his unlimited staff) but always artificially reduced to a very special, now rigorously specified approach of unitary science ( http://arxiv.org/abs/0705.4562 ). See e.g. http://arXiv.org/abs/physics/0211071 , http://arXiv.org/abs/physics/0401164 for a review of fundamental physics without supernatural mysteries, a theory that is there for a decade already, quite accessible on the web and directly developing the ideas of the great Louis de Broglie who had clearly shown a way out of the spooky science impasse many years ago (see http://arxiv.org/abs/quant-ph/9911107 ), but this clearly designated "new way" (now successfully completed) remains officially ignored, for decades, despite the formally "encouraged" search for it. It is that kind of real science operation that "doesn’t make any sense, honestly" and while it senselessly persists on the background of “officially accepted†lies, no positive, fruitful and problem-solving knowledge development can restart, irrespective of explicitly proposed problem solutions and realistic, consistent and experimentally confirmed quantum-physics framework.
Why are people surprised by this when we've known for almost a century that the coherence phenomenon occurs in the waveforms of individual particles? How do we even know there are two separate particles before we detect them? We can only infer that from the state of the system before and after "entanglement". Maybe it's more accurate to think of the two "particles" as a single, larger particle with twice the mass, energy, etc., which breaks down when something interacts with it. That way, determinism and speed-of-light communication between "particles" is retained.
It's my opinion that from the frame of reference of the entangled photons, the universe collapses inwards along the axis of motion, thus rendering them connected to each other for the duration of their lifetime, which in their frame of reference is virtually zero time. This could explain how in our frame of reference they appear to influence one another at super-light speeds, while in their own frame of reference, they are only communicating at the speed of light. This effect cannot be observed with sub-lightspeed entities because it requires both entities in question to start in an infinitely compressed reference frame, which only happens at the speed of light. Kind regards, Sean Sinjin BetterHuman.org Authenticity Code: 0ab728ba-a799-4c0e-98ab-9979a475fb1b
Could it be that the process of entanglement connects the two waves of photons in one of the extra dimensions that are assumed by the string theory if one of these is large enough? the sizes of the assumed extra dimensions are not known yet, aren t they? (perhaps lhc will give a hint...) if the entangled wave of the two photons would be living on in an extra dimension (large enough) the information of beeing mesured only had to cross the distance of the extra dimension to affect the other photon. could this be or did i understand something wrong?
Mathias, I don't think you understand the idea of dimensions. You seem to think of them as other worlds with sizes. Consider the transition from 2D to 3D: we simply add a new direction. And further, if we take two points that were lying on a plane, and try to connect them by a curve that does not lie in the plane, that curve must be longer than the line segment defined by those two points. It therefore must take longer to traverse at a given speed than the segment at the same speed. Now, an interesting notion would be if our four-space were not so rigid as we might think. Picture a 2D sheet sitting in three-space, and when we entangle two photons, the sheet pinches together, so that the distance between them in three-space is nil, while the distance on the sheet can grow arbitrarily. (That is, when we move the photons, the pinch moves with them in the higher space.) Of course, I'm no physicist, and the mathematics would be beyond me, but I'd be curious as to whether that's possible. Perhaps one could test it by determining a collection of pinches that would be mutually exclusive, and seeing if the real world somehow prevented them all from occurring simultaneously.
Hi Chris! Thank you for your comment! In fact I think we mean pretty much the same talking about "extra dimensions" or as you said "higher space". Its kind of difficult to use words for things so far away like the quantum world or the relativistic one. For I am a mathematical "idiot" I hope it is even possible to use words to describe them sufficiently cause even without maths I m very interested in these kind of things. I tried to follow the lecture of Leonhard Susskind about Quantum Entaglement on Youtube but only came to session 3 till now. Wish I had a teacher like him in highschool!
I cannot support added dimensions without cause. It seems to me that the evolution of the photons is governed by their wave form, which was set to an identical state for both photons by the entanglement. Therefore the communication occurred at the time of entanglement, and what would follow was at that event set. So overall, I agree with Uncle Al: There is no FTL here, but instead just the inate wierdness of QM.
Photons have knowledge in them, when they go through our eyeballs into our brains we receive it and organize it into thought. Electricity in any form is the same and in a way it can think and anticipate, but the lower you go in scale the less it can anticipate, like just itself in this case. The Truth itself is hidden inside light. The phrase "i have seen the light" and a "lightbulb going on over your head" are foreshadowing for this. The way it works is if you line up the letters T through Z on a piece of paper you can find out how Light is Eventually turned into memory. I wrote an article about it months ago but nobody cared. I even sent it to people in the scientific communitiy. The relationship between light itself and knowledge is the answer to the 'disturbing feelings' people get in this field, because they don't want to admit that if Light was itself Intelligent there might be religious implications to it. In reality the universe around us, as shown by fibonacci sequences in all processes is itself intelligent and the only way to survive in it is to become an independent thinker, creating randomness in your mind which offsets the plan that outside influences had for you. You are all welcome and have a good day.
Before I exit the site, i'll give you an example.. light bounces off something and goes into your eyeball and you translate it into knowledge and eventually memory, but when the light bounces off that thing something happens... the light itself acquires information which it brings to you called truth, and the better you can see the light that has reflected off the event the better you can interpret reality. The thing that light bounced off of imprints the light with itself to bring to you. So when you see something beautiful, you feel truth, light is bringing it to you because the light has been imprinted with pure beauty, pure truth. That is why beauty is important to humanity, as the great poem states.
All the talk of other dimensions and hidden matter is just all the things of the universe sending light around with it imprinted with all the things it bounced off of. In effect, light that has bounced off three things is smarter than light that has bounced off two becaus it is imprinted with the truth of three things than two. If anyone has thought of this already i'll apologize in advance, but that in effect is why people studying light that hasn't bounced off of anything and in such a closed environment are so clueless, the light is missing something they seek, the truth, because it is completely isolated in these experiments... except from itself. Interesting.
Until people understand that light, like a plant in the ground, is effectly alive with pure knowledge, they will never unlock all the mysteries of the universe.
In this way orwell was right, 2 plus 2 equals 4 is not just an equation, it has philosophical properties, but since we were told in the 1990's that you won't get a job studying philosophy, people who are spending years analyzing equations never get anywhere because the importance of those equations to philosophy and vice versa are equal, and must be applied carefully.
The question, does a tree fall in a forrest if no one hears it is not yes or no.. it is that the universe wishes you heard it fall because it wants you to study it and know its beauty. Sounds sappy, but it has mathematical implications that will help the 'confusing conduct' of particles. Maybe if people thought that the world around them is as alive as they are, the human scope of understanding would expand enough to stop wars and focus only on studying and expanding that beauty.
I can't figure out why this is news. Surely the editors of nature are aware that quantum mechanics predicts violations of the Bell inequalities and that such violations have been convincingly experimentally verified by Aspect and others. Perhaps this is the first clear experimental verification of quantum non-locality that doesn't depend on statistical data about systems, i.e. it's a more like an experimental Greenberb-Horn-Zeilinger result?
Stephen - The issue is the scale over which the result holds true. I'm sure that they would get the same type of results if they bounced entangled photons off of mirrors on the Moon, but noone that I know of has done that test yet.
In my opinion, there is no contradiction between Einstein's stance that nothing can move faster than light and the instantaneous correlation between two entangled photons. There is only one conclusion that can be drawn if one is to accept them both: space (distance) is an illusion of perception. It does not exist. The universe is ONE, as its name implies. Entangled photons are not the only experimental results that suggest a nonspatial reality. Quantum tunelling, in which particles appear to jump physical barriers at speeds greater than c, also seems to preclude the existence of space. Nonspatiality is an idea whose time has come. There is no hope that humanity can ever explore its own galaxy, let alone the universe beyond, if our travel speed is limited to that of light. Besides, even if we could travel at a fraction of the speed of light, any collision with a small pebble in space would be disastrous for the spaceship and its occupants. And I won't even get into the nasty problem of using rockets for breaking as the ship approaches its destination. The G forces would be immense. I predict that, in the not too distant future, we will have long-distance jump technologies that will allow us to move instantly from anywhere to anywhere. This can only happen when physicists decide to eliminate some of their ingrained assumptions about reality. Nasty Little Truth About Space: http://www.rebelscience.org/Crackpots/nasty.htm#Space
Edward, what you said souds very obvious. But as I understood it, entaglement is widely not seen like this. Did you read the article Bertlmann’s Socks and the Nature of Reality by John Stewart Bell? I didn t read it i must admit but everywhere is reffered to this article as far as this problem is concerned. In fact it says that the state of the photons is not defined by the entaglement but only by the mesurement. I also read that Murray Gell-Mann saw the whole problem like you do and was widely critizised by the community, by Anton Zeilinger, f.ex. too. If someone knows better (i m sure of that) - get it on!
it s called "Bertlmann s socks and the nature of reality"
For real information transfer, one should transfer information between villages in this experiment. Imagine that if in village A all incoming photons polarization could be arbitrary rotated to vertical or horizontal without even knowing what it was prior to rotation. In that case, their entangled pairs entering detector in village B should have opposite polarization. This way a message could be transferred from village A to village B. Positive outcome of experiment of this kind would be great.
Even if a man has technique or skill to climb on a tree he can't if he fails to tag spirit with this systematized kowledge. However if a man has spirit to do it, true he may not be that perfect or successful guy for all the time but there is probability of success at least once in thousands of such attempt. What is this that boosts him for atleast one success even in the want of that proper knowledge - we may like to call information arising out of lonely spirit, like that of detached particle or photon in the present case.
Hi, The speed of light is certainly not a constant. We are dealing with a situation simulate to the speed of sound where you must transverse a sound barrier. A light barrier which if you think about it can be transversed. Regards Dr. Terence Hale
Mathias - IMO, there is a reality to the waveform, with what state it will show being set at the time the photon is emitted. I must admit that I need to read (and probably reread a few times) the article that describes this test. Even so, it seems to me that how the photons will evolve is set until such time as they undergo an significant interaction which changes the state of one or the other. So how they will collapse is a given, but it is a given that we lack knowledge of until we collapse (or otherwise interact with) the waveform. The wierdness of QM comes from there being fundamental limits to what we can know. So with entagled photons, we can know that they will maintain the same state, and yet have no idea as to what that state will be at any given time.
The Special Theory of Relativity is flawed as is the General theory and obviously does not describe nature in its totality. Eventually it will have to be replaced by a more perfect understanding. The transfer of information at speeds faster than that of light could mean that causality is violated (and perhaps then time travel is possible) or it could also mean that the violation is only apparent and not real, and there is some other explanation to show how causality is not violated despite this being the case. There is at least one thing that "acts", "moves" or "propagates" faster than light and that is gravity, which acts at infinite speed over the length of the Universe.
I think that the FTL travel can be made in 30 years, if the LHC will discover indirectly that the string theory in wright, the spooky comunication is made on another dimension, and i belive that the warp drive tehnology will be reality.The Special Theory of Relativity it works only in ower dimensoins, just like the Newton law's.
It seems that even a simple logic can be sufficient to avoid playing in quantum mysteries and faster-than-light paradoxes. Photons are oscillatory/wave processes. What "entanglement" between two photons actually means is that the phase parameters of their respective undulation processes are put into correlation, by direct, local interaction and in full causality. And even when they are (carefully, coherently) separated after that (by any distance preserving coherence), the correlations will naturally persist. So when one finally measures the properties of those separated photons and finds those correlations there where they should be, why should it be so "mysterious" and involving any information transmission between separated photons? All the necessary informatiuon has already been transmitted between them during their interactive, local "entanglement" and naturally preserved after their separation due to their always maintained coherence. The most "unusual" part here is the growing technical ability to perform entanglement between and transmit single photons at ever larger distances without losing their coherence. It may be an impressive technology development, but without any mysteries, which are artificially added, it seems, as a "free supplement", in order to justify it as "fundamental science" rather than mere advanced technology. And there is also a subjective "love of mystery" clearly felt behind it and still dominating, unfortunately, in fundamental science development, after its artificial insertion during the "new physics" revolution of the 20th century. It was not there before: people used to believe in mysteries and do science separately, but starting from certain (not all!), unfortunately winning tendencies in the "new physics", we have until now the entanglement, here too, between totally subjective, artificial mystification and "objective", logically consistent kind of knowledge called science (see also my previous comment here). Science problems can be solved in a causal (though quite nontrivial!) way, but one should want this, rather than playing in supernatural mysteries and particularly esoteric "mathematical universes" as a fundamental basis of reality. Causality does not mean simplicity (it actually means complexity, see my references above!) and it even does not imply the absence of "supernatural" mysteries, but these ones should be situated at their true level, beyond the currently perceivable, "physical" reality (instead of being inserted into each elementary particle, within the official, "objective" science framework!). Can one hope that the great masters of knowledge will finally return to basic, elementary, human logic or will they continue to favour a perverted substitute for fading canonical religions under the label of "objective science" in all major temples of knowledge?
In addendum to my previous comment, Geoff says in the article: "For example, one could imagine that the photons might have shared information before they left Geneva — but Gisin’s measurements showed that they could not." Something is wrong here because any additional "measurement" would have spoiled the whole process. Besides, if "entanglement" is something real (and here apparently quite essential) what can it actually imply other than correlation establishment? We can hardly discuss all the relevant details here, but these considerations appear to be fundamental enough. And then, once again, what is it we're actually looking for, another confirmation of a supernatural mystery within every single photon or its causal solution? It's time to decide.
ron naldoda writes "Until people understand that light, like a plant in the ground, is effectly alive with pure knowledge, they will never unlock all the mysteries of the universe." Presumably he has understood this and has by this understanding unlocked the mysteries of the Universe. Andrei Kirilyuk seems to think that there is no "mystery" in the apparent transfer of information between two separate photons albeit "entangled". His "simple logic" doesn't wash. The property of entanglement can be discovered only by measurement as before that the polarisation of the photon is random and gets "fixed" only upon measurement. I agree with vlasie mircea that the discovery of additional dimensions, (at least one additional dimension as further dimensions would be out the scope of our present science to discover) would explain many mysteries and possibly enable us to discover and tap energy fields which are as hidden today as nuclear energy was when e=mc^2 was first revealed.
Ummm...doesn't the fact that they showed "it could instantly sense its twin’s behaviour without any direct communication" mean there WAS direct communication?? Be that - and comments like Uncle Al Schwartz's, that "Information existed only after opposite ends compared datasets - and that transmission happens no faster than lightspeed" - as they may, this is an incredibly exciting development. And I'll be willing to bet that the tenth coherent message to be transmitted instantaneously will start as follows: "Dear beloved; I am the widow of the late Galactic Coordinator, and I need you to access his frozen ebank account..."
Uncle AL the wavefunction collapsed down to an observable from a superposition of the two states, correct? then when you measure 1 the other must conform to opposite. this to me implies instantaneous information transfer. i think you might be a tad bit cynical in attempting to criticize the theory behind the experiment instead of the actual calculations made.