Addictive Science Posted December 31, 2013 Author Share Posted December 31, 2013 Any interaction which can alter, interact with, measure, or be altered by the state of the entangled particle. Suffice to say - again, but it bears repeating - you cannot transfer any information of any sort faster than the speed of light. There are no methods, tricks, subtle sleights of hand etc which allow this. Entanglement is complex, can be seen as non-local, is completely counter-intuitive, and could lead to great advances in science and technology; but it cannot and does not allow superluminal transmission of information. Thanks for the Info, Guess that puts this Idea to rest. No such luck other than a Laser/light/C wave transmission from a probe to Earth Receiver. Correct ? Link to comment Share on other sites More sharing options...
imatfaal Posted January 1, 2014 Share Posted January 1, 2014 ! Moderator Note popcorn sutton your post on quantum mind etc was split off to speculations - you must know by now that you may not introduce wild speculations into a thread on the main boards. Do not do so again. Do not respond to this moderation within the thread. Link to comment Share on other sites More sharing options...
Enthalpy Posted January 1, 2014 Share Posted January 1, 2014 You can measure the state of one, and that will force the other one into a single state. Slightly reformulated: If the particle at your detector was observed, then you know that the other particle was observable at the other detector. The polarization orientation etc of your detector doesn't change the statistics at the other detector. Link to comment Share on other sites More sharing options...
Addictive Science Posted January 1, 2014 Author Share Posted January 1, 2014 just wanted to check something, what happens when we close "the box"? do the entangled particles return to an undefined state? or are they useless as entangled particles now? if they are still usable could I open and close the box as many times as I wanted and get the same result with a definite spin that is the same as it were before? Link to comment Share on other sites More sharing options...
swansont Posted January 1, 2014 Share Posted January 1, 2014 Once you have put them in an eigenstate, you'll get the same result if you repeat the measurement. The particles are no longer entangled. Link to comment Share on other sites More sharing options...
Addictive Science Posted January 1, 2014 Author Share Posted January 1, 2014 Once you have put them in an eigenstate, you'll get the same result if you repeat the measurement. The particles are no longer entangled. Ok thanks Link to comment Share on other sites More sharing options...
hoola Posted January 4, 2014 Share Posted January 4, 2014 as to the question of no communications, even of entanglement failures being faster than light, doesn't newtonian gravitational laws require that the orbiting bodies "communicate" in a near instant fashion in order to maintain stable orbits? Link to comment Share on other sites More sharing options...
imatfaal Posted January 4, 2014 Share Posted January 4, 2014 as to the question of no communications, even of entanglement failures being faster than light, doesn't newtonian gravitational laws require that the orbiting bodies "communicate" in a near instant fashion in order to maintain stable orbits? Newtonian mechanics does have the idea of force at a distance - but you really do not need to go into why the equations work you just use them and Newton explicitly refused to go into the actual basis of them. If you try to say that Newtonian mechanics works and therefore there must be force at a distance you are putting the cart before the horse - Newtons work assumes force at a distance and therefore it cannot be used to prove this General relativity works on the notion of curved space time - it is far more complex but provides the same results in everyday situations (ie newtonian mechanics is the same as gr in limited situations), however GR also produces the correct results in more extreme situations; we have yet to find measurable problems with GR in the cosmological realm (although some might say dark matter and dark energy are problems). GR does not use force at a distance and predicts that gravitational changes will propagate at the speed of light. We have indirect evidence of this in the slowing down of binary pulsars which is the amount predicted by the theory of General Relativity through the expression of gravitational waves http://en.wikipedia.org/wiki/Hulse-Taylor_binary Link to comment Share on other sites More sharing options...
swansont Posted January 4, 2014 Share Posted January 4, 2014 Shorter: Newtonian gravity is known to be wrong on this, so it doesn't matter. 1 Link to comment Share on other sites More sharing options...
hoola Posted January 5, 2014 Share Posted January 5, 2014 (edited) ..so gravity is not a force per-se as it would require superluminal speeds, and some other mechanism is taking place giving the appearance of a force acting over long distances ? If the curvature of space idea supplants newton, doesn't that curvature information have to travel superluminaly? If so, then my question remains. Or do the actual newton equations not require faster than light action, regardless of the underlying mechanism at work.....?....here is a thought experiment.....if the sun were to de-materialize, we wouldn't know it for the 8 minutes it takes for the light to go out. But, wouldn't the gravity effect go to zero immediately, causing an instantaneous alteration of our orbit, seemingly a very noticeable change? Or would the gravity loss and light loss coincide? One last thing.... Inflation at the beginning of the universe is purported to have moved faster than C. So it does appear, if this is true, that there is no absolute prohibition against superluminality in the universe. Is this a one "special case" that allow faster than C movement to jibe theory with observations? Or did the early universe behave in a different manner, which it quickly evloved out of, ending the inflationary period, lowering the max speed allowable, then settling down toward the present day figure? Thanks, edd Edited January 5, 2014 by hoola Link to comment Share on other sites More sharing options...
swansont Posted January 5, 2014 Share Posted January 5, 2014 ..so gravity is not a force per-se as it would require superluminal speeds, and some other mechanism is taking place giving the appearance of a force acting over long distances ? If the curvature of space idea supplants newton, doesn't that curvature information have to travel superluminaly? No, the information travels at c. If so, then my question remains. Or do the actual newton equations not require faster than light action, regardless of the underlying mechanism at work.....?....here is a thought experiment.....if the sun were to de-materialize, we wouldn't know it for the 8 minutes it takes for the light to go out. But, wouldn't the gravity effect go to zero immediately, causing an instantaneous alteration of our orbit, seemingly a very noticeable change? Or would the gravity loss and light loss coincide? They would coincide. Changes in gravity propagate at c. Link to comment Share on other sites More sharing options...
hoola Posted January 5, 2014 Share Posted January 5, 2014 isn't the issue between the dynamics of gravity (waves) being held at C, while the static (straight-line) effects of gravity being above C, between non-orbiting bodies? Link to comment Share on other sites More sharing options...
Strange Posted January 5, 2014 Share Posted January 5, 2014 (edited) If they are static then surely there is no speed involved, c or otherwise? Edited January 5, 2014 by Strange Link to comment Share on other sites More sharing options...
swansont Posted January 5, 2014 Share Posted January 5, 2014 If they are static then surely there is no speed involved, c or otherwise? Indeed. I think of it as whatever is warping space has already warped it. That will be true as long as the source has been present for longer than d/c, where d is how far away you are. Link to comment Share on other sites More sharing options...
hoola Posted January 5, 2014 Share Posted January 5, 2014 I have heard the analogy of straight-line (static) gravity being a taut cord held between bodies with an instant transmission of forces, and dynamic gravity being ripples in the taut cord......I did see a problem with the analogy though, if the cord is so taut, no wiggles would be allowable.....so the only respected idea of faster than C velocity is the original inflation that occurred briefly at the big bang?...edd Link to comment Share on other sites More sharing options...
Addictive Science Posted January 15, 2014 Author Share Posted January 15, 2014 Just Came Across theses two articles and I'm having trouble seeing how they could or couldn't apply. http://phys.org/news/2013-08-quantum-outcome-unread.html#nRlv http://phys.org/news/2014-01-quantum-to-classical-transition-fuzziness.html Link to comment Share on other sites More sharing options...
imatfaal Posted January 15, 2014 Share Posted January 15, 2014 Just Came Across theses two articles and I'm having trouble seeing how they could or couldn't apply. http://phys.org/news/2013-08-quantum-outcome-unread.html#nRlv http://phys.org/news/2014-01-quantum-to-classical-transition-fuzziness.html The first article is along the line of what I was alluding to in post 12 - but more complicated. I believe it is to do with the fact that there are unitary transforms which act as operations at a quantum level which can act on an entangled state yet leave the two particles in a still entangled state - these are not measurements, they are quantum operators which change the state without any information leaving the system. The second concerns what actions cause a quantum state to appear/become classical - we have always said that interaction with the environment (ie measurement) will cause a quantum state to decohere into a classical state. This study build on the idea that it is not merely the interaction with the environment - but the nature / precision of that interaction that causes a quantum state to become classical. I cannot really say any more as it is beyond me. They change nothing regarding the fact that entanglement does not allow faster than light transmission of information. 1 Link to comment Share on other sites More sharing options...
Strange Posted January 15, 2014 Share Posted January 15, 2014 (edited) .I did see a problem with the analogy though, if the cord is so taut, no wiggles would be allowable..... What, you mean like a taut guitar string can't oscillate? so the only respected idea of faster than C velocity is the original inflation that occurred briefly at the big bang? Because expansion is defined as the rate at which distance increases between two points, it cannot be defined as a speed. If the universe is large enough, there are now, and there always have been, points sufficiently far apart that they are separating faster than the speed of light (whether or not inflation took place). Note that this has nothing to do with superluminal velocity; nothing moves locally faster than light. While special relativity constrains objects in the universe from moving faster than the speed of light with respect to each other, it places no theoretical constraint on changes to the scale of space itself. It is thus possible for two objects to be stationary or moving at speeds below that of light, and yet to become separated in space by more than the distance light could have travelled, which can suggest the objects travelled faster than light. For example there are stars which may be expanding away from us (or each other) faster than the speed of light, and this is true for any object that is more than approximately 4.5 gigaparsecs away from us. We can still see such objects because the universe in the past was expanding more slowly than it is today, so the ancient light being received from these objects is still able to reach us, though if the expansion continues unabated there will come a time that we will never see the light from such objects being produced today (on a so-called "space-like slice of spacetime") because space itself is expanding between Earth and the source faster than their light can reach us. http://en.wikipedia.org/wiki/Metric_expansion_of_space There is a whole other thread on this (probably several). Edited January 15, 2014 by Strange 1 Link to comment Share on other sites More sharing options...
Addictive Science Posted January 15, 2014 Author Share Posted January 15, 2014 The first article is along the line of what I was alluding to in post 12 - but more complicated. I believe it is to do with the fact that there are unitary transforms which act as operations at a quantum level which can act on an entangled state yet leave the two particles in a still entangled state - these are not measurements, they are quantum operators which change the state without any information leaving the system. The second concerns what actions cause a quantum state to appear/become classical - we have always said that interaction with the environment (ie measurement) will cause a quantum state to decohere into a classical state. This study build on the idea that it is not merely the interaction with the environment - but the nature / precision of that interaction that causes a quantum state to become classical. I cannot really say any more as it is beyond me. They change nothing regarding the fact that entanglement does not allow faster than light transmission of information. Thanks for that information. Link to comment Share on other sites More sharing options...
Addictive Science Posted February 9, 2014 Author Share Posted February 9, 2014 Just came across this new article. Has anyone read about this yet and do you know if it would apply to anything in this instance? Research team challenges the limits of famous quantum principlehttp://phys.org/news/2014-02-team-limits-famous-quantum-principle.html Link to comment Share on other sites More sharing options...
imatfaal Posted February 10, 2014 Share Posted February 10, 2014 Just came across this new article. Has anyone read about this yet and do you know if it would apply to anything in this instance? Research team challenges the limits of famous quantum principlehttp://phys.org/news/2014-02-team-limits-famous-quantum-principle.html From brief reading only; this research seems to confirm the hard and fast limits imposed by Heisenburg Uncertainty principle. The every present journalistic hype seems to say this challenges HUP - but it seems quite the opposite. It does not affect the prohibition of transference of information faster than light speed. Link to comment Share on other sites More sharing options...
Addictive Science Posted February 11, 2014 Author Share Posted February 11, 2014 From brief reading only; this research seems to confirm the hard and fast limits imposed by Heisenburg Uncertainty principle. The every present journalistic hype seems to say this challenges HUP - but it seems quite the opposite. It does not affect the prohibition of transference of information faster than light speed. Ok thanks, I'll look in to it some more. Link to comment Share on other sites More sharing options...
Implicate Order Posted February 11, 2014 Share Posted February 11, 2014 I tend to resolve the EPR paradox taking the following viewpoint of the non-locality of entanglement. Let's assume we have an entangled pair now seperated in space on either side of earth. Let's assume the entanglement refers to spin up or spin down properties. What is the actual reason that an observer cannot simultaneously measure which one is up or down without invoking spooky action at a distance? The actual reason is that the observer undertaking the measurement cannot be in two places at one time. Theoretically even a massless observer can only get to each location to conduct the measurement at a maximum speed of c. So an observer can only ever measure a spin up OR a spin down condition. Never a spin up AND and spin down condition simultaneously. The only way we can attempt to measure what is happening simultaneously is to introduce a second observer.....but how can you ensure both observers measurements can be perfectly synchronised. Relativity forbids it as confirmation of synchronisation can only be achieved at c. There will always be a delay that prevents confirmation of synchronised measurement. The issues associated with entanglement appear to me at least to be frame dependent problems. 1 Link to comment Share on other sites More sharing options...
hoola Posted February 11, 2014 Share Posted February 11, 2014 what about this "weak measurements" idea that I recently read about....in that a quantum state can be derived from an entangled particle without destroying the entanglement.....? I think I read it on Physics World a few months ago....And I am still curious of how inflation might have had a superluminal property, and if that is true, is it the one exception to the rule the universe now must abide? Link to comment Share on other sites More sharing options...
swansont Posted February 11, 2014 Share Posted February 11, 2014 The issues associated with entanglement appear to me at least to be frame dependent problems. The observers are in the same frame of reference. Link to comment Share on other sites More sharing options...
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