From: jim bell <[email protected]>
To: Zenaan Harkness <[email protected]>; "[email protected]" <[email protected]> Sent: Saturday, August 6, 2016 12:06 AM Subject: Re: Quantum entangled-photon Chinese satellite: Article on Bell Inequality test experiments in Wikipedia article. https://en.wikipedia.org/wiki/Bell_test_experiments This article describes the various experiments over the years. I don't remember where i foundthe factor of 10,000 'c' velocity that the hypothetical interfering signal would have to travel atto interfere. Ooops! Found it at: http://newatlas.com/quantum-entanglement-speed-10000-faster-light/26587/ Quantum "spooky action at a distance" travels at least 10,000 times faster than light Brian Dodson March 10, 2013 The speed of entanglement dynamics is at least 10,000 times faster than light according to Prof. Juan Yin and colleaguesQuantum entanglement, one of the odder aspects of quantum theory, links the properties of particles even when they are separated by large distances. When a property of one of a pair of entangled particles is measured, the other "immediately" settles down into a state compatible with that measurement. So how fast is "immediately"? According to research by Prof. Juan Yin and colleagues at the University of Science and Technology of China in Shanghai, the lower limit to the speed associated with entanglement dynamics – or "spooky action at a distance" – is at least 10,000 times faster than light.Despite playing a vital role in the development of quantum theory, Einstein felt philosophically at odds with its description of how the universe works. His famous quote that "God does not play dice" hints at his level of discomfort with the role of probability in quantum theory. He believed there exists another level of reality in which all of physics would be deterministic, and that quantum mechanics would turn out to be a description that emerges from the workings of that level – rather like a traffic jam emerges from the independent motions of a large number of cars.[...] Prof Yin's experiment, which was a bit more complicated in detail than the above simplification, observed no difference in polarization direction. The time it would take light to travel between Alice and Bob was about 50 μs, while the action of the entanglement dynamics had to be less than 0.35 ns. The minimum speed of the entanglement influence is just the one divided by the other, or 144,500 times the speed of light. However, a number of factors go into the interpretation of the results, which reduce the lower limit of the speed of entanglement influence to about 10,000 times the speed of light. Notice that this result does not eliminate the possibility that the influence of entanglement actually is instantaneous – it merely sets a limit saying how close the influence must be to infinitely fast. Another possibility that is gaining credence is that entanglement dynamics may operate external to time, or at least may ignore time as it ignores distance. [end of portion quoted] Jim Bell From: jim bell <[email protected]> From: Zenaan Harkness <[email protected]> On Fri, Aug 05, 2016 at 09:10:42AM -0600, Mirimir wrote: ... > Here, from <http://www.scottaaronson.com/blog/?p=2464>: > > The violation of the Bell inequality has a schizophrenic status in > > physics. To many of the physicists I know, Nature’s violating the > > Bell inequality is so trivial and obvious that it’s barely even > > worth doing the experiment: if people had just understood and > > believed Bohr and Heisenberg back in 1925, there would’ve been no > > need for this whole tiresome discussion. >Seriously, I am none the wiser and cannot yet make sense of what they >are saying. >China apparently is putting this experiment in space - are they winning >a game on prediction of one particular bit with > 75% probability, and >if so, can they run that game numerous times to get that probability >close to 100%, and if so, can the random inputs to each side be made not >random so that the result of the game is transmission of information? >I cannot begin to answer any of these questions sorry... I will explain what I think they are doing in the fiber-optic version of the experiment,at least so nobody is permanently misled by my previous analogy. Imagine a central location on earth, let's call it Location B. 20,500 meters west of that is Location A, and 20,500 meters to the east of "B" is Location C. There's anoptical fiber going from "A" to "B", and another optical fiber going from "B" to "C".Two entangled photons are produced at Location B, then one is launched into fiber going to "A", and the other photon is launched from "B" into the fiber going to "C". After about 100 microseconds later (since the speed of light in that fiber is about 'c'/1.4584, where 1.4584 is the index of refraction of infrared in silica, thus 205.5 meters /microsecond), those photons emerge from their respective ends. Notnecessarily at the same time, because the length of the fibers may not be quiteidentical. They do the detection at Location A, and through prior arrangement theyschedule the detection at "C" a few nanoseconds later, possibly adjusting the physical length of the fiber to get the timing close to being correct.. Good synchronization could be achieved by GPS-controlled clocks, or perhaps a third fiber being used to synchronize local clocks at "A" and "C". They first detect at "A", and then detect at "C". And they might reverse the order, forcompleteness. But that's not the end:To determine that there has been more than a 50% correlation of the measured spins, they haveto transmit the type (angle) of measurement they make by ordinary optical fiber. (Although,it wouldn't have to be on an optical fiber: It could be a USB memory stick glued to theshell of a fast snail, I suppose. the important thing is that the information eventually getsto the other side, not how fast it takes to get there.) The information eventually gets to the other end, and they do the calculations andverify that SOMEHOW, the fact that a measurement at "A" somehow affected themeasurement at "C". If they "schmoo plot" (meaning carefully adjust, then plot on a graph) https://en.wikipedia.org/wiki/Shmoo , they can determine how fast some affecting particle or signal would have to travel to affect the receiver at the other end. Since the delay from Location "A" to "Location "C" would be (100+100) = 200 microseconds in a fiber, it would be 200/1.4584 = 137.136 microseconds from location A to location C,by air. (or in a vacuum, or by radio, etc.) That figure I found from an article a few years ago, that said it would have to travel at least 10,000x that of 'c' to affect the measurement, would require that the delay is measured by:137.136 microseconds/10,000 = 13.7126 nanoseconds. If the measurement at "A" occurred only 13.7136 nanoseconds before the measurement at "C", and yet there wasstill correlation, this shows that a velocity of at least 10,000 'c' to affect the outcome at "C". Therefore, I conclude that it would be easy to measure the minimum effective speed of the hypothetical interfering particle or wave. That particle or wave would have to travel 41,000meters in less than 13.7 nanoseconds, to achieve that interference. Time measurement to 1 nanosecond is easy, to 1 picosecond is doable, and in fact measurement of time valuesfar less than 1 picosecond can be accomplished. Jim Bell https://en.wikipedia.org/wiki/Bell_test_experiments
