• by HackOfAllTrades on 10/13/2020, 5:02:44 AM

    Dr. W. M. Stuckey shows that the origin of quantum entanglement is none other than Einstein's own Principle of Relativity (No Preferred Frame of Reference).

    Einstein's famous 1905 paper on Relativity applied this principle to Translational Frames, showing it requires the Universal constant c (speed of light) to be the same in all such frames. Were it not, the frame in which c was highest would be the only frame at rest.

    But the same principle must require there to be no Preferred Orientation. This leads to the requirement that Planck's constant h be the same in all frames. If the Stern-Gerlach experiment could give results between +h and -h, then the orientation producing the maximum value would be a preferred frame.

    And because of that, when Alice and Bob measure entangled quantum particles, their combined results must violate Bell's inequality.

    But to my mind, the biggest take-away is that Einstein's Principle of Relativity absolutely requires that conservation can only be on average.

    All right, that's a ridiculously condensed summary. Enough to make your head spin :-)

    The title paper is for general audiences, and references the original paper at https://www.nature.com/articles/s41598-020-72817-7.pdf

  • by andomar on 10/13/2020, 7:45:59 AM

    Say you put a red marble and a blue marble in two envelopes. You randomly post one envelope to Australia. One year later, you open the other envelope. You now know the color of the marble in Australia.

    What's the difference between this and quantum entanglement?

  • by mellosouls on 10/13/2020, 7:20:31 PM

    I'm a little sceptical of these authoritative-sounding "overviews" that are essentially plugs for the author's thesis - the paper providing the justification for the title quietly inserted in this case right at the end of the article.

    Personally, I'd prefer third party summaries of the thesis when it has been established as an interesting contribution, and the original article to stick to what is actually accepted by the mainstream; or at the very least to be more up-front that this is actually based on a new paper by the author.

    That's not to say this paper is wrong - I'm not remotely qualified to judge (and it happens regularly in articles plugged on HN); I just find the way these things are presented as a bit iffy.

  • by qq12as on 10/13/2020, 10:48:19 AM

    Does someone have a good explanation/intuition for why you cannot exploit quantum entanglement to send information faster than light?

    If me observing the particle in Australia alters the probability distribution of your particle in USA, can't I only observe the particle when I want to communicate 1 and never observe it when I want to communicate 0?

    Edit: thanks a lot for the answers! I guess it boils down to the fact that the Australian guy cannot condition his decision on the (unknown) spin of his particle -- if he could (eg: had access to the local hidden information) then he would be able to update the USA's probability distribution instantaneously and use it to communicate

  • by rssoconnor on 10/13/2020, 3:34:04 PM

    By this analogy, (non-local) hidden variable theories are the ether of quantum mechanics: The ether determines the true value of simultaneity, and hidden variables determine the true outcomes of measurements.

    For both theories the physics surrounding them just happens to make their presence undetectable. In the case of the ether, the ether wind just happens to shrink the arms of the Michelson-Morley interferometer by exactly the amount needed to prevent the interference pattern from detecting the ether wind. In the case of hidden variable theories, the predicted joint probability distributions just happen to make the hidden variable values themselves uninferable.

  • by thyrsus on 10/13/2020, 8:12:19 PM

    Please correct errors in the following: polarization of photons is another form of entanglement, and I seem to recall there are others. Does this result solve the "action at a distance" problem for all of them?

  • by unkown on 10/13/2020, 7:49:46 AM

    so this means the quantum computing is not possible ?