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Re: Quantum process demonstrates superposition of ordered events

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On 11/4/15 4:50 PM, nuny@bid.nes wrote:
> On Wednesday, November 4, 2015 at 11:04:06 AM UTC-8, Sam Wormley wrote:
>> Quantum process demonstrates superposition of ordered events
>>> http://phys.org/news/2015-11-quantum-superposition-events.html
>>
>>> (Phys.org)--In a quantum superposition, a quantum object can be in two
>>> incompatible states at the same time, which is famously illustrated
>>> by Schrödinger's dead-and-alive cat. Recent research has shown that
>>> it's possible to have a superposition not only of incompatible
>>> states, but also of incompatible orders of events. We often think of
>>> events occurring in a definite chronological order, with event A
>>> happening (and causing) event B, or vice versa. But in certain
>>> quantum processes, events don't happen in a single definite order,
>>> but instead both orders (A before B, and B before A) occur at the
>>> same time. This counterintuitive superposition-like phenomenon is
>>> called "causal nonseparability."
>>>
>>> "In everyday life, we are used to experiencing one thing always
>>> happening after another, effects following their causes," Mateus
>>> Araújo at the University of Vienna and the Institute for Quantum
>>> Optics and Quantum Information in Vienna, Austria, told Phys.org. "So
>>> it is a bit unsettling to realize that deep down Nature doesn't work
>>> like this, that things can happen without a definite causal order,
>>> where we cannot say what is the cause and what is the effect."
>>>
>>> Until now, causal nonseparability in quantum mechanics has been
>>> conceived only in a very abstract way, with no clear physical
>>> interpretation. But in a new paper published in the New Journal of
>>> Physics, Araújo and coauthors have described an example of a physical
>>> quantum process that demonstrates causal nonseparability.
>
>    A version of this has already been seen in "macroscopic" objects being put into a superposition of states:
>
> http://arxiv.org/pdf/0807.1834.pdf
>
>    The events that cause either oscillation, or no oscillation, are mutually exclusive.
>
>    For the cantilevered mirror to be in a superposition of oscillating and not oscillating, both sets of causal events have to have happened at the same time.
>
>
>    Mark L. Fergerson
>


   Thanks, Mark.



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Quantum process demonstrates superposition of ordered events Sam Wormley <swormley1@gmail.com> - 2015-11-04 13:04 -0600
  Re: Quantum process demonstrates superposition of ordered events "nuny@bid.nes" <Alien8752@gmail.com> - 2015-11-04 14:50 -0800
    Re: Quantum process demonstrates superposition of ordered events RichD <r_delaney2001@yahoo.com> - 2015-11-04 15:07 -0800
    Re: Quantum process demonstrates superposition of ordered events Sam Wormley <swormley1@gmail.com> - 2015-11-04 17:08 -0600

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