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Quantum process demonstrates superposition of ordered events

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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

#530370 — Quantum process demonstrates superposition of ordered events

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.


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#530422

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

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#530426

On Wednesday, November 4, 2015 at 2:50:13 PM UTC-8, nu...@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.

From which frame of reference?


--
Rich

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#530428

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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community, and physics-related social issues.

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