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Einstein saves the quantum cat
Phys.Org ^ | 063-16-2015 | Provided by University of Vienna

Posted on 06/19/2015 7:37:01 AM PDT by Red Badger

Einstein's theory of time and space will celebrate its 100th anniversary this year. Even today it captures the imagination of scientists. In an international collaboration, researchers from the universities of Vienna, Harvard and Queensland have now discovered that this world-famous theory can explain yet another puzzling phenomenon: the transition from quantum behavior to our classical, everyday world. Their results are published in the journal Nature Physics.

In 1915 Albert Einstein formulated the theory of general relativity which fundamentally changed our understanding of gravity. He explained gravity as the manifestation of the curvature of space and time. Einstein's theory predicts that the flow of time is altered by mass. This effect, known as "gravitational time dilation", causes time to be slowed down near a massive object. It affects everything and everybody; in fact, people working on the ground floor will age slower than their colleagues a floor above, by about 10 nanoseconds in one year. This tiny effect has actually been confirmed in many experiments with very precise clocks. Now, a team of researchers from the University of Vienna, Harvard University and the University of Queensland have discovered that the slowing down of time can explain another perplexing phenomenon: the transition from quantum behavior to our classical, everyday world.

How gravity suppresses quantum behavior

Quantum theory, the other major discovery in physics in the early 20th century, predicts that the fundamental building blocks of nature show fascinating and mind-boggling behavior. Extrapolated to the scales of our everyday life quantum theory leads to situations such as the famous example of Schroedinger's cat: the cat is neither dead nor alive, but in a so-called quantum superposition of both. Yet such a behavior has only been confirmed experimentally with small particles and has never been observed with real-world cats. Therefore, scientists conclude that something must cause the suppression of quantum phenomena on larger, everyday scales. Typically this happens because of interaction with other surrounding particles.

The research team, headed by ?aslav Brukner from the University of Vienna and the Institute of Quantum Optics and Quantum Information, found that time dilation also plays a major role in the demise of quantum effects. They calculated that once the small building blocks form larger, composite objects - such as molecules and eventually larger structures like microbes or dust particles -, the time dilation on Earth can cause a suppression of their quantum behavior. The tiny building blocks jitter ever so slightly, even as they form larger objects. And this jitter is affected by time dilation: it is slowed down on the ground and speeds up at higher altitudes. The researchers have shown that this effect destroys the quantum superposition and, thus, forces larger objects to behave as we expect in everyday life.

Paving the way for the next generation of quantum experiments

"It is quite surprising that gravity can play any role in quantum mechanics", says Igor Pikovski, who is the lead author of the publication and is now working at the Harvard-Smithsonian Center for Astrophysics: "Gravity is usually studied on astronomical scales, but it seems that it also alters the quantum nature of the smallest particles on Earth". "It remains to be seen what the results imply on cosmological scales, where gravity can be much stronger", adds ?aslav Brukner. The results of Pikovski and his co-workers reveal how larger particles lose their quantum behavior due to their own composition, if one takes time dilation into account. This prediction should be observable in experiments in the near future, which could shed some light on the fascinating interplay between the two great theories of the 20th century, quantum theory and general relativity.

More information: Universal decoherence due to gravitational time dilation, Nature Physics (2015) DOI: 10.1038/nphys3366


TOPICS: Astronomy; Education; History; Science
KEYWORDS: physics; quantum; space; stringtheory; time
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To: Boogieman
“similar to a mass on a rubber mat attracting smaller masses that circle it”

The thing is, a depression on a rubber mat only causes that attraction because gravity already exists and is pulling the masses down. We can’t even imagine an example of how gravity works that doesn’t depend on a pre-existing notion of gravity!

Once again, xkcd for the win! :


21 posted on 06/19/2015 10:39:51 AM PDT by grey_whiskers (The opinions are solely those of the author and are subject to change without notice.)
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To: Tucker39
"...What relationship does this have, for instance, on the Space Station, where the people onboard are weightless; NO gravity? Why don’t we see some of this weird phenomina out there? Inquiring minds want to know.....where to acquire some of the stuff these guys are smoking, maybe?..."

I believe that the article indicates that by the time you are talking about molecular sized assemblies, that the OBJECT ITSELF is sufficient to suppress the quantum effects on its own.

That's why you could have something like an alcohol molecule floating in a region of essentially "gravity free" interstellar space, and that molecule won't "wink in and out" of existence like a single sub-atomic quark or something.
22 posted on 06/19/2015 10:46:34 AM PDT by Rebel_Ace (HITLER! There, Zero to Godwin in 5.2 seconds.)
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To: rstrahan
The problem I see with the “rubber mat” theory of gravity is that it is always demonstrated along a flat plane, i.e., the gravitational pull affects along the plane of gravity. Except gravity is not on a plane but a 360x360 area.

Don't you mean a 360 x 360 x 360 x time (the 4th dimension) area. . . and apparently quantum theory postulates eleven dimensions to properly account for everything.

23 posted on 06/19/2015 11:59:45 AM PDT by Swordmaker ( This tag line is a Microsoft insult free zone... but if the insults to Mac users continue...)
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To: Red Badger

Yeah? prove it!


24 posted on 06/19/2015 1:20:35 PM PDT by broken_arrow1 (I regret that I have but one life to give for my country - Nathan Hale "Patriot")
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To: broken_arrow1

25 posted on 06/19/2015 1:21:59 PM PDT by Red Badger (Man builds a ship in a bottle. God builds a universe in the palm of His hand.............)
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To: rstrahan

I think that’s the only way the human brain can process that space-time is a fabric, and not just open nothingness.


26 posted on 06/19/2015 1:50:25 PM PDT by rikkir (Anyone still believe the 8/08 Atlantic cover wasn't 100% accurate?)
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To: KC_Lion

You have put a smile on my face for the rest of the day!!


27 posted on 06/19/2015 1:53:05 PM PDT by rikkir (Anyone still believe the 8/08 Atlantic cover wasn't 100% accurate?)
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To: Red Badger; 6SJ7; AdmSmith; AFPhys; Arkinsaw; allmost; aristotleman; autumnraine; bajabaja; ...
Thanks Red Badger.


· List topics · post a topic · subscribe · Google ·

28 posted on 06/19/2015 3:22:47 PM PDT by SunkenCiv (What do we want? REGIME CHANGE! When do we want it? NOW)
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To: Tucker39

They’re actually in ‘free fall’, where the sinking rate of their ship approximates the curvature of the earth. It’s the same effect as in the Vomit Comet, or their airplane which goes into a parabolic dive allowing those inside to “feel” weightless. Yet, still being in the atmosphere, the plane must pull out of the dive in only a few minutes.

At the distance to the Space Station, and outside the earth’s atmosphere, the effect seems continuous. But even its orbit will eventually decay, necessitating its evacuation, or somehow propelling it into a new, higher orbit.


29 posted on 06/19/2015 4:43:22 PM PDT by onedoug
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To: Red Badger

And this jitter is affected by time dilation: it is slowed down on the ground and speeds up at higher altitudes. The researchers have shown that this effect destroys the quantum superposition and, thus, forces larger objects to behave as we expect in everyday life.

...

So if the boxed cat is far away from any gravitational field it can still be both alive and dead?


30 posted on 06/19/2015 4:50:24 PM PDT by Moonman62 (The US has become a government with a country, rather than a country with a government.)
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To: Red Badger

Okay, I will accept that as proof...


31 posted on 06/21/2015 9:05:12 AM PDT by broken_arrow1 (I regret that I have but one life to give for my country - Nathan Hale "Patriot")
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