Quantum Entanglement Experiment Proves ‘Non-Locality’ For First Time, Will Permit Multi-Party Quantum Communication


Quantum entanglement — what Einstein called “spooky action at a distance” — involves a peculiarly strong correlation between two particles (typically, polarized photons) such that measuring a property of one particle simultaneously determines the property of the second particle — even when those two particles are separated by great distances (theoretically, even when the particles are at opposite ends of the universe). In quite recent years, quantum entanglement has even been observed for multi-particle systems.

However, despite these laboratory successes, Einstein’s critique of this entanglement phenomenon (which was never demonstrated during his lifetime) still manages to assert itself; such a correlation, or “communication”, asserted Einstein, could only occur at physically local distances (technically: local relativistic causality, where determining variables are in relative proximity to the measured particles). This causal necessity is called locality, or “local realism”, and is a consequence of Einstein’s “principle of local action”.

Analogously, a pool ball cannot influence another pool ball (analogous to the correlation between two photons) unless it at some point physically (locally) touches the second pool ball — even if through an intermediate source, such as another pool ball (where the kinetic energy is transferred through neighboring pool balls). This makes intuitive, “common” sense. The “spooky action at a distance” described in Quantum Mechanics — in which the behavior of one entangled particle seems to “know” or influence what the other entangled particles is doing — appears to violate this basic, common sense notion. This is one of the main reasons why Einstein initially rejected components of Quantum Theory.*

quantum entanglementIn Quantum Mechanics (QM), such two and multi-particle, entangled systems cannot be mathematically described independently of each other; they behave as a unitary system.

However, because previous entanglement experiments did not control for variables that might be enabling local causality, ”true” quantum entanglement (as proposed in the famous Bell’s theorem) could not be definitively demonstrated, or proven. The previous lack of experimental control creates a loophole, of sorts, in which Einstein’s principle of local action — that two distant objects can not have direct influence on each other — might still be valid (sometimes referred to as the ‘hidden local variables theory’).

Closing the Locality Loophole – Photonic Physics Fun With Alice, Bob, Charlie…and Randy

But quite recently, quantum physicists at the Institute for Quantum Computation (IQC) in Waterloo, Canada, were able to demonstrate 3-particle entanglement with non-locality for the first time.  The successful experiment may make possible multi-party communication and other advanced quantum information technologies.

For this newest real-world experiment, the IQC team conceived of a clever plan to exclude the possibility of some hidden variable(s) controlling the entangled state, thus closing the locality loophole. The team had to first generate photon triplets which exist in a quantum state known as a Greenberger-Horne-Zeilinger (GHZ) state (a state that involves three or more particles).

The choice to study photons in the GHZ state has a dual purpose. Paper co-author Professor Kevin Resch, Canada Research Chair in Optical Quantum Technologies, explains:

“Correlations measured from quantum systems can tell us a lot about nature at the most fundamental level. Three-particle entanglement is more complex than that of pairs. We can exploit the complex behaviour to rule out certain descriptions of nature or as a resource for new quantum technologies.” [source: see link, below]

Now, in the classic quantum thought experiment, the locations/recipients of the two entangled particles are traditionally given the proper names “Alice” and “Bob”, and any third party is named ”Charlie”. The team uses these classic designations to demark the key players in the entanglement experiment.

abcrUsing detectors set up, ironically, in several local spots — several trailers positioned several hundred meters from the IQC lab — the researchers at the lab (Alice) then beamed the entangled photons to these locations but with a time-delay in the transmission of the first photon. The other two photons were beamed (through two telescopes) to two other trailers (Bob, Charlie) separated from each other, and Alice, by approximately 700 meters. And, just to maintain a “space-like” separation between all three particles, they introduced a fourth party (“Randy”), located in a third trailer, that would act as a randomizing agent; Randy would randomly choose a correlation measurement for Alice (the lab team) to conduct on her photon (before it left the lab), without any local influence from either Bob or Charlie.  (above right) Photons generated in the lab were beamed to separate trailers in a field on the University of Waterloo campus.

Each detector at each trailer was integrated with a time-tagging device and a random number generator. The random number generators determined how the photon arriving at each detector would be measured, independently of any other measurements. The time-tagging devices made certain that each measurement transpired within an extremely short time frame (just three nanoseconds). This minute time window is deemed to be too quick for any possible communication or information transfer between particles to occur. This impossibility of local communication is crucial for proving quantum nonlocality (and, by way of Bell’s Theorem, nonrealism). rooftopFinally, by measuring the strength of the correlations between the three entangled photons (in the GHZ state), the team was able to verify entanglement and thus prove that quantum nonlocality is a real feature of the quantum domain. (right) Trailers parked more than 600m from the researchers lab on the University of Waterloo campus were used to separate three photons, proving the theory of quantum nonlocality.

Regarding the all-around success of the experiment, co-author and Professor Thomas Jennewein observes:

“The idea of entangling three photons has been around for a long time. It took the right people with the right knowledge to come together to make the experiment happen in the short time it did. IQC had the right mix at the right time.”

From High Tech Experiment to Practical Technology – What it All Means for Future Communications

By demonstrating a nonlocal correlation between three distributed and entangled particles, the team provided ‘proof of principle’ that communication beyond conventional “pairwise” communication is possible, and hopes that their results will lead to new “multipartite quantum communication protocols, including Quantum Key Distribution (QKD), third man cryptography and quantum secret sharing.”

Lead author Chris Erven from the University of Bristol elaborates on these possibilities:

“The interesting result is that we now have the ability to do more than paired quantum communication. QKD, so far, has been a pairwise system – meaning that it works best and with less assumptions when you’re only talking with one other person. This is the first experiment where you can now imagine a network of people connected in different ways using the correlations between three or more photons.”

The research team was comprised of students and faculty from the Institute for Quantum Computing and the Department of Physics and Astronomy in the Faculty of Science at the University of Waterloo. The experimental findings were published in Nature Photonics under the title ‘Experimental Three-Particle Quantum Nonlocality under Strict Locality Conditions’.

Some source material (including extended quotes and experiment photos) for this post came from the March 23, 2014 University of Waterloo News release: Experiment opens the door to multi-party quantum communication

* In an essay entitled “Quanten-Mechanik Und Wirklichkeit” (‘Quantum Mechanics and Reality’, 1948, Dialectica), Einstein wrote: “(…) The following idea characterises the relative independence of objects far apart in space, A and B: external influence on A has no direct influence on B; this is known as the Principle of Local Action, which is used consistently only in field theory. If this axiom were to be completely abolished, the idea of the existence of quasienclosed systems, and thereby the postulation of laws which can be checked empirically in the accepted sense, would become impossible. (…)”

And, long before Einstein, Sir Isaac Newton (1642–1727),  upon contemplating the idea of  action-at-a-distance, proclaimed it ”so great an Absurdity that I believe no Man who has in philosophical Matters a competent Faculty of thinking can ever fall into it”

Top Image:  (‘Streaming Fireworks – Fractal Design’) R.T. Wohlstadter via shutterstock.com

Diagram (second image from the top): Artistic rendering of the generation of an entangled pair of photons by spontaneous parametric down-conversion as a laser beam passes through a nonlinear crystal. Inspired by an image in Dance of the Photons by Anton Zeilinger. However, this depiction is from a different angle, to better show the “figure 8″ pattern typical of this process, clearly shows that the pump beam continues across the entire image, and better represents that the photons are entangled. Credit: J-Wiki at en.Wikipedia


Quantum Entanglement Experiment Proves ‘Non-Locality’ For First Time, Will Permit Multi-Party Quantum Communication was originally posted on: PlanetSave. To read more from Planetsave, join thousands of others and subscribe to our free RSS feed, follow us on Facebook (also free), follow us on Twitter, or just visit our homepage.

Apocalypse News Roundup: Corn Declines, A Killer New Virus, NASA Forecasts ‘Irreversible Collapse’ & Surviving The Zombie Apocalypse [VIDEO]


Greetings faithful readers…

Well, March is turning out to be a fine month for apocalyptica of seemingly every sort….So, as your faithful reporter of all things cataclysmic and eschatological (well, I try), I give you this friendly round-up of end-full news items for your reading pleasure, with brief commentary. To wit:

Maize Can’t Take the Blaze

We love our corn and corn products (chips, bread, cereal , syrup)…And so, a drastic decline in maize (the taxonomic name for corn) yields could trigger a drastic decline in this major sector of the consumer economy…But there’s plenty of corn in the world, right?

Well, the newest and slickest climate model indicates that certain key staple crops like wheat, soybeans, and especially maize, are very vulnerable to increases in temperature. The scientists developing the model sought to gauge “global scale, impacts of extreme heat stress on maize, spring wheat and soybean yields resulting from 72 climate change scenarios for the 21st century.” The simulation study (published last week in Environmental Research Letters) predicts a doubling of maize crop losses by the end of the century.  Wheat and soy also take significant losses, but recover for awhile in the northern latitudes (up to 2080) due to transient CO2 fertilization (note: the model was run under the RCP 8.5 scenario) .

This spells trouble for global food security, research on which by the UN FAO estimates food production must increase by 70% just to feed the world’s population by 2050.

Read more here: Heat Waves May Threaten Food Supply (there’s also a link to The Guardian story).

Contagion From the Cave:

Ok, so maybe mass food shortages just don’t’ do it for you (maybe “too long-term”)…Ok, how about some potential doom of the contagious variety?

Seems a new and pneumonia-inducing virion has been found in a cave somewhere in southwestern China (where it should have stayed). Apparently, the new virus — called Mojiang paramyxovirus (MojV), named after the Hunnan province of its origin –  resembles (genetically) a genus of viral pathogens known as henipaviruses (a combination of henta and nipah viruses), two of which are deadly to humans. But, intriguingly, it’s not being transmitted by the cave bats…but probably another troglodytic denizen.

Currently viewed as a “curiosity”, virologist Qi Jin, director of the State Key Laboratory for Molecular Virology and Genetic Engineering in Beijing, was cautious: “we have not established a direct relationship between human infection and MojV,” Jin is the lead researcher of the study,  reported in the June issue of Emerging Infectious Diseases.

Read the full Science Mag article A New killer Virus in China?  sn-virus

Photo (right): Courtesy of Qi Jin  (via Sciencemag.org) Chinese disease sleuths at work in the cave in Mojiang.

The Rise & Fall of Civilization…Apo-collapse Soon, Says NASA

Well, this certainly has gotten some decent Web coverage; nothing like doom-and-gloom from our usually grounded thinkers at NASA’s Goddard Space Flight Center. Some skeptical folks have suggested the direness of the prediction reflects the recent decline it the Space Agency’s budget, due to “austerity” and sequestration type stuff. But that’s just as likely to be ostrich-with-its-head-in-the-sand reactionism, as it is to be true. NASA, after all, got us to the moon and back; they are, in fact, rocket scientists.

Using a new multi-disciplinary computer model called ‘Human And Nature DYnamical’ (HANDY), the GSFC scientist take a look at the historical data showing that, far from being fringe speculation, ”the process of rise-and-collapse is actually a recurrent cycle found throughout history” and that “precipitous collapse – often lasting centuries – have been quite common.” According to the HANDY model’s findings, this holds true even for complex modern civilizations. The study was conducted by a team of natural and social scientists led by mathematician Safa Motesharri of the National Socio-Environmental Synthesis Center (supported by the NSF), and is to be published in the journal Ecological Economics.

To read more on the NASA-funded model predictions, check out this story in The GuardianNasa-funded study: industrial civilisation headed for ‘irreversible collapse’?

By the way, this is not the first time I’ve reported on a theory of ‘Collapse’, for further prognostications of global peril, check out my feature essay from 2011: The Science of Apocalypse: Climate ‘Flips’  and Global ‘Collapse’ – Two Dire Visions of the 21st Century.

Things to Wear During the Apocalypse When You’re (faced with the) UnDead…#1 – Wear ‘Death Cologne’

Zombies, according to urban rumor, are attracted to the smell of fresh flesh — the kind found on living humans — which presumably  keeps their revenant forms animated. Thus it would seem logical that the opposite of living flesh smell — a corpuscular one — would have a repellant effect on the walking dead.

Developed by chemist Rychelle Burkes, Ph. D, the noxious body sent is a combination of two well-named chemical compounds (types of polyamines): putrescine and cadaverine which are responsible for the repellant odor we give off when we die. According to Dr. Burkes, adding a dash of methanethiol (which smells like rotten eggs) give the cologne it’s final kick. It’s the only thing sure to ward off the undead. And where will these putrescent amines come from?  E. Coli bacteria, of course, the bacterial bugs commonly found in our colons will be put to work as microbial chemical factories. Ahh, yes, tiny, living beings serving a higher purpose…No word when the scent will hit a drug store near you.

 Read more: How to Survive The Zombie Apocalypse and/or watch this informative and comforting video:

Top Photo: Viktor Vasnetsov, the Four Horsemen of the Apocalypse, via Wikipedia






Apocalypse News Roundup: Corn Declines, A Killer New Virus, NASA Forecasts ‘Irreversible Collapse’ & Surviving The Zombie Apocalypse [VIDEO] was originally posted on: PlanetSave. To read more from Planetsave, join thousands of others and subscribe to our free RSS feed, follow us on Facebook (also free), follow us on Twitter, or just visit our homepage.

NASA Space Telescope Captures ‘Clearest Glimpse’ Of Our Milky Way Galaxy Ever Produced [VIDEO]



GLIMPSE360 – It was a decade in the making…over 2.5 million “snapshots” collected over a total of 172 observation days…it’s The Milky Way Galaxy like you’ve never seen it before, courtesy of the astronomical science teams at JPL and Cal Tech and the mighty imaging power (20 gigapixels) of the Spitzer Space Telescope.

The GLIMPSE (Galactic Legacy Mid Plane Survey Extraordinaire) 360 project is being described as the “clearest infra-red panorama of our galactic home” ever produced and the first time an “entire data set [of the galaxy] has been carefully stitched into a single image.”

Our Milky Way galaxy is essentially a flat disc (with a massive bulge in its middle) in the shape of a 4-armed spiral (with a dense “bar” of stellar masses running through its center region). Most all of the stars that we can observe from our Earthly view point are within 1000 light years from us. But our galaxy is over 100,000 light years across. This means that we can’t see (unaided) even a sizable percentage of stars in our galaxy.

But now, thanks to Spitzer, we are able to view the galactic disc “on edge”; the panorama covers just 3% of the sky but captures over 50% of the stars in our Milky Way — and 90% of its star-forming regions! This is due to the fact that most of the stars in our galaxy fall within a relatively narrow strip of space. This narrow strip is captured in this amazing interactive panorama which captures “everything” from the “brilliant core of the Milky Way to its outer edge.”

You read right: the new panorama is interactive — permitting anyone to zoom in and out on any section of the panorama at enormous scale differences. The website (http://spitzer.caltech.edu/glimpse360) provides a digital viewer to facilitate scalar viewing of the panorama.

The Spitzer panorama has utility beyond aiding current galactic analysis; it will serve as a preparatory “star map” to guide the planned James Webb Space Telescope (formerly known as the Next Generation Space Telescope, an international collaboration to be launched by 2018, or sooner) as it seeks out more detailed views of key star-forming regions.

For a quick galactic viewing, check out this awesome video of the GLIMPSE360 panorama (note: stars are colored blue {short wavelengths}, dust clouds/nebulae are colored red {long wavelengths}:

Top Image: (NASA) A false-color infrared image of the core of the Milky Way Galaxy taken by NASA’s Spitzer Space Telescope. Older cool stars are blue, dust features lit up by large hot stars are shown in a reddish hue, and the bright white spot in the middle marks the site of Sagittarius A*, the super-massive black hole at the center of the Galaxy.

NASA Space Telescope Captures ‘Clearest Glimpse’ Of Our Milky Way Galaxy Ever Produced [VIDEO] was originally posted on: PlanetSave. To read more from Planetsave, join thousands of others and subscribe to our free RSS feed, follow us on Facebook (also free), follow us on Twitter, or just visit our homepage.

Cosmologists Find ‘Tell-Tale’ Energy Pattern In The Cosmic Background, Confirming The Inflated Universe Theory

In the scientific discipline known as cosmology — the study of the origin and evolution of our universe — finding “hard” evidence in support of theory is often hard to come by; scientists must look for subtle indictors or traces of cosmological forces that act over vast regions of space, or, ones that may have [&hellip

Cosmologists Find ‘Tell-Tale’ Energy Pattern In The Cosmic Background, Confirming The Inflated Universe Theory was originally posted on: PlanetSave. To read more from Planetsave, join thousands of others and subscribe to our free RSS feed, follow us on Facebook (also free), follow us on Twitter, or just visit our homepage.