Extending Einstein's spooky action for use in quantum networks

Extending Einstein's spooky action for use in quantum networks

An international team, including researchers from Swinburne University of Technology, has demonstrated that the 1935 Einstein-Podolsky-Rosen (EPR) quantum mechanics paradox may be extended to more than two optical systems, paving the way for exploration of larger quantum networks.

Quantum mechanics is the theory used to describe nature's smallest systems, like atoms or photons.

The EPR paradox pointed out that two well-separated systems can have a strange type of quantum connection, so that what happens in one system seems to immediately affect the other.

This connection has recently been called 'EPR steering entanglement'.

EPR steering is the nonlocality – what Albert Einstein called 'spooky actions at a distance' – associated with the EPR paradox and has traditionally been investigated between only two parties.

An experiment performed by researchers from the Australian National University (ANU) and Tianjin University supports the predictions of theoretical work developed by researchers at Swinburne and Peking University.

"We used an optical network to experimentally confirm how this spooky type of entanglement can be shared over not just two, but three or more distinct ," Dr Seiji Armstrong, from the Quantum Computing Centre Node at ANU, said.

Previously, this sort of entanglement had been studied for only two systems. 

"The strength of the entanglement created in our network allows us to confirm rigorously – without using any additional assumptions that would create scientific loopholes – the genuine tripartite of three of the optical fields. The experiment therefore provides an important step towards validation of mesoscopic ," Swinburne's Professor Margaret Reid said.

ANU's Professor Ping Koy Lam said the experiment also identified properties that may be useful in establishing secure quantum communication networks where shared sequences of numbers created between two parties need to be kept secret from a third party.

The important new feature is that the correlation is established with minimal assumptions about the nature of the equipment used to measure all but one of the fields.

Dr Qiongyi He from Peking University said that this helps in devising strategies, called device-independent cryptography, to outsmart hackers that have may have compromised equipment, such as computers or iPhones.


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Einstein's 'spooky' theory may lead to ultra-secure internet

More information: "Multipartite Einstein–Podolsky–Rosen steering and genuine tripartite entanglement with optical networks." Nature Physics (2015) DOI: 10.1038/nphys3202
Journal information: Nature Physics

Citation: Extending Einstein's spooky action for use in quantum networks (2015, January 15) retrieved 23 August 2019 from https://phys.org/news/2015-01-einstein-spooky-action-quantum-networks.html
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Jan 15, 2015
Quantum Mechanics has to do with the motions of particles at the subatomic levels. Since light is at this level it isn't surprising though heartening that Einstein's calculations appear again to be correct.

Though a lot of these lower level physics experiments seem to be continually getting in the way of the more far out theories.

Jan 15, 2015
This is why Seth Shostak's listening equipment isn't picking up any signals. Those who have survived their "Great Filter" are using this in its most advanced form.....

Jan 15, 2015
Thank goodness there's not the usual tripe about faster than light communications by entanglement. Refreshing not to see nonsense here. This is a good opportunity for increasing network security from external taps.

Jan 15, 2015
Would be interesting to employ quantum discord, which is much more robust than delicate quantum entanglement. Discord is prevalent in rock music and unites quantum brains into more coherent states without cooling everyone to near absolute zero

Jan 15, 2015
Would be interesting to employ quantum discord, which is much more robust than delicate quantum entanglement. Discord is prevalent in rock music and unites quantum brains into more coherent states without cooling everyone to near absolute zero

Chev - it's in the beat...

Jan 16, 2015
The Keshe Plasma Reactor design has a similar concept. Good work ya'll.

It's great when we can confirm each others' work and add to it.

Jan 16, 2015
Y'know... I think I asked if entanglement measurements of more than 2 quantums had been done, in another thread a few months ago...
Glad to see they took my suggestion...:-)

Jan 16, 2015
named after something Einstein never really accepted as reality

Jan 16, 2015
Quantum communication will be EXACTLY about faster than light. FTL does not have to right away mean real time control of satellites in orbit of, say, Jupiter. It can mean faster computers when used on a much smaller distance scale, like the die of a microprocessor. That would make processor speeds unlimited except by path interruptions to further process, etc. Moore's Law getting yet another lease on life. This quality is NOT gonna be overlooked by corporations out to make a buck, so naysayers, pathoskeptiks, and luddites and other trouble makers had better watch out cuz' the money this time is gonna kick you to the curb faster than you can say 'relativity'!

Jan 22, 2015
Someone help me out here: Is Quantum Mechanics a literal description of (theoretical) reality at the quantum level, or is it just a mathematical model that allows us to predict the behavior of particle-waves? In other words: is Schrodinger's cat particle REALLY both dead and alive simultaneously before we open the box, or are we only treating it as both dead and alive in our mathematical model in order to account for the unpredictability in the system? When we open the box, are we really forcing the universe to decide if the cat particle is dead or alive? Or are we simply adding a new known value to the model?

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