(PhysOrg.com) -- One of the most well-known "rules" of quantum physics is that all quantum properties are lost due to environmental interaction. This rule, though, may not hold true in all situations. "We have discovered the first counter to this common rule," Sabrina Maniscalco tells *PhysOrg.com*. Maniscalco is a researcher at the Turku Centre for Quantum Physics, University of Turku in Finland. Along with fellow researcher (and husband) Jyrki Piilo, and Ph.D. student Laura Mazzola, Maniscalco has identified evidence that some quantum correlations can remain intact.

The results of their work are published in *Physical Review Letters*: “Sudden Transition between Classical and Quantum Decoherence.”

“Laura really did most of the work,” Maniscalco says. “She was studying different interactions between quantum properties and the environment, and looking for different correlations in noisy quantum systems. No one expected her to find strange behavior. When she first called Jyrki and me with the result, we thought it must be a mistake.”

Maniscalco and Piilo went over the data and realized that it wasn’t a mistake. “We checked the calculations again, and found that the time evolution of quantum correlations in this case remains constant for a long time. It represented a transition between classical and quantum decoherence, and the quantum property was not lost.”

This particular correlation can be found, for example, in quantum systems comprising of two qubits. “These qubits, each with different properties, such as different polarizations, have to interact with a type of noise that doesn’t change the energy of the qubits,” Maniscalco explains. “Instead of changing the energy, the noise just changes the phase, such as flipping polarizations. The type of noise that we have considered is one that contains all frequencies in a way that is very similar to white noise.”

While this discovery is theoretical, Maniscalco says that it has an experimental basis as well. “A very recent experiment has confirmed a type of quantum correlation that is not affected by the environment. And this is not a weird type of environment; it’s a natural environment that we could work in right now.” (For more on this experiment, see Jin-Shi Xu, et. al., “Experimental investigation of classical and quantum correlations under decoherence,” *Nature Communications* (April 2010). Doi:10.1038/ncomms1005.)

In the last 20 years, Maniscalco points out, technology has advanced to the point where it is possible to use single atoms or photons to build quantum logic gates for future quantum computers, or perform communication, measurement and cryptography tasks. “We’ve learned that it is possible to exploit the quantumness of the microscopic state, but in order for us to succeed, the quantum properties have to remain intact for a long time. That is a challenge, since once the properties are lost through interaction with the environment, a device can’t exploit quantumness.”

This discovery that certain quantum correlations are not lost in presence of the environment could lead an increased ability to exploit the quantum world for use in technological devices. Maniscalco points out that the idea that all quantum properties need not be lost through interaction with the environment presents more than interesting fundamental implications. “While this work has a surprising fundamental aspect,” she says, “it opens up a whole range of possibilities with applications in quantum technology, including computing, communications, metrology and cryptography.”

Next, Maniscalco says that her group, and Piilo’s group, at the University of Turku will need to study this effect. “We need to learn the most general conditions for this behavior, and see if it holds for other environments. We are also working toward deigning a quantum protocol that uses this state, so that we can demonstrate an application of this effect in practice.”

For more information, you can visit the Open Quantum Systems and Entanglement group and the Non-Markovian Processes and Complex Systems group web pages.

**Explore further:**
Quantum cryptography: No Signaling and quantum key distribution

**More information:**
Laura Mazzola, Jyrki Piilo, and Sabrina Maniscalco, “Sudden Transition between Classical and Quantum Decoherence, Physical Review Letters (May 2010). Available online: link.aps.org/doi/10.1103/PhysRevLett.104.200401

## otto1923

## Question

Quantum entanglement may be fiction but the link you posted is pure garbage. Certainly not worth a "click".

## CSharpner

They gave very little information in this article. I doubt it. But, if it /does/ it's not just "instantaneous" (which has no real meaning... basic relativity here), but would be communication to any two points in time between the time of creation of the entanglement and the time of the decoherence of the entanglement, which would even imply backwards in time transmission. Experimentation seems to always find a catch that prevents this. So, anything that would seem to allow this should immediately be suspect and definitely studied further.

And... what's up with a couple of you guys wanting to believe entanglement is fiction?

## Raygunner

## maxcypher

## Jarek

And the same in modern view on quantum mechanics: wavefunction collapse is a result of interaction with environment ('einselection') - there is unitary evolution behind - and so for 'Hamiltonian of the Universe'.

But we cannot fully trace these unitary evolutions - for us they 'loose their coherence':

-we don’t/can’t know precise parameters, like initial conditions,

-we cannot fully trace complicated motion (chaos),

-thermodynamically stable state usually have own dynamics, like atomic orbitals or quantum phases.

If we model such our lack of knowledge with proper statistical ensemble among possible scenarios - maximize uncertainty not locally like in Brownian motion, but globally-we get thermodynamical going to quantum mechanical ground state probability density ( http://arxiv.org/abs/0910.2724 )

## johanfprins

A matter wave's intensity is its mass-energy: It thus has a centre-of-mass. When it moves past an observer without morphing in shape and size the observer concludes it is "a particle".

As somebody asked J J Thomson: "How can you discover a particle which nobody has ever seen?"

## bluehigh

I observed a particle that wasn’t there

It wasn’t there again today

Oh, how I wish it would go away

(with apologies to W.H Mearns)

## tkjtkj

Femptosec's ?? eons??

and do let me know! thanks:

tkjtkj@gmail.com

## Jarek

Johan-in field theories like Klein-Gordon - with linear evolution operator, eigenfunctions are plane waves.

In this model particle's mass is literally 'smeared' through the whole universe and so it also 'smear' them into plane waves - but this way we cannot handle with multiple particles, so we try to construct them using such abstract eigenbase in quantum field theories, what leads to many problems.

We can handle with multiple particle also in simpler (and equivalent) way - by localizing them as solitons. It also automatically recreates e.g. quantum numbers as topological indexes, making them integer multiplicities. Such approaches is already uses to model mesons/baryons/nucleons ('mesonic field').

Models allowing for such solitons cannot longer be linear - their eigenbase/'waves' are no longer plane waves, but can be localized - gets corpuscular nature.

Wave nature is because of rotation of some intristic degree of freedom - like spinning/precession.

## Raygunner

## johanfprins

The Klein-Gordon and Dirac equations are both nonsense. A moving electron is a harmonic, coherent wave or else it will not diffract. This is an experimental fact. It is only under these conditions (When an electron IS MOVING) when de Broglie's relationship is valid. It is not valid for the "orbital electrons" around a nucleus; unless they have an energy larger than their rest mass.

Orbital electrons have energies less than their rest mass: Therefore they cannot have momentum (Einstein!) and therefore de Broglie's relationship is not applicable in this case.

An electron is a harmonic (light)-wave which can move with a speed less than light speed. It thus has an inertial reference frame within which it is a stationary wave having NO MOMENTUM. Its intensity within this reference frame MUST be its stationary energy; which is equal to its mass: All is consistent with classical mechanics. Please let us, for once and for all, trash the Copenhagen gobbledegook!!!

## johanfprins

Matter and light consist of fields formed from the same primordial energy: Free light can never be stationary, since its speed defines time and thus the size of our universe. We experience it as electro-magnetic energy.

In the case of a free electron, the wave can be stationary within an inertial refrence frame: So we experience its electromagnetic energy as mass-energy. Therefore a solitary electron has no electric-field "around" it. In fact the latter is impossible since an electric-field only forms between charges NOT around a solitary charge.

## Jarek

the most popular point of view of the modern physics - abstract: through the plane waves/Fourier transform works well in linear case.

But we know well that such waves can build extremely complicated spatial constructions like atomic nucleus - infinite waves fuzzy the picture.

Nonlinearities leading to such structures are considered through perturbative expansion - but it's extremely subtle construction, leading to many infinities and so we can work with only with qualitatively simple nonlinearities this way ... which should naturally explain the structure of particles, quantum numbers ... but in this approach they have to be introduced artificially.

I believe that to understand physics, we should focus on their classical spatial structure first - thanks of qualitatively proper nonlinearity - through constructions like topological solitons.

About orbiting electrons - so how do you think it qualitatively differs from two charged macroscopic (spinning?) balls orbiting in vacuum?

## johanfprins

Non-linearities + topolgies = infinities: Infinities is mathematios warning us that we are calculating nonsense: just as the quantum fielders have been doing for 80 years now.

Your question:

It differs totally since an electron around a nucleus cannot have any kinetic energy relative to the nucleus. It can only have kinetic energy if its mass energy is more than its rest mass energy. Thus the time-independent, stationary wave-intensity as approximately calculated from Schroedinger's equation IS the electron. The so-called spin is not a spin but the fact that the electron's mass-energy is determined by an electric- and a magnetic-field. In other words the electron is a "light-wave" which has inertia, while a pure light wave does not have inertia. A light wave gains inertia when it is absorbed by such a standing electron-wave.

## Jarek

No if you choose nonlinearity correctly - the 'trick' is to make energy minimum not in field's zero, like in Higg's mechanism - for example the field prefers energetically some direction, but in the center of singularity it has to loose it because of topology, what cost energy and gives particle the (rest) mass.

http://demonstrat...arities/

About electron - when particle's complete energy is smaller than it's rest mass??

And electron's spin denotes it's internal magnetic structure (Stern-Gerlach), while photon's spin denotes angular momentum it carries.

## johanfprins

All your arguments are based on accepting the validity of wave-particle duality, probability waves and complementarity. These concepts are only valid in Alexa's Wonderland. The Higg's mechanism is just a fairytale derived by using an undefined "order parameter" which can be chosen to fit what you want it to fit. Like the vector bosons the Higg's boson will probably be "found" in CERN, even though it does not exist. After having spent $20 billion they had better find it or have to admit that they are wasting the hard earned money of taxpayers.

Even you have to admit that this is a "trick"!!! How about arguing reality?

## johanfprins

Boundary conditions do not produce "artifacts" they determine the real physics. By ignoring boundary conditions or choosing them in such a manner that they have "no effect" one is not doing physics but VOODOO!. This is exactly what has gone wrong the last century. The fact that when making a measurement, the boundary conditions are changed has been ignored: It is so much simpler to postulate that a matter-wave is a probability distribution than to do the real physics by calculating how such a wave morphs when the boundary conditions change. It is so much simpler to dream up fictitious "order parameters" which can give one what one wants through "spontaneous symmetry breaking" than to really solve the wave-physics involved subject to the actual boundary conditions which actually determine what is really happening.

## Gene_H

## johanfprins

Yes I can! We know that our universe is not infinite in size and that the spectrum of black body radiation is determined by boundary conditions. Thus, the presence of micro-wave background radiation proves there are boundaries. For further information read the extract "New Horizons" of my forthcoming book which has been posted on my website two days ago.

## Gene_H

Your approach is similar to approach to people, who are saying, Universe is composed of free space-time (waves) only. And they're even right, because every particle is composed of space-time waves - so we can say, everything is composed of particles as well.

I'm rather orthogonal to these views because of their symmetry. Because we are smaller then the rest of Universe, the particle model is slightly more relevant.

## Gene_H

Symmetric particle-wave model would be relevant only under situation, we would form our Universe itself and nothing outside of our visibility scope would never exist. But because our visibility scope is apparently smaller then the Universe, we are forming "particles" with positive curvature in it and after then the particle character becomes more pronounced with increasing distance both into macroscopic scale, both into micro-scale up to certain limit.

Why we can expect, observable Universe is smaller, then the Universe as such? Because we shifted this boundary many times during human evolution. Before some time people believed, our Universe is formed by surface of Earth, later by solar system or Milky Way galaxy.

Now we are about to move this boundary again.

## Gene_H

## johanfprins

If spouting nonsense was a spot you would have been a leopard. So let us try again: As I have asked you many times before, let us start with a single argument and then work our way forwards by logic. So give me the answer to the following question: "Do you agree that the density of the frequency spectrum of black body radiation is determined by the size of the object (boundaries) within which this radiation has been formed?"

This is a simple question which does not require you to off in a tangent about "foam", "facial symmetry" and other nonsense which have nothing to do with the physics which is being discussed. Let us see if you are able to answer a simple physics question which even my grandchild can answer.

## Skeptic_Heretic

He/she/it is not capable of answering this question.

## Bloodoflamb

## Gene_H

"Which new testable prediction follows from your hypothesis?"

If you're able to derive even the existence of most perfect particles just by using of waves - what prohibit us in considering, everything is made of such particles?

## Gene_H

Which experiment should convince us, there exist some wave, which is definitely NOT formed by some particle field on background?

## Gene_H

http://www.mpg.de...dex.html

## johanfprins

Excellent question! The only thing that QED is famous for is "explaining" the Lamb Shift. This is because in this case there is a quantum-resonance caused by Heisenberg's relationship for energy and time. It is just by accident that this resonance is similar to "virtual photon exchange". The resonance-energy comes from the harmonic vibration of the wave which does not occur within three-dimensional space. This can easily be seen by plotting the time behaviour of the phase angle of a complex matter-wave (see my website "waves"). In this case the projections of the amplitude along external horizontal an vertical axes play a role. Harmonic movement is not within intensity of wave. When resonance occurs it comes from the kinetic energy outside three-dimensional space. The energy is part of the wave all along: Not of the "vacuum" as modelled by QED

## taka

The famous wave function collapse into particle when "observed" is also part of this religion. What actually happen was wave destruction when almost all of is energy was used to measure the "particle". With new more sensitive measurements it can be seen that some wave is left even after measurement. It didn't collapse, as it should according to quantum mechanical postulates. Meaning they are proved wrong.

## taka

## johanfprins

Yes taka, Jigga, what-have-you: You do not even understand high school physics. It is thus not surprising that you live with illusions. But please spare the rest of us with from your hallucinations: We are trying to understand physics without having to rely on illusions and hallucinations.