U of Toronto experiment named top breakthrough of 2011 by Physics World

Dec 16, 2011

Aephraim Steinberg and colleagues at the Centre for Quantum Information and Quantum Control at the University of Toronto had the top physics breakthrough of the year according to Physics World magazine.

Steinberg led an international team in applying a modern measurement technique to the historical two-slit interferometer experiment in which a shone through two slits results in an interference pattern on a screen behind. That famous experiment and the 1927 debates between Niels Bohr and , seemed to establish that you could not watch a particle go through one of two slits without destroying the interference effect: you had to choose which phenomenon to look for. Thus the quandary: how can we know reality if we cannot measure it without distorting it?

With their new experiment, Steinberg's group did what the physics textbooks said was impossible. They succeeded in experimentally reconstructing full trajectories which provide a description of how move through the two slits and form an . Their description of the experiment was published in Science and resulted in coverage by the world's science media, including a feature in Physics World.

"By applying a modern to the historic experiment, we were able to observe the average particle trajectories undergoing wave-like interference, which is the first observation of its kind. This result should contribute to the ongoing debate over the various interpretations of ," said Steinberg. "It shows that long-neglected questions about the different types of measurement possible in quantum mechanics can finally be addressed in the lab, and weak measurements such as the sort we used in this work may prove crucial in studying all sorts of new phenomena."

With regards to the being named top breakthrough of the year, Steinberg said, "When I was a graduate student, I told a mentor of mine that I was perplexed and fascinated by quantum mechanics and wished to spend my career studying it. He nodded and replied, 'That's all right in a young physicist – hopefully you'll grow out of it.' So what pleases me most about this honour is how much times have changed. Physics World is recognizing the study of the foundations of quantum mechanics as a respectable, even important endeavour. I hope that lifting taboos about what questions one can still ask will lead to continued discoveries about the implications of quantum mechanics and perhaps in the long term even new applications, as has been the case in the realm of processing."

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More information: http://physicsworld.com/cws/article/news/46193

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User comments : 19

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Callippo
1 / 5 (5) Dec 16, 2011
Actually the only actual breakthrough in physics, which occurred during the last year was public demonstration of cold fusion. This finding is indeed not welcomed with most of physicists, because it will marginalize their research in energy production, conversion and storage - not to say about fusion theorists, who still insist, it's impossible.

It's not surprising after then, my previous note about cold fusion has been deleted from here immediately: the physicists do appreciate only the findings, which are helping the close community of physicists and private lobby of companies, who are presenting their ads here - not the rest of human civilization.
AmritSorli
1 / 5 (2) Dec 17, 2011
Great discovery. What is to be add photon moves in quantum vacuum only (not in space-time) and time is a numerical sequence of its motion: http://www.physor...ion.html
Vendicar_Decarian
3 / 5 (2) Dec 17, 2011
"... demonstration of cold fusion." - Callippo

Showed it to be a scam.

And you still can't figure out why.

Sad
AmritSorli
1 / 5 (2) Dec 17, 2011
Photon has particle/wave nature without being observed in an experiment by the observer. Photon is a packet of energy that moves through the quantum vacuum. Moving in quantum vacuum creates waves of quantum vacuum. Like a boat moving in a sea.
In double slit experiment when we point photons only through one slit happens that waves of quantum vacuum caused by this photons move through the other slit and crate a well know interference pattern on the screen behind both slits.
Callippo
1 / 5 (2) Dec 17, 2011
Showed it to be a scam. And you still can't figure out why
LOL. Why?
Vendicar_Decarian
1 / 5 (1) Dec 17, 2011
"Moving in quantum vacuum creates waves of quantum vacuum." - Amrit

If that was the case, then energy would be lost as particles move from place to place and they would slow down as they move. In the case of light, it would red shift over distance.

Now we do see red shift in distant light, but it is interpreted as being do to recessional velocity.
Callippo
1 / 5 (2) Dec 17, 2011
If that was the case, then energy would be lost as particles move from place to place and they would slow down as they move. In the case of light, it would red shift over distance.
In normal fluid yes, but the vacuum is superfluid, the moving objects radiate only very subtle amount of energy in this way. The radiation of ripples actually requires an acceleration and this acceleration even must be larger than some limit. In general, objects don't radiate ripples at the water surface, when they're moving slower, than the average speed of particles, forming this surface. These bugs are using this feature of water surface ripples for echolocation and mutual communication - when they're moving in straight direction, they don't radiate ripples and they're invisible for predators. When they're moving in circles, they can exchange surface ripples.

http://www.physor...528.html
Callippo
1 / 5 (2) Dec 17, 2011
Therefore in quantum vacuum the energy of moving object isn't radiated, until it exceeds the energy of fundamental quantum state. The vacuum wave around object in motion is localized and it doesn't spread into distance. They're rather similar to the wake wave formed above submarine of fish floating beneath the water surface.

http://www.aether...tum3.jpg

This doesn't apply for charged objects, which do radiate energy with interactions of microwave noise of vacuum even at the speed close to the speed of light. The electrons within superconductors are moving in very high speed, so they're supposed to drag space-time a bit.
Seeker2
not rated yet Dec 18, 2011
waves of quantum vacuum caused by this photons move through the other slit and crate a well know interference pattern on the screen behind both slits.
I'm trying to figure do these waves also move at the speed of light?
Callippo
1 / 5 (2) Dec 18, 2011
I'm trying to figure do these waves also move at the speed of light?
Of course, or they couldn't determine the path of particle in advance.
Seeker2
not rated yet Dec 22, 2011
I'm trying to figure do these waves also move at the speed of light?
Of course, or they couldn't determine the path of particle in advance.
So the waves get there first and guide the particles along their path.
rawa1
1 / 5 (1) Dec 22, 2011
Of course: the vacuum foam is behaving like the undulating soap foam and it becomes more dense at the places, where it's shaking (undulation) occurs in most intensive way. Therefore the flabelliform patterns formed during constructive interference of deBroglie wave of moving particles are behaving like the waveguides and they affect the probability of the further motion of particle (which is itself behaving like travelling soliton wave, so it follows the path of highest vacuum density along direction of constructive interference).

http://www.physor...511.html

The same mechanism has been demonstrated at the vibrating surface of water, onto which the tiny oily droplets jumped. The vibration of water surface expanded this surface just at the places, where the constructive interference occurred, so that the droplets used it preferentially. It's exact analogy of the quantum double slit experiments, just in 2D dimensions.
Seeker2
not rated yet Dec 26, 2011
I'm trying to figure do these waves also move at the speed of light?
Of course, or they couldn't determine the path of particle in advance.
So the waves get there first and guide the particles along their path.
Actually the particle is a wave of energy. If it finds two paths to follow the energy is split between the two paths. Each slit now becomes a source of energy with the same phase and wavelenth. Where the two new waves intersect causes a diffraction pattern because of the path difference between the two new emitters at the two slits. Of course if the path lengths are the same you get the central bright region.
Seeker2
not rated yet Dec 26, 2011
So the waves get there first and guide the particles along their path.
Actually there's a point here, strange as it may seem. If the wavefront moving along with the particle meets an obstruction it says oops and checks the next nearest point on the wavefront. When it finds an opening it says ok energy follow me. If it finds two openings of course they have to share the energy.
Seeker2
not rated yet Dec 27, 2011
If it finds two openings of course they have to share the energy.
Well maybe we should look at it this way: The energy is spread out evenly throughout the entire(spherical) wavefront. The proportion of the energy passed through each slit is proportional to the area projected onto the wavefront by the slit to the total spherical area of the wavefront.
Seeker2
not rated yet Jan 08, 2012
Photon has particle/wave nature without being observed in an experiment by the observer. Photon is a packet of energy that moves through the quantum vacuum. Moving in quantum vacuum creates waves of quantum vacuum. Like a boat moving in a sea.
The photon is the wave of electromagnetic energy propagated in spacetime. No boat. The wave is propagated, that means it gets a free pass through spacetime. No energy is expended. You might say as far as light waves are concerned spacetime is frictionless.
Vendicar_Decarian
1 / 5 (1) Jan 08, 2012
Incorrect. The average speed of a water molecule is several hundred miles per hour. Boats clearly need not travel at that speed in order to generate a ripple.

"In general, objects don't radiate ripples at the water surface, when they're moving slower, than the average speed of particles, forming this surface." - Callippo
Vendicar_Decarian
1 / 5 (1) Jan 08, 2012
Pure supposition on your part.

"In normal fluid yes, but the vacuum is superfluid, the moving objects radiate only very subtle amount of energy in this way. " - Callippo

Waves on the surface of superfluid helium can be seen here.

http://www.youtub...FPpuK-Jo
Callippo
not rated yet Jan 08, 2012

Waves on the surface of superfluid helium can be seen here.
The video just demonstrates, when the helium changes into a superfluid, it becomes suddenly still. It's because inside of boson condensate the energy is quantized. To induce the wave in superfluid the energy density must be higher than the energy of its fundamental quantum state.

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