wave-particle duality of single photon, Full story at http://www.physorg.com/news88439430.html

http://www.physorg.com/news88439430.html

If I can believe it... this is fascinating. Good show!

Here is my interpretation of the duality as displayed in this experiment:

a) the single photon "pulse" clearly passes through all parts of the stensile, capturing the image;
but can only exchange energy in an "all or nothing" quantum, hence, a particle.

Is duality this simple?

Help me out here:

In the classic two-hole interference demonstration of duality, how far apart can the two holes be and yet still demonstrate self-interference of single photons?

Answer: many, many wavelengths.

This observed fact suggests that the energy "in the wave" is spacially dispersed until the instance of absorbtion of the photon in the detector, at which point the entire wavefront is destroyed, regardless of width!

In the classic experiment, the interference pattern appears as a distribution of hits from many photons. Many photons, but only one at a time.

Yet we see in this article that the wavefront can contain information spacially encoded???

I don"t believe it. In order to reconstruct the spacially encoded image, multiple photons must be destroyed. At a minimum, one photon for each pixel in the stensile. Correct?

So we"re not seeing the stensile image encoded in the wavefront of a single photon, but in the statistical distribution of many photons, over time.

The beam intensity is reduced to the level of a single photon at a time, but the whole image is not carried in the wavefront of any single photon. The information is encoded in the distribution of many photons.

Essentially this is little more than a 2 dimensional reconstruction of the conventional 1 dimensional "two slit" experiment.

What am I missing here?

A photon is a wave and not a particle. A wave can be broken up into ever smaller waves. Saying they only have one photon is like saying a tsunami is "just one wave." In the interference experiment, of course a wave can break up and interfere with other parts of itself.

Too easy interpretation of facts at least. And might be a reason og 100 years, or more, of blunder.

Saying particle is a wave is "contradictio in adiecto". Waves are from particles or in other words, those both are two poles of reality in front of our eyes.

Considering radiation (light) it seems the question is a connection between matter and space aspect of its nature.

Regards

REFRACTION: NEWTON WAS RIGHT

According to Newton's model of discontinuous (corpuscular) light structure, in the vicinity of water light particles receive more attraction than in air. Therefore, BEFORE the particles reach the surface of the water, their trajectory starts curving; the refraction is due to this curvature. According to the model of continuous light structure (electromagnetic field), AFTER entering the water waves move slower and this delay explains the refraction.

Clearly the curvature predicted by Newton makes the "continuous" explanation at least redundant: since the change in direction starts BEFORE the photons reaching the water surface, at the moment of penetration the refraction is already determined and subsequent events, including the change of the speed of light in water, are not very important.

Paradoxically, it is this change of the speed of light in water that definitively converted 19th century physicists to the "continuous" concept. Leon Foucault, 1850: "Ces resultats accusent une vitesse de la lumiere moindre dans l'eau que dans l'air, et confirment pleinement, selon les vues de M. Arago, les indications de la theorie des ondulations."

Einstein confirmed both the discontinuous nature of light and the curvature in the vicinity of bodies but never abandoned the model of continuous light structure which proved too profitable. Still at the end of his life he said: "I consider it quite possible that physics cannot be based on the field concept,i.e., on continuous structures. In that case, nothing remains of my entire castle in the air, gravitation theory included, [and of] the rest of modern physics."

Pentcho Valev
pvalev@yahoo.com

From a practical point of view, detecting even a few photons is a problem fraught by noise, random shot noise. Sometimes a null detection result is not unreasonable.

The picture looks to be made up of about 80 by 50 pixels .. unless they've found a way to detect partial photons this suggests there must be at least 4,000 photons involved. The lack of noise and the presence of a grey scale suggests several photons are involved at each pixel .. maybe (say) 10. We now have 40,000 photons. If their camera is (say) 5% efficient at detecting photons there must have been around a million photons involved .. or maybe just one.

Remarkable .. all the same.

-C2.

By AWT the photons are dense blobs of light wave, which are composing and decomposing by vacuum fluctuations repeatedly. They're result of interference of light wave with the periodic structure of space-time fabric, i.e. the Aether foam, which is forming the vacuum.



Therefore, every photon behaves like the spatial piece of the light wave and it can reconstruct the original image by the same way, like the piece of wave coming through slit in optical microscope can reconstruct the whole original image (albeit in poor quality).

This post has been edited by Zephir on Jan 20 2007, 04:08 PM

While it's true that photons can be thought of as waves, and these waves can interfere with each other (and themselves!), it is not accurate to say that the waves can be broken up into smaller waves. Photons are elementary particles and represent discrete quanta of electromagnetic energy. Even thought of as particles, they are not believed to have a substructure and consequently cannot be broken into more fundamental particles. The properties of a single photon's wave function are indivisible.

Our observations of the quantum nature of these photons do suggest that the photon can be in a superposition of many possible states (thus, in a manner of speaking, carrying much of the information present in the original stencil), but there is no known way of "figuring out" what all of those superpositions are. When you observe the photon, you only get a single observation and the superposition disappears.

As another poster mentioned, this allows the dual-slit experiment to work, because each observation can still be significant statistically, but that one photon does not allow you to reconstruct the original image.

Either the author of the article or the scientists decided to leave out the most important (revolutionary!) part of their research, the author misunderstood what the scientists are doing, or someone is being misleading in an attempt to make good press.

In fact it can be done easily just in the scope of the experiment described above. This is how the photon appears in the boson condensates - it appears as a single vortex, which moves through the condensate cloud by the observable speed.



It means, the photon energy is broken into collective motion of many thousand atoms in boson condensate. The trick is, the photon energy is not constant like at the case of fermions, but it depends on the light wavelength/frequency. By passing the light through boson condensate the speed of light decreases significantly, therefore the photon energy breaks into many particles and it can be divided by such way. After passing of boson condensate the energy of photon wave is restored from many low energy photons into collective motion of all the particles in boson condensate.

This post has been edited by Zephir on Jan 20 2007, 06:01 PM

So are you saying that when the energy (and presumably wave function) of this individual photon is distributed throughout the condensate, they can "extract" all of that in the form of lower-energy photons that can then be used to derive the original image?

While each photon "carries" some data, you certainly need more than a few
to reconstruct any sensible image at the detector. The posted article is somewhat
misleading in this sense -- while true that each photon interacted in a wave
fashion with the original mask, and that the wave function resulting from that
interaction is carried through the medium, that isn't quite the same thing as
a single photon carrying all of the information.

That isn't to say that this isn't useful. Slowing down the photons and having a
group of them carry a certain amount of information is still interesting.

These physicists don't know what information means. You can't retrieve the entire image from a single photon, therefore it is not encoded in a single photon. You need several photons that will eventually bin up the image statistically. A single photon can only carry a finite amount of information, that is determined by its wavelength.

But how it is possible for the photon where to "know" where to be detected, that is still quite a mystery. Probably best just to accept the CI.

Tricky.. if we assumed there was a totally black bit in the image then every photon would have to know not to go there .. by extension every photon would seem to 'know' about the entire image .. it just doesn't/can't represent it.

-C2.

Hi there,

Interesting article and interesting comments. Take a look at my site where i refer to this article. You might like it:

find it at: myglobalwebsites.com/WordPress/?p=679

From time to time you can find articles about these subjects. If you search for the word 'laser' you might find some blogs that you might like too.

Henri

I think what people seem to be missing is the beam-splitter. Perhaps the large number of photons travelling around the stencil i.e. down the other path after the beam splitter are interfere with the data carrying photons when recombined, providing both the information, and a sufficient number of photons to reconstruct the image?