Quantum paradox directly observed -- a milestone in quantum mechanics
March 4, 2009
Quantum image
In quantum mechanics, a vanguard of physics where science often merges into philosophy, much of our understanding is based on conjecture and probabilities, but a group of researchers in Japan has moved one of the fundamental paradoxes in quantum mechanics into the lab for experimentation and observed some of the 'spooky action of quantum mechanics' directly.
Hardy's Paradox, the axiom that we cannot make inferences about past events that haven't been directly observed while also acknowledging that the very act of observation affects the reality we seek to unearth, poses a conundrum that quantum physicists have sought to overcome for decades. How do you observe quantum mechanics, atomic and sub-atomic systems that are so small-scale they cannot be described in classical terms, when the act of looking at them changes them permanently?
In a journal paper published in the New Journal of Physics, 'Direct observation of Hardy's paradox by joint weak measurement with an entangled photon pair', today, Wednesday, 4 March, authored by Kazuhiro Yokota, Takashi Yamamoto, Masato Koashi and Nobuyuki Imoto from the Graduate School of Engineering Science at Osaka University and the CREST Photonic Quantum Information Project in Kawaguchi City, the research group explains how they used a measurement technique that has an almost imperceptible impact on the experiment which allows the researchers to compile objectively provable results at sub-atomic scales.
The experiment, based on Lucien Hardy's thought experiment, which follows the paths of two photons using interferometers, instruments that can be used to interfere photons together, is believed to throw up contradictory results that do not conform to our classical understanding of reality. Although Hardy's Paradox is rarely refuted, it was only a thought experiment until recently.
Using an entangled pair of photons and an original but complicated method of weak measurement that does not interfere with the path of the photons, a significant step towards harnessing the reality of quantum mechanics has been taken by these researchers in Japan.
As the researchers write, "Unlike Hardy's original argument, our demonstration reveals the paradox by observation, rather than inference. We believe the demonstrated joint weak measurement is useful not only for exploiting fundamental quantum physics, but also for various applications such as quantum metrology and quantum information technology."
More information: Journal paper: http://www.iop.org/EJ/abstract/1367-2630/11/3/033011/
Source: Institute of Physics
Jan 23, 2007 |
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Shame on you, physorg, for publishing this!
Photon cancellation could perhaps be achieved but there are also two other problems with such approach, first photons are in reality formed by oscillations of electric and magnetic fields and for them to exactly cancel the phase of those oscillations has to be opposite for both photons in collision point. The phase depends on original phase and distance so you would have to know where the particle is to adjust distance so that both phases are opposite in location where the collision with the particle takes place.
Besides even if you managed to do it if the photons perfectly canceled out on the particle the particle would not interact with them at all, the photons would just past as through the vacuum and not detect the particle.
To locate something you have to send in a photon and this photon needs to bounce off (scatter) that object, you can then compute where this scattering took place by detecting the scattered photon and comparing it's direction with that of incident photon.
Unfortunately just as the photon is affected by bouncing off so is the particle, it will change it's speed and direction as a result so the information we get only informs us about past particle position or speed.
Forest for the trees and all that.
Photons are mis-labeled.
They are the reflection of the interactive energy point between forces (infinite amplitude fields from this dimensional egress viewing point-which devolve into interactive vortex at their junctive meeting point-thus frequency and oscillation of structure and their inherent stability and unwillingness to change-they are stressed into stability via the infinite 2-dimensional amplitude fields from the higher dimension), not a particle at all.
Turn the whole thing around - and it will make more sense.
Incidentally, this also explains why..that when the given military groups fired lasers (for distance and measurement calculations) at the given alien craft--that their propulsive fields would fail and the craft would crash.
Meaning..that laser light is merely a differential organization as reflective point off static field conditions that are different elsewhere-ie, outside of the 'light source'.
Einstein among eminent scientists suggested it arises because QM (esp. the Copenhagen interp.) was an incomplete theory. Besides suggesting that hidden variables are at work, he is famously quoted as suggesting he did not accept this "spooky action at a distance".
EPR is still widely debated and Hardy's Paradox is a nonsenscal maths game. The attributes of entanglement are more likely artifacts of the experiment caused by unknown (hidden) variables.
It was published for three weeks.
It was near immediately --pulled from publication.
Good luck finding it.