Proving an aspect of the AB effect: when Newton's Third Law doesn't work
December 4th, 2007 By Miranda Marquit
University of Nebraska-Lincoln graduate student Adam Caprez fires up the pulsed electron laser used to test the no forces aspect of the Aharonov-Bohm effect. Credit: Herman Batelaan
An action doesn’t always result in a reaction.
One of the interesting phenomena present in quantum mechanics is the Aharonov-Bohm (AB) effect. The AB effect predicts that a charged particle, usually an electron in experiments, shows effects from electromagnetic fields in regions where the particle is excluded. This leads to the interesting fact that, in electromagnetism, Newton’s Third Law of Motion doesn’t always hold true.
Herman Batelaan explains to PhysOrg.com: “If you want to move anything in the world around you, you need forces. But in the Aharonov-Bohm effect, the electron reacts without any forces. There is no force, but something happens.”
Batelaan, a scientist at the University of Nebraska-Lincoln oversaw an experiment done by graduate student, Adam Caprez, and Brett Barwick to demonstrate the absence of forces in the AB effect. A description of the experiment, and their results, is available in Physical Review Letters: “Macroscopic Test of the Aharonov-Bohm Effect.”
“The interesting thing,” Batelaan says, “is that experimentally scientists have detected evidence of this effect, and it is mentioned in textbooks. But nobody had shown that no forces are there.” The experiment performed at the University of Nebraska-Lincoln constitutes the first demonstration of a lack of forces. “We know the effects, and this is expected.” Batelaan continues. “Theoretically, scientist predicted this, but we want to see this. Now we have it.”
Experimental demonstrations of the AB effect usually include carefully controlled electrons using a distant electromagnetic field. “We understand the physics of this, such that we can take electrons and control them so well that we can see quantum mechanics happening,” Batelaan says. In order to perform the current experiment, the team used a pulse laser to hit a metal needle, a method developed at Stanford.
“You have a pulsed electron source,” Batelaan explains, “and you have something you can time.” Batelaan says that if a force is present there will either be a delay, or an early arrival. The experiment showed no time delay, and this demonstrates that the AB effect lacks forces, even though something is clearly happening with the electrons.
Caprez said that what he found most appealing is that, “we have a rare example where quantum mechanics, electromagnetism and relativity are all working at the same time.”
As far as immediate applications are concerned, Batelaan admits that there isn’t much about this experiment that will be useful on a practical level right now. But, he insists, “This is very fundamental quantum mechanically. It is helpful in terms of a better understanding on the quantum level.” He points out that devices are reducing in size at a rapid pace, and that as science and technology shrink, “we will need to understand the interplay between quantum mechanics and electromagnetic fields as deep as possible.”
Copyright 2007 PhysOrg.com.
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Jun 29, 2009 |
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Newton's 3rd says that momentum is conserved. The "effect" is a phase shift, not a change in momentum. So, if the electron did feel a force, that would be a violation of Newton's law. He showed that there is no violation, the opposite of what the article says.
This author needs to go work for NewScientist. They'd appreciate her skills there:P. Misleading title, misleading article, and borderline wrong "facts". Yup, definitely NS material.
This is not consistent with linear causality either in the Newtonian or Relativity sense. The continuous field concept in the sense of matter embedded in a preconceived a priori space-time is faulty. Einstein himself wrote: I consider it quite possible that physics cannot be based on the field concept, that is, on continuous structures. Then nothing remains of my entire castle in the sky, including the theory of gravitation, but also nothing of the rest of modern physics. (In a letter to Michele Besso in 1954, the year before he died.) In a discontinuous universe a different picture emerges that is consistent with the evidence and with common sense.
Planck's constant indicates a discontinuity in the synchronous projection of particulate matter as in a cosmic movie. The electromagnetic rainbow is sliced across it entire breadth with the recurrent projection of each frame. EM radiation comes to us as a discontinuous series of pulses. The universal component of independently projected atoms regulates their synchronous projection in a series of independent still space frames linked up by light. All relative motion is a series of quantum jumps between these discrete still particle frames. Light is the only activity within each space frame and it is quantized by each space frame, along with space and time. Light comes from inside atoms and has a universal relationship to each atom, accounting for its universal velocity. So light itself defines space. Where there is no light, there is a black hole in space. And obviously physical effects can not be transmitted through the integrated fabric of space-time faster than light if it defines space.
This requires that Newtons Third Law does not apply in a continuous way to quantum events measured over short periods of time, because there is a primary interval of time associated with the synchronous projection of each atomic space frame. Successive space frames are discontinuously assimilated from an integrated timeless quantum frame (called the Void) by the universal characteristic of matter. The Void is a spatially indeterminate energy field orthogonal to the integrated fabric of space-time that we perceive as continuous even though matter is synchronously oscillating between particulate Form and its energy equivalent in the Void. In this way sub-atomic particles remain implicitly and timelessly correlated. So do all atoms. All relative particle action takes place via the integrating quantum frame, called the Void, and this is synchronously timeless.
Relative motions introduce synchronous distortions as a result of relative space frame skipping with a corresponding accumulation of quantum energy equivalents in the Void. This accounts for relativistic effects but also introduces a small family of quantum forces, since accumulated energy must at some point find expression on the space frame side of the movie. These quantum effects are not transmitted as a force through space-time. They can only manifest synchronously with the projection of each space frame, and this is inconsistent with Newtons Third Law on a quantum scale. A new quantum-relativity emerges naturally that also accounts for gravitation. This offers a new and more meaningful methodology to the physical and biological sciences. There is more at www.cosmic-mindreach.com.
http://arxiv.org/...2428.pdf
http://superstrun...wing.gif
The phase was originally unaffected, but then without force but through the action of magnetic vector potentials, the phase was made to change. If the phase of the electron has changed, it seems sure that the momentum of the electron was, at the very least, momentarily affected.
In the case of the magnetic Aharanov-Bohm effect, it is clear and experimentally verfified that absolutely no force is required to change the phase of surrounding electrons. For instance, a transfomer or electric motor is often shielded so as not to produce large magnetic fields outside the enclosure, however, the magnetic vector potentials are a very fundamental force which do not decay at the same rate as the field.
Where the classical magnetic field has faded to zero, the magnetic vector potentials still exist and change the phase of charged particles. It seems clear that these vector potentials will interact most strongly with transition metals, especially those with only a single valence electron such as copper, silver and gold.
In addition, a highly permeable metal such as nickel will surely endure a change in electronic state. Where our biochemistry is guided by a complex interplay of electron transfer, particularly between transition metals, it begs the question, what effect do the magnetic vectors produce in the real world?
Or not? Can be some action, which influents the inertial reality be ever done without exertion of energy, i.e. some inertial force along certain path?
templeghost: Look at the effects of an MRI scan. No side effects whatsoever.
Has anyone conducted a study to see if multiple MRI scans increase the risk of rare blood cancers?
Why not start with the records of atheletes who frequently have MRI scans for sports related injuries?
They have absolutley no conception of what they are doing! Ask the people who work around intense magnetic fields what fantasies they tend to enjoy, you might be surprised how powerful the side effects are.