Saturday, March 3, 2012

Status of my paper on the origin of the magnetic and strong forces

I posted my paper, "Does Thomas precession cause rotational pseudoforces in particle rest frames?" (http://arxiv.org/abs/1108.4343) in August 2011 and updated it in early September 2011.  The update added the assessment of whether the kinematically-necessary anti-centrifugal force of the Thomas precession could plausibly correspond to the strong force that accounts for quarks combining to form nucleons.  As I described in earlier posts, it has been submitted to several journals, but not peer-reviewed.  Physica Scripta sent it out for review, but then withdrew it when the first referee objected because I called it a plausibilty argument.  Since then I've been working on a more convincing, particularly more relativistically precise, argument that I hope the journals will consider more suitable for publication.  It is taking quite a while to carry this out, but in the process I have found a number of flaws in the paper as currently posted that I want to acknowledge my awareness of.

Fixing the flaws in the paper will help make the next version more convincing, especially by removing the restriction of the current version to bound motion.   The approach I'm taking is not just to fix the flaws, however.  It is rather to present a completely rigorous electrodynamic analysis for general motion to order (v/c)^2 (and to (v/c)^4 in the case of circular bound motion), which is much more complicated than the minimally-relativistic treatment I posted on arxiv and previously submitted, and so is taking quite a while.

I'm still in the process of carrying out the analysis, and don't yet have a complete and convincing argument, but I have a few things I think are worth reporting prior to availibilty of a new version. 

I also want to mention that I found some related prior work after posting the current arxiv versions, and there is a paper that appeared on arxiv shortly after mine, by Royer (http://arxiv.org/abs/1109.3624), that also describes the magnetic force as the anti-Coriolis force of the Thomas precession.  One prior paper is by Bergstrom, "On the Origin of the Magnetic Field".  Another is "New perspectives on the classical theory of motion, interaction and geometry of space-time," by A. R. Hadjesfandiari. (http://vixra.org/pdf/1011.0058v1.pdf)

My interpretation of all of these papers is that they have a different perspective than mine.  They are concerned with the dynamics or kinematics of the particle experiencing a magnetic or general electrodynamic force and as mediated by a given electromagnetic field, whereas my approach is more oriented around a direct two-particle interaction, and the kinematical consequences of requiring physics to provide consistent descriptions from the point of view of various observers, in particular an observer moving with the particle that is the source of the field.  

The Bergstrom paper, from the early 1970s, attempts to explain the magnetic force as a Coriolis force.  The magnetic force however is  properly an anti-Coriolis force (in that it accounts for the absense of a Coriolois force in the rest frame of the particle that is the source of the magnetic field).  Bergstrom can't get to this result however because he is using the incorrect formula for the angular velocity of the Thomas precession, as in Moller and many subsequent textbooks, which leads to a sign error.  This also hampered me for about three years, until I realized the sign had to be wrong, and then immediately after remembered that Malykin had said exactly that in his review paper (cited in my paper). 

Royer neatly avoids the problem of the what is the proper Thomas precession angular velocity, by doing the analysis directly with successive Lorentz transforms.  That leads to the correct interpretation that the magnetic force is an anti-Coriolis force.  However, Royer mentions that there is no anti-centrifugal force expected, as I agree for his approach.  That is, there is no anti-centrifugal force in the electromagnetic field.  The need for the anti-centrifugal force doesn't become obvious until one tries to describe an electrodynamic interaction in the rest reference frame of the source particle.



I found the Hadjesfandiari paper shortly after finishing the second (and currently-posted) version of my paper.  When I realized that the Lorentz force must be incomplete, omitting as it does both anti-centrifugal and anti-Euler forces, I googled "Lorentz force incomplete" and turned it up.  (It is from late 2010 and so is prior to mine being posted, although there is evidence on the web of me having the basic idea in the summer of 2008.  That was when I noticed that the expected Coriolis force on a moving charge in the rest frame of a charged particle (of equal mass) has the same form and magnitude as the magnetic force.) 


Now about my paper, the first thing I want to mention is that I now believe that the restriction I made to bound motion was based on an error of understanding and is unnecessary.  It seemed at the time though to solve a problem I was having with getting the magnetic force to equate exactly to the anti-Coriolis force of the Thomas precession.  The problem is that in the laboratory frame where (say) the center of mass of two interacting charged particles is stationary, the magnetic force on either particle depends only on the velocity of that particle relative to the local magnetic field.  The source-particle velocity enters through the magnetic field, but not in the interaction of the other particle with the magnetic field.  But, in the source-particle rest frame the expected (but absent) coriolis force is based on the relative velocity of the non-source particle to the source particle, which is equal to the velocity difference between the particles in the lab frame.  This led to some stray terms that made the analysis seem incorrect, but I could see they would vanish for bound motion, so I decided to make that assumption in order to get a working paper. Now however I am fairly certain that those extra terms are just part of the electrodynamics in the lab frame.  Showing this will be something that makes my whole thesis much more convincing, but I am still working out the details.  Since there is of course no restriction to bound motion in the laws of electrodynamics, it isn't very good to have to make it for my argument that the magnetic force is an anti-Coriolis force of the Thomas precession.


Another flaw with the current version of my paper is that it fails to be sufficiently cognizant of the general necessity of including the anti-Euler force.  I mention that there must be an anti-Euler force, and that there isn't one currently in electrodynamics (although it may correspond to the weak force), but I failed to take to heart that it needed to be included in the analysis unless the motion is restricted to zero radial motion between the particles.  The next version will be at least cognizant of this fact, and possibly may include the anti-Euler force explictly to order (v/c)^2.  I have tentatively obtained a description of it to order (v/c)^2, which I would like to publish as soon as possible.  It's quite simple to describe to this order, although it has a very complex description when higher order terms are included.  These high-order terms will become significant at nuclear scales, which opens up the possibility of the anti-Euler force accounting for the weak force, which also has a complicated description and is significant only at nuclear scale.  However the anti-Euler force if I have things right also has a effect at order (v/c)^2 that I'm very eager to incorporate in my positronium atom model, as I have mentioned in at least one other post here.  At order (v/c)^2 the anti-Euler force can be relevant at the atomic scale.

Still another problem with the current version is that it isn't sufficiently careful about keeping the order of the analysis consistent. This leads to a confusing and unconvincing handling of the centrifugal force. The centrifugal force is an order (v/c)^4 effect, while the magnetic force is a (v/c)^2 effect, so it would have been better to throw the former away sooner than to carry it along as long as I did. On the other hand, working the analysis at order (v/c)^4 is complicated but possible in the case of circular motion (where the delay equation can be solved exactly), and it becomes clear that the Lorentz force as we know it today does not account for the needed anti-centrifugal force. This is an analysis I hope to include in a future version, but it may not be the next. Getting everything to work out exactly at order (v/c)^4 has eluded me so far and I don't want to hold up the next version just for that.


Finally, I might mention that thanks to a friend I'm now aware of a pedagogical write-up on the Thomas precession (in use at UC Berkeley) that explicitly states there is no centrifugal force experienced by an observer in a Thomas-precessing frame, due to the Thomas precession (http://bohr.physics.berkeley.edu/classes/221/0708/notes/thomprec.pdf.)  This answers the titular question of my paper in the negative.  The question was really only meant to be rhetorical, in any case. I think it should be rather obvious that if the Thomas precession is to be a non-trivial effect, it must not give rise to rotational pseudoforces in the particle rest frame.  The point of asking the question was that if there are indeed no rotational pseudoforces in Thomas-precessing particle rest frames, kinematics requires the presence of compensatory forces in the inertial laboratory frame.  Seeing the statement explicitly in teaching materials should be justification for somebody to ask what are the kinematical implications of the absence of centrifugal forces.  I believe they are profound and warrant further attention.

Why the links no longer work

Many of the links to the literature on this blog's homepage no longer function, unfortunately, because of an apparent clamp-down by the original journals, or at least some of them, which forced the people operating the sites where they resided to take them down or behind a firewall. 

I think it is especially unfortunate that the journal publishers are so touchy in the case of the sort of physics literature relevant to my work.  It is often decades old and probably not of very wide interest.

Monday, February 6, 2012

A hint of quantization as a classical-physics consequence of intrinsic spin


Equation (1) is a requirement that must be satisfied in order for the total angular momentum of the quasiclassical positronium atom to be a constant of the motion, assuming that the electron and positron are initially oriented so that their components perpendicular to the orbital angular momentum are anti-parallel.  In Eq. (1), L is the vector total orbital angular momentum (the sum of the orbital angular momenta of the electron and positron), n is a unit vector in the direction from the positron to the electron, and the intrinsic spin vectors are s.  The subscripts on the spin quantities indicate whether the spin is that of the electron or positron, and further whether it is the vector component parallel or perpendicular to L.


Equation (1): A condition for constancy of total angular momentum
Equation (1) is fairly easily obtained based on Thomas's equation of motion of the spin (which can alternatively be obtained from the Bargmann-Telegdi-Michel covariant equation of spin motion) specialized to the positronium atom, as is done in my positronium paper separately for the electron and positron, and then taking their difference to obtain an equation of relative motion for the spins.  Then putting in the initial condition that is the main result in my positronium paper, that antiparallel L-perpendicular spin components are a condition for total angular momentum constancy, Eq. (1) results.  If Eq. (1) could be satisfied at all points on the orbit (that is, as the vector n traces out the relative particle positions around the orbit) then the needed relative orientation would be maintained and constant angular momentum would be maintained.  (Total angular momentum constancy is in turn a necessary condition for nonradiativity.)   

To understand how Eq. (1) comes close to obtaining a quantum condition from classical electrodynamics with intrinsic spin,

Saturday, January 28, 2012

How Existence of Intrinsic Spin Might Explain the Non-Classical Character of Atomic Radiation

Bohr's Correspondence principle tells us that in the limit of large quantum numbers, quantum physics will agree with classical physics. For example, the simple Rutherford atom model of hydrogen, where a point charge electron orbits a point charge proton in a classical Keplerian orbit, will increasingly agree with observation, in terms of rate of radiative decay and frequency of transition radiation, as the electron orbital energy and angular momentum is raised. (The study of so-called Rydberg atoms, that is, atoms where the outer electron is excited to a high energy level compared to the rest, confirms this.) The frequency of the electromagnetic radiation becomes in the limit of large quantum number simply the frequency of revolution of the electron in its classical orbit. The rate of energy loss is also calculable from the radiation intensity predicted for an accelerating point charge according to classical electrodynamics.

At lower energy levels, and apart from the issue of quantized energy levels, the classical model of radiative decay of the system of bound point charges deviates significantly from observation. There are at least two obvious differences from what the classical model predicts. The transition time between two defined energy levels is less than the classical model predicts, and the frequency of the radiation is inconsistent with the classical expectation. The classical expectation is that the radiation of decay between two energy levels will start at the orbital frequency of the higher energy level and end at the (higher) orbital frequency of the lower. Observation however shows that transition radiation is essentially monochromatic, with the frequency predictable based on simply the energy difference between the levels. These seemingly inexplicable differences with the expectations of classical physics led to some despair at the time of their discovery. The initial triumph of quantum theory, even the early quantum theory of Bohr and Sommerfeld, and later the modern version developed particularly by Heisenberg, Schroedinger, and Dirac, was its ability to accurately describe atomic spectra including these features.

Sunday, January 22, 2012

Understanding the Origin of Quantum Behavior by Study of the Positronium Atom

For several years now I have been of a belief that if there is an explanation of quantum behavior in the classical electrodynamics consequences of the existence of intrinsic spin, then the Positronium atom is the ideal system for its elucidation. This belief grew out of my study of spin-orbit coupling in the quasiclassical hydrogen atom,

Saturday, January 7, 2012

Status Update

I am disappointed that Physica Scripta has withdrawn my paper from consideration after receiving a response from only one referee. That referee observed that I state in my concluding remarks that the analysis should be taken as only a plausibilty argument, and therefore it should not be published on that grounds alone.

I want to say that although I do consider that paper to be only a preliminary analysis, and that there are relativistic effects omitted that could negate it (which is why I say it is only a plausibilty argument) it is nonetheless a quantitative argument that both the magnetic and strong forces are direct consequences of the Thomas precession. As such I believe it is of sufficient interest to warrant publication in its own right, or at least review.

That said, I'm not entirely upset because it was just my first attempt, and the next will be much more relativistically precise.

Saturday, November 5, 2011

Status Report, and an Old Review

My paper linked in the previous post was sent back without review by Physics Letters A. This is what the general physics editor said:


Dear Mr. Lush,

I regret that your article is not suitable for publication in Physics Letters A as it does not satisfy our criteria of urgency and timeliness. Please consider submitting your work to a regular journal having a more pedagogical bias.

Thank you for submitting your work to our journal.

Yours sincerely,
(the general physics editor)


I then submitted it to Physica Scripta. Their status shows it sent out to three referees, as of a week ago, with one already having returned a report.

Meanwhile, here is an old review for amusement, of essentially version 3 of my paper about L. H. Thomas' 1927 paper: http://arxiv.org/abs/0905.0927v3

The journal is Studies in the History and Philosophy of Modern Physics.