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Duda Jarek

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  1. First of all, I totally agree that considering living things with fundamental physics is extremely inconvenient ... but it doesn't mean that there can be a contradiction between these totally different points of views. The problem you are talking about is mainly the conflict between: - looking time asymmetric 2nd law of (effective) thermodynamics and - CPT symmetric more fundamental physics. The main purpose of this thought experiment is to understand why there is no conflict here - that surprisingly 2nd law is also time-symmetric - depends only on reason-result chains ... which usually provide us with mugs from the past, so they can break only toward the future. Inside the rocket everything would be normal - but from our time perspective their mugs would break backward ... if they would provide such mug to the Earth, 2nd law would still give it tendency to increase entropy (break) - but this 'mug from future' could only break toward our past - in opposite direction to our 2nd law. If you don't like human origin mugs, you could e.g. crush a boulder or mix two different liquids - also a result of some reason-result chain (like liquid separation), what is the base of 2nd law. Simpler objects like a uniform liquid are thermodynamically time symmetric or reversible like many phase transitions. Secondly, it doesn't necessarily need to be a spacetime loop - ending points can be shifted in time, like in Hadley's peer-reviewed paper. I personally don't see it too realistic, only as thought experiment to understand thermodynamics, but you could get such loop for example by attaching mirror image to the left of black hole picture: Thirdly, why do you see here some exception of laws of physics?? It was intended to understand them, not contradict ... I completely agree that one couldn't go back and kill his grandfather - physics wouldn't allow him. The only natural for GRT point of view is the Einstein's block universe or eternalism ( http://en.wikipedia.org/wiki/Eternalism_%28philosophy_of_time%29 ) - that spacetime is already chosen - such that eventual time-loops would be already self-consistent. ps. The author of mentioned paper refers a few peer-reviewed ones, for example in Sorkin R D 1977 J. Physics A 10 717–725 there should be constructed a non-orientable wormhole (asymptotically flat), but it's not accessible electronically.
  2. There is some thought experiment constructed to help finding intuitions about the 'conflict' between CPT conservation and 2nd law of thermodynamics. Like for wormhole loops, I see it completely unrealistic - I only think it is inspiring mind exercise and may lead to some better understanding of thermodynamics (and temporal logic). General Relativity Theory determines shape and rotation of light cones in each point of spacetime (like near black hole), but it is time (and CPT) symmetric - doesn't directly distinguish between past and future of such light cones. Without any additional reasons like entropy gradient, we could time-flip the light cones. Another from 2nd law of thermodynamics way to distinguish past and future of such light cones is by continuity ... but let us imagine there is some loop on which GRT makes that light cones have configuration like that: Where the start and the beginning have the same position, but may be shifted in time. Of course it would require some really nasty singularity inside such loop - even more than in the center of black hole where spacetime is no longer a manifold. There are rather completely no reasonable scenarios to obtain such singularity, maybe mathematics could forbid such global solution. Here is some 2002 paper from Classical and Quantum Gravity Journal about nonorientable specitime (precisely not time-orientable), here is its arxiv version. They are probably completely unrealistic, but only for this thought experiment let us assume for a moment that there exists such time reversing loop - and a rocket flied through it and returned back to Earth orbit. If someone really doesn't like such loop concept, one can imagine that this rocket was transformed by CPT symmetry - it would be made of antimatter, but it would be enough for thermodynamical considerations. Ok, let's get to the main subject - thermodynamics. Inside this rocket, the astronaut shouldn't feel a difference - he could e.g. just break a mug ... but from our perspective it would be time reversed: pieces would get together into the mug. Everything (like mugs) have tendency to get into higher entropic state (broken), but our things (mugs) came from past reason-result chains, so such state change (breaking) can only have e.g.: unbroken state toward past time direction and broken toward future. In contrast, reason-result chain of mugs from the rocket came from our future time direction, so it can increase entropy only while breaking toward our past. So it seems that 2nd law doesn't only emphasize just e.g. entropy gradient direction, but can work in both - depending only on reason-result chains ... ? This thought experiment becomes real mind feast if we allow the astronaut to land (not antimatter case) Time reversed molecules are nearly the same, temperature is average energy so it also shouldn't depend on time direction - he should be able to just breath in our atmosphere (??) His body should be in thermal equilibrium with environment - heat exchange should work normally, so I don't see a reason his time-reversed metabolism should work improperly (??) So it would seem that he could also eat our food ... but there appears a problem - from his time perspective, it could need turning e.g. back into a chicken The situation is really really strange - great mind exercise - I would gladly hear your comments, expansions ... I think the only reasonable causality understanding here is Einstein's block universe - that like in GRT, the spacetime is already created and 'we only travel to our future there'. So eventual time-loops are already made self-consistent, like in good SF movies (e.g. Twelve monkeys) - if one would like to kill his grandfather in the past, there would happen something that he couldn't do it. If you disagree, how do you understand the conflict between CPT conservation and 2nd law? How would look such contact of time-opposite natural reason-result chains? (theoretically allowed by CPT conservation) For example some believe in cyclic universe model - that our universe will finally collapse into nearly a point. From the perspective of CPT conservation, such Big Collapse point would be Big Bang it reversed time - low entropy state (spatially localized) creates entropy gradient (2nd law), starts reason-result chains ... and so evolution of universe in reversed time direction ... which should finally meet with ours in some far far future. Why against current acceleration growth, it should finally start collapsing? Because of energy conservation - gravity pulls together (1/r^2), while some 'dark energy' push it out, but its density (and so strength) should decrease with the volume (1/r^3) ...
  3. If someone is interested, I have just finished large paper about MERW and its connections to quantum mechanics (e.g. to show these results on congress on emergent quantum mechanics this weekend) - a preliminary version of my current PhD: "Surprisingly the looking natural random walk leading to Brownian occurs to be often biased in a very subtle way: usually refers to only approximate fulfillment of thermodynamical principles like maximizing uncertainty. Recently, a new philosophy of stochastic modeling was introduced, which by being mathematically similar to euclidean path integrals, finally fulfills these principles exactly. Its local behavior is usually similar, but may lead to drastically different global properties. In contrast to having practically no localization properties Brownian motion, this recent approach turns out in agreement with thermodynamical predictions of quantum mechanics, like thermalizing to the quantum ground state probability density: squares of coordinates of the lowest energy eigenvector of the Bose-Hubbard Hamiltonian for single particle in discrete case or of the standard Schrodinger operator while including potential and making infinitesimal limit. It also provides a natural intuition of the amplitudes' squares relating to probabilities. The present paper gathers and formalizes these results. There are also introduced and discussed some new expansions, like considering multiple particles with thermodynamical analogue of Pauli exclusion principle or time dependent cases, which allowed to introduce thermodynamical analogues of momentum operator, Ehrenfest equation and Heisenberg uncertainty principle." It should appear on arxiv soon, now it can be download here: http://dl.dropbox.com/u/12405967/phd2.pdf I would really gladly discuss about it and would be grateful for any comments
  4. There is extremely interesting yesterday's NASA announcement: http://www.nasa.gov/mission_pages/voyager/heliosphere-surprise.html Voyager has found bubble-like foam of magnetic field lines (flux ropes/vortex lines?) coming from our Sun: "(...) "The sun's magnetic field extends all the way to the edge of the solar system," explains Opher. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are now, the folds of the skirt bunch up." When a magnetic field gets severely folded like this, interesting things can happen. Lines of magnetic force criss-cross, and "reconnect". (Magnetic reconnection is the same energetic process underlying solar flares.) The crowded folds of the skirt reorganize themselves, sometimes explosively, into foamy magnetic bubbles. (...)" ps. Here is recent PRL article about laboratory experiments of magnetic flux ropes: http://prl.aps.org/abstract/PRL/v105/i7/e075005
  5. I wanted to add that there is conceptually very similar soliton electron model developed for 20 years by prof. Manfried Faber from Vienna: http://arxiv.org/PS_cache/hep-th/pdf/9910/9910221v4.pdf Instead of three axes of ellipsoids, it has only one - the field in vacuum is from 2D sphere (direction space of 3D), which is equator of abstract 3D sphere, but getting out of the equator costs (Higgs-like) potential energy (instead of deforming in ellipsoid field). Dynamics of directions in vacuum effectively becomes electromagnetism - in his paper there is very throughout explanation of that (muuuuch better than in mine). So having hedgehog field configuration for charge, to glue this field to the center, it has to get out of the equator to one of 2 poles of 3D sphere - choosing +- spin of electron and giving it rest energy (becoming also inertial energy thanks of Lorentz invariance). In ellipsoid field the two additional perpendicular axes give one additional degree of freedom - representing quantum phase required for wave nature - it rotates as soliton's internal clock. Professor invited me and we talk a lot - he doesn't like the internal clock concept and he would like to avoid it. These additional axes also make the family of solitons grows up to menagerie from our physics ...
  6. Quantization of magnetic flux going through superconducting ring is explained that along this loop, quantum phase (order parameter in this case) has to return to the initial phase, so it makes integer number of full rotations - this number determines the total magnetic flux going through this loop (integer multiplicity of 2.067 833 667(52)×10^-15 Wb), like on this picture: There appears natural question - why we couldn't take this argument into just a loop in vacuum? In static picture, we should be able to decrease such abstract loop down to having single flux quant going through it and so they seem to be physical lines in space. These natural consequences of quantum mechanics are called 'vortex lines' by prof. Bialynicki-Birula (well known in Poland). Very similar concepts are popular in considerations of corona plasma of our Sun. There is generally a problem for standard MHD models to explain that while the surface has thousands of kelvins, for corona it exceeds million kelvins ('coronal heating problem'). The hope could be the observed magnetic flux ropes (some paper with such explanation, or different Physorg news) - charged particles instead of just repelling each other, gathers in nearly one-dimensional objects along magnetic lines, which carries very large energy released mainly while magnetic reconnections. Such lines should have large energy density per length, so in low temperatures we could expect them rather only in microscopic scales. Quantum rotation operator suggests that such lines should go through fermions along their spin axis - it could explain their tendency to couple (electrons in orbitals, Cooper pairs, nucleons in nuclei), but also suggests how optical photons looks like: topology says that to destroy such couple for e.g. deexcitation, we should twist one of them 180 deg - changing its spin by 1: like from 1/2 to -1/2. Such twist is angular acceleration then deceleration - angular momentum conservation suggests that there should be created kind of EM wave 'carrying this 180deg rotation' ('have spin 1'), it could also help destabilizing other excited couples (stimulated emission) - we get optical photon candidate: Accepting such 1D structures also allows for other particle-like constructs, for example if on such vortex line there would be additional 'rotation toward the center of line', it would get charge and it would change it into opposite vortex line (became magnetic dipole) - we would get lepton-like construct (pictures). Could (some?) magnetic flux lines be physical objects? Is something like corona's magnetic flux ropes observed also in plasma experiments - that against Coulomb repulsion, charged particles have tendency to gather on lines along magnetic field? Would it affect stability of e.g tokamaks?
  7. I had to check what 'strawman argument' means ("A straw man argument is an informal fallacy based on misrepresentation of an opponent's position(...).") - at the end of that discussion you write "Yes, it is interesting. But it fails to work in fatal ways." supporting the last sentence by that for nucleus without magnetic moment, there would be no Lorentz force to repel electron - I've replied that there is also magnetic field of thousands times larger magnetic moment of electron (this is the Lorentz force used in that model), but I didn't get any further reply? Please explain why do you think I've misrepresented your position? (but let's take it back to that discussion) Question from this thread is looking important extremely general question - if you don't like microscopic scales, let's imagine we have bar magnet traveling in electric field ... again we could center reference frame on the magnet for a moment and now the charged object is traveling in magnetic field generated by the magnet ... So let's forget about the 'speculative' microscopic use in this thread - what do you generally think of existence of such force? Dipole can be seen as made of two near monopoles - if you don't think such force exists for magnetic dipoles, what about for eventual monopoles (I can find you some papers about it)? ps. Quantum mechanics was built on classical one, so there should be some quantum effects corresponding to the last term from Lagrangian above (making Bohr's orbits unstable) - atomic spin-orbit interaction seems to be one of them (?)
  8. Physical effects relating electric and magnetic properties have sometimes 'dual' analogues - with exchanged places. For example in Aharonov-Bohm effect, the phase of charged particle depends on side of magnetic flux tube it comes through, while in its 'dual' analogue: Aharonov-Casher, the particle has magnetic moment and tube contains line of charge (it was used e.g. for neutron interference). Another interesting 'dual' effect (hypothetical) can be found in magnetic monopole Wikipedia article - full expression for Lorenz force in such case would be: [math]\mathbf{F}=q_e\left(\mathbf{E}+\frac{\mathbf{v}}{c}\times \mathbf{B}\right)+q_m\left(\mathbf{B}- \frac{\mathbf{v}}{c}\times \mathbf{E}\right)[/math] where [math]q_m[/math] is magnetic charge - the last term corresponds to magnetic monopole - electric field iteration. The question is if we should expect similar term for not only magnetic monopoles, but also for much more common: magnetic moments(dipoles)? I would say that yes - for example imagine classical electron traveling in proton's electron field - let's change reference frame such that for infinitesimal time electron stops and proton is moving in also magnetic field created by quite large electron's magnetic moment - because of 3rd Newton's law, resulting Lorentz force should also work on electron ... (3) equation here is Lagrangian for such electron's movement: [math] \mathbf{L} = \frac{1}{2}m\mathbf{v}^2+\frac{Ze^2}{r}+\frac{Ze}{c}\left[ \mathbf{v}\cdot\left( \frac{\mu\times \mathbf{r}}{r^3}\right)\right] [/math] where the last term would correspond to such eventual magnetic moment-electric field interaction. But in recent discussion, swansont's only counterargument was based on that such force doesn't exist... So I wanted to ask if this looking quite important force is true or not? If true, it seems to be completely forgotten - there would be needed some better sources ... have you seen something like that in a book or paper?
  9. Ok, let me take some basic description here ... maybe it will help with discussion ... Let's start with ellipse field - there is an ellipse in each point of 2D plane, which prefer some shape (2 radii) because of potential. Mathematically - there is tensor field - real symmetric matrix in each point, which prefers some set of eigenalues being constants of the model (its eigenvectors represent ellipse axis of radius being corresponding eigenvalue). Now here are two simplest topologically nontrivial situations for such field: looking at loops around such points, 'phase' make some mulitiplicity not of full rotations like we would expect for vector field, but thanks of ellipse symmetry - some multiplicity of 1/2 rotations - singularities from picture have index/spin +1/2, -1/2. On such loop, there are achieved all possible angles of ellipse axis - while looking at smaller and smaller loops down to a single point, we see that in some moment these entities have to loose directionality - in this case ellipses have to deform into circle (two eigenvalues equalize). This enforced by topology deformation means that we get out of potential minimum - soliton chooses minimal energy for this topology, which is nonzero - it has rest energy (mass), which can be released as nontopological excitation (photons) while annihilation with antisoliton. This mass creation mechanism is based on that potential minimum is topologically nontrivial (circle) - exactly as in Higgs potential: Mexican hat ((|z|^2-1)^2) - if on a circle the field achieves all values from the energy minimum (|z|=1), inside this circle it has to get out of the minimum, giving soliton mass. Such solitons create/are strong deformations of the field - standard energy density of such field increase with its variousness - taking opposite solitons closer (the same further) make the field less various - give them attraction(repelling) force - it can be see using this demonstration. Ok, let's go from ellipse field used e.g. by 'singular optics' as representing light polarization to 3D ellispoid field in 3D. Now singularities as previously create 1D constructs - vortex line/spin curve. We can make them in three ways - choose one axis along line and remaining two make singularitiy equalizing these 2 eigenvalues. Now they have mass/energy density per length, which generally should be different in these 3 cases - let's call them electron/muon/tau spin curves correspondingly. By synchronous rotation 90deg of axes along such line, they theoretically can transform one into another. Loops made of something like this are extremely light (comparing to further excitations), very weakly interacting and generally can transform one into another - we get 3 families of neutrinos. Now if along such 1D construction, axes rotate toward/outward, we get charge-like singularity on it, transforming spin curve into opposite one, like on this picture: in such more complicated singularity, now topologically all three axes have to equilibrate in the center, giving it much larger rest energy (mass) - we get three families of leptons. Alternative view on such singularity is by looking at axis along curve - it's for example targeting the center while such singularity, so looking at perpendicular submanifold which is nearly sphere now, we have to align somehow remaining two axes there - hairy ball theorem says we cannot do it without singularity - or in other words: that electron has to have also spin. Further excitations is making loop with additional twist along it, like in Mobius strip - in center of something like this appears really nasty topological singularity requiring much larger ellipsoid deformations and so giving these unstable meson-like structures larger mass. Then there are knots - loop around curve of different type - now on inside curve phase make 1/2 rotation, while on the loop it makes full rotation - enforcing nasty deformations on their contact - we get even heavier constructions: baryon-like. Some integrated irregularity of inside curve could make such combination easier and so proton has smaller mass than neutron. Now if we have two loops around one line, they generally repels each other, but the energetic income of having charge, make them get closer to share the charge - getting deuteron with centrally placed charge (like on this picture). Further nucleons can also help holding their structure by creating/reconnecting loops - creating complicated interlacing structures like here: While deep inelastic scattering, such mesons/baryons seem to be made of 2/3 regions. Weak interaction here corresponds to spin curve structure, while strong to interaction between two such structures - they work only on specific for these constructions distances (asymptotic freedom). Far from singularities, ellipsoids have fixed shape and so the only dynamics is through their rotations - it occurs that such spatial rotations can be described using Maxwell's equations - we get electromagnetism and situation around singularities gives them magnetic flux/charge. To get full spacetime picture, we have to use 4D ellipsoids in 4D instead - fourth axis correspond to local time direction (central axis of light cones) and has energetically strongest tendency to align in one direction - in such case we would get pure EM as previously, but small rotations of this axis gives additionally second set of Maxwell's equations - Lorentz invariant gravity (called gravitomagnetism) - in this picture spacetime is flat and what is curved is space alone - submanifolds orthogonal to time axis. ... Questions? Comments? Counterarguments? -------------- ps. If someone is interested, I believe here has finally started a really discussion about ellipsoid field: http://www.sciforums.com/showthread.php?t=106416 -------------------------------------------- Far from particles, the only working interactions are electromagnetism and gravity - taking a (e.g. 1 fm radius) sphere around a particle, the situation of these two fields fully describe charge, magnetic moment and gravitational mass inside. We know that charge (and spin) is quantized - directions of electric field around charge are in 'hedgehog configuration', what is called topological singularity, among which there also appears natural quantization of topological charge - how much time the projection from sphere to sphere of directions of field values covers the sphere (Conley index). The problem with these two interactions is that if we would like to just extrapolate them to the center of sphere, it becomes nonphysical - goes to infinity, and its direction cannot be defined in the center. So to remain physical, these interactions just have to deform somehow to be able to glue together in a continuous way without infinities ... and we have additional interactions which work only in such regions (weak/strong) - so maybe they are just two faces of a single interaction (GUT) ... ? We can look at ellipsoid field model of e.g. electron as just a trial of such gluing surrounding EM field in physical way and the required going out of energetically preferred EM interaction, leads to some rest energy prisoned there (mass). To summarize, we can look at this field as a way to fulfill natural requirements: - which in vacuum becomes electromagnetism (and gravity), but to glue it without singularities in particles, it can look like a different interaction (weak/strong), - which leads to quantization of spin, charge and other quantum numbers (e.g. on topological level), - these quantum numbers should identify field configuration - particle (even distinguish between long/short living neutral kaons ...), - field configuration of particle should be usually in the lowest energy state for these given constrains (quantum numbers) – this rest energy is their mass (through Lorentz invariance becomes also inertial mass and should deform gravitational field to became also gravitational mass)... Another requirement for such models could be forgotten de Broigle's doctoral thesis concept: that with particle's energy: E = mc2 comes its internal periodic motion: E = hf It is remained in very interesting Hestenes paper, in which he also describes recent experimental confirmation of this effect (called e.g. zitterbewegung). For example while particle moves, the first relativistic correction of its mass is [math]m\sqrt{1+v^2}\approx m+mv^2/2[/math] So movement increases frequency, leading to additional phase shift proportional to [math]\int pvdt = \int p dq[/math] Requiring that while particle makes a loop, its internal phase returns to initial one, gives Bohr's quantization condition. Such internal periodic motion creates also periodic wave-like perturbations of surrounding field - giving localized entity also wave nature ... There are extremely interesting recent papers of Couder, Fort et al. in which they experiment with macroscopic entities having similar wave-particle duality: about oil droplets on vertically vibrating liquid surface - constantly creating periodic waves around - interaction with these waves allows for 'quantum effects': interference, tunneling depending on practically random hidden parameters or orbit quatization condition - that particle has to 'find a resonance' with field perturbations it creates - after one orbit, its internal phase has to return to the initial state. Returning to ellipsoid field - looking at matrix allowing to represent its vacuum dynamics (rotations) as EM+gravity, electric field corresponds to spatial rotations while time evolution and gravitational field to small rotations of time axis (central axis of light cone) - so its particles have kind of two internal clocks: the first one has frequency proportional to electric charge and the second to gravitational mass.
  10. Looking at electron, there is singularity of electric field in it - its values seem to tend to infinity, but also directions create topological singularity ... This picture suggests that maybe we don't need some additional (out of field) entities for particles, but this construction of field itself is the electron - that particles are some characteristic localized constructs of the field, maintaining their structures/properties - are solitons. Skyrme used such constructions to model baryons, they automatically give particles masses (rest energy), allows for various number of particles because of annihilation/creation, there is corresponding attraction/repelling for opposite/the same ones, they have integer 'quantum numbers' ... For example here is nice animation of soliton/antisoliton annihilation which released energy gathered in them (mass) as analogue of photons: http://en.wikipedia.org/wiki/Topological_defect Anyway, the perfect situation would be finding a field which family of topological soltions corresponds well to the whole particle menagerie with their properties, decays, dynamics ... and which dynamics became electromagnetism and gravity far from particles (vacuum state). It occurs that extremely simple field: ellipsoid field surprisingly well qualitatively fulfills these requirements - just a field of real symmetric 3*3 (4*4) matrices, which prefers some set of eigenvalues - it can be seen as stress tensor or as less abstract skyrmion model, but with Higgs-like potential (with topologically nontrivial minimum) or as expansion of ellipse field of light polarization concept (considered by 'singular optics'). Rotating ellipse/ellipsoid by 180deg we get the initial situation, so the simplest constructions of such field have spin 1/2, like in this demonstration allowing also to see attraction/repelling caused by minimizing variousness of the field: http://demonstrations.wolfram.com/SeparationOfTopologicalSingularities/ In ellipsoid field in 3D we can choose these axes in 3 ways - we get 3 families of spin 1/2 constructs. There can be created charge-like construct on it getting 3 families of leptons (topology says that they need also to have spin). Then we get constructions like mesons, baryons which finally can join into something like nucleus. Qualitatively masses, properties, decay modes are practically exactly like in particle physics. Far from solitons dynamics becomes 2 sets of Maxwell's equations - for electromagnetism and gravity: dynamics of rotations of 3D ellipsoids (no gravity) gives EM and small perturbations of fourth axis of 4D ellipsoids (which has the strongest tendency to align in one direction) gives Lorentz invariant gravity (called gravitomagnetism). All of it can be basically seen on pictures - they start on 21 page (after motivations for considering solitons) of this presentation. It is described and derived in 4-5 sections of this paper. I'm going to make simulations some day, but I would be grateful for any constructive comments now - this model is very 'strict': we cannot just guess and add new Lagrangian terms as in standard approach - it's quite correct or just wrong: a single real qualitative problem would probably take it to trash ... What do you generally think of soliton particle models?
  11. swansont, if you agree that besides magnetic moment of nucleus, there might be also quite important thousands times larger electron's magnetic moment, I think you still need at least one concrete argument to support your claims that "it fails to work in fatal ways." ? Meanwhile, I was pointed out very interesting paper of prof. Hestenes in which he reminds forgotten de Broigle's doctoral thesis concept, which seems to originally motivated Schroedinger: that with particle's energy: E = mc2 comes its internal periodic motion: E = hf There is also recent experimental conformation of this claim by Gouanere et al mentioned there: for 80MeV electrons, one such period corresponds to spacing in silicon crystal and it seems they've observed such absorption (here is more recent different conformation of this zitterbewegung). Such internal periodic motion allows for wave-particle duality as literally observed for oil droplets in extremely educating papers of Couder, Fort et al - that because of some periodic motion, localized particles create periodic wave-like perturbation of the field around - interaction with these waves allows for 'quantum effects': interference, tunneling depending on practically random hidden parameters or orbit quatization condition - that particle has to 'find a resonance' with field perturbations it creates - after one orbit, its internal phase has return to the initial state. Interesting question is to understand relation with Gryzinski's explanation: using spin precession? Another interesting information could be that it occurs that prof. Bucher recently rediscovered free-falling atomic model even neglecting magnetic moments.
  12. Not true. Let's choose electron's reference frame for infinitesimal time - electron stops and proton is moving in magnetic field of electron's magnetic momentum - now look at Lorentz force and then use 3rd Newton's law ... Like Aharonov-Casher is dual to Aharonov-Bohm, charge in magnetic field is dual to magnetic moment in electric field. Nucleus magnetic moment is a few thousands times smaller and so hyperfine corrections are.
  13. mississippichem , the main Lorentz force here is caused by electron's magnetic moment, so everything 'works' also with I=0. But if nucleus has nonzero magnetic moment, there appears additional complicated correction - mainly attraction/repelling while electron misses nucleus - the alignment of nucleus spin is important - maybe G didn't calculated this, but why do you think there is a problem with hyperfine splitting here? Anyway, he made a really huge work, but I agree there still left a lot to do ... but you seem to have some deeper reason to belief that such path of getting as much as possible from understandable: classical approximations is just senseless - what is this reason?
  14. As I've said, I have no experience about this model - I remember he used this plane picture allowing for spin-polarization to explain Stern-Gerlach experiment, but I don't know if e considered e.g. Zeeman effect - I believe there still have left a lot to do. Complex object means built of at least two e.g. particles, like atom - angular momentum conservation says that without external interaction, total angular momentum of such object has to be preserved. And so if while free-falling total angular momentum of atom is zero, it has to remain that way. About quantization of nucleus - this complex object has own magnetic moment and it seems natural that it should somehow synchronize with electrons - leading to their common quantization... ? Looking at 2nd picture of his 4th lecture you've linked, the main Lorentz force seems to be caused by electron's own magnetic moment - nucleus spin has minor effect here. Oil droplets had rather to be electron analogy - suggestion that quantization is more general phenomenon and density clouds could naturally emerge on statistical level of localized entities - oil droplet is nice model of soliton: surface tension make it maintaining its shape. Quantization of localized objects means that its internal periodic process (like spin precession) has to make some integer number of periods while single orbit - it leads to analogy of Bohr quantization condition. If we would like to describe it statistically, beside probability there is also important relative phase of this internal periodic process - the phase of wavefunction describes it.
  15. swansont, since you were talking about angular momentum, I thought about atom's magnetic moment. In Gryzinski's hydrogen atom, electric dipole moment quickly change its direction, so that it vanishes while taking time average (and could help with cold fusion if we didn't make this average). I don't feel competent to comment it, but there is a lot about electric dipole/quadrupole/octupole moments in his papers about Ramsauer effect and chemistry - I don't believe he would considered such models seriously if there were serious difference in such essential experimental parameters like moments. I don't understand your objections about Stark effect - that electric field change energy of charged electron ... there is briefly presented calculus for it in his book, but it seems it wasn't published anywhere else. About hyperfine structure, it's extremely subtle effect ... I don't know if he considered it, but classically there is also a difference if two magnets/spins are aligned parallelly (repelling) or anti-parallelly (attraction) - this force drops like 1/r^4, but free-falling electron almost misses nucleus ... I see QM statistically emerging as time average, so it's perfect for modeling relatively static atoms like while considering energy spectrum. Gryzinski's reluctance to QM was based on its weak agreement in more dynamical situations he was working on - scatterings - they provide much more experimental data than energy spectrum. His classical scattering papers have hundreds of citings because it really worked better ... In WKB semicalssical approximation we start with classical one - why we cannot consider such approximation for electron in atom? Anyway, since you are attacking quite technical problems of this classical approximation, does it mean that you don't have any fundamental arguments against electron's corpuscular nature? Observe that while such free fall, the result of bounce strongly depend on conditions - so adding thermodynamical noise make that in fact 'Gryzinski's triangle' for hydrogen should fuzzy with time and finally its time average should became spherically symmetric. Another explanation is that the choice of the plane strongly depends on initial electron's condition - since e.g. these photos are made thanks of thousands of electrons, we get average over different planes. About zero angular momentum, since it is zero initially and there is no external source, it has to remain zero - like for cat turning while falling. ps. I've just read the last Couder's paper - they've observed Bohr-Sommerfeld quantization condition for ... oil droplets Looking at MERW-based stochastic models, I would say that they also should observe more general spatial Anderson's localization on irregular pool - for example time average shifted toward resonant modes on Sinai's billiard as in quantum chaos ...
  16. Dipole moment is created by electrons having angular momentum, while in Gryzinski's hydrogen angular momentum is zero - electron make free fall toward nucleus. In his papers he calculated (among others) many different moments and claimed to get really good agreement with experiment - he was doing related experimental research his whole life and it was this really good agreement what brought him to classical path. Even if you aren't satisfied with this agreement (QM approximations were worse) or you would find some errors in these peer-reviewed papers, you have to remember that they are still only approximations. If you want to prove that electron looses corpuscle half of duality near proton, you should rather have some deeper conceptual argument for this belief?
  17. I would like to join to Michel's question ... I though we get through 'momentum problem' in first posts (complex objects like cats or atoms can rotate with zero angular momentum)...? About dipole moments - Gryzinski for almost 20 years was the head of Polish hot plasma group (table on 7th page) and so he was extremely careful about such EM properties, which should be clearly seen in experiments he compared his models to...?
  18. I generally agree with the last posts of both lemur and swansont - the long and stormy history 'melted' dogmas and reasonable hypotheses ... we just have to base on some foundations, but obligation of people calling themselves scientists should be also the search for clear distinction between faith and science - being careful/pessimistic about unproven 'well known facts' - especially if they disagree with experiment ... or lead to logical inconsistencies - for example the coexistence of a few dozens essentially different 'valid interpretations' seems to be a strong suggestion - not to accept that Nature is illogical, but rather to question our dogmas. The central questions of this topic is about corpuscular nature of electrons in atoms - while e.g. semiclassical WBK approximation is about reaching QM basing on classical approximation and so trajectories, there is some kind of social certainty/taboo in trying to imagine quantum probability clouds as emerging from trajectories. Duality principle strongly suggests that electrons have simultaneously both natures, what is clearly seen e.g. in Afshar experiment. Looking at photos of atoms, we can see where in orbital electron was (localized?) before being tear off by potential. If we accept (used in EPR) precessive motion of electron's spin, there is periodic process involved with it - in some situations it's essential for electron to be somewhere (corpuscular nature) and sometimes it has to 'fit with phase' of its own periodic process (has wave nature). Please finally explain why you are insisting that we just cannot think of orbitals as emerging from trajectories?
  19. Again and again ... no, it's not my model ... no, it doesn't claim to be the ultimate theory, but only approximation and so please comment these concrete papers claiming that it approximates really well in many concrete situations, often better than quantum mechanical approximations ... What I feel qualified is to advocate that particle's duality has also corpuscular half and so it should approximately travel using classical trajectory - for example as the base of semiclassical approximation, hydrodynamical formulation. There is some kind of taboo of remembering about this half of duality while considering electrons near proton - and I cannot get from you a single argument supporting it ... So do you belief in corpuscular-wave duality: that particles are simultaneously both of them? How do you see this fundamental principle of QM? How do you apply it to electrons around proton?
  20. Classical trajectories cannot give perfect agreement, because they e.g. ignore/simplify extremely complicated communication between particles through the field, which for example allow for interference even for macroscopic localized entities like in linked Couder's paper (here is nice commenting article and more recent from MIT webpage) - analogous interference mechanism applies to particles being shape/structure maintaining constructions of field (soltions), which are much more complicated entities than classical particles - this is the view I'm advocating. While using so called WKB semiclassical approximation, in lowest Planck constant power order, we use classical mechanical solution - such trajectories are just approximation, which could be useful in context of some phenomenas ... like popular recently cold fusion, what motivated me to write the previous comment. I don't work on such classical approximations, but on their connection to quantum mechanics (this field is called quantum chaos), but if we are talking about accuracy, it's you who should comment e.g. having many hundreds of citings Gryzinski's paper in which he repairs weak agreement with experiment of quantum mechanical scatterings calculations, by using classical trajectories - what can be seen as the base of semiclassical approximation of QM: in situations when direct QM calculations became too complicated ... Once again - I'm not saying that QM is wrong and classical is right, but that there is deep equivalence between these picture - they are just different views, showing phenomenas from different perspectives ... I gave dozens of arguments for it - if you are sure that they cannot be just equivalent pictures, that e.g. electron near proton ultimately looses particle half of duality, please finally give a single concrete argument for such brave claims?
  21. Cold fusion is generally classified as fringe science and so I wasn't treating it seriously, but there was recently PhysOrg article about public demonstration of generating 12kW for half an hour from nickel+hydrogen by device in which such amount of chemical energy just wouldn't fit ... it's difficult not to be skeptical about such absolutely revolutionary claims, but it motivated me look closer at this field and so I became aware that there are thousands of papers about cold fusion, hundreds of groups reported excessive heat: http://www.lenr-canr.org/index.html If it's not just a massive scum of hallucinations, there is needed some theoretical explanation of such eventual low energy nuclear reactions - one of reasons of rejecting such possibilities was lack of theoretical understanding: used directly quantum mechanics says that probability of tunneling through such repelling barrier between nucleuses is completely negligible. But what if we can sharpen a bit quantum mechanical probability cloud of electron - try to imagine some movement of localized electron behind this picture ... Imagine such free-fall electron's trajectories which nearly pass nucleus - its electric field could pull proton behind ... straight to hit the nucleus - localizing electrons make cold fusion much more likely... And so Gryzinski write in his book that a few days after the Pons&Fleishmann announcement, he explained such phenomena as naturally appearing in his model and it was published in Nature a month later (April 1989). He was enthusiast of cold fusion, had a few papers about it and two patents. The main reason of reluctance to imagine particles as quite localized entities as seen while scatterings, seems to be the interference phenomenon. But QM doesn't have monopoly for interference - it's completely natural also in classical physics like on water surface ... or I've just found PRL paper reporting interference of macroscopic droplet: http://prl.aps.org/abstract/PRL/v97/i15/e154101 If we accept particles as shape/structure maintaining localized construct of the field (solitons), there is still interference expected for them - just decompose them into plane waves using Fourier transform and (in linear approximation) plane waves interfere. It's just that soltions are far from the concept of (various number of) classical particles - there is also extremely complicated communication between them going through the field causing e.g. interference effects. Generalizing this picture into more trajectories leads to Feynman's path integral formulation of quantum mechanics. Classical trajectories can be seen as some useful approximation, for example the base of semiclassical approximation or ... stochastic perturbation - alternative view on such practically randomly perturbed trajectory is that in such case the safe is to assume Boltzmann distribution among possible paths, what as in euclidean paths integrals, leads to transformation of classical trajectories into 'near' (overlapping) quantum eigenstates (presentation) What do you think about the possibility of cold fusion and of localized particles?
  22. I defended my PhD in computer science (now in progress in physics ), which half was was about this new approach to data correction - basically it's extended convolutional codes concept to use much larger states (which require working not on the whole space of states as usual, but only on used tree of states and allows to practically complete repair in linear time) and using entropy coder to add redundancy (simultaneous data compression and rate can be changed fluently). The thesis is the paper from arxiv with a few small improvements ( can be downloaded from http://tcs.uj.edu.pl/graduates.php?degree=1〈=0 ) Here is presentation I've used - with a few new pictures which should make understanding concepts (and asymmetric numeral systems) easier and e.g. some comparison to LDPC.
  23. Brownian motion requires relatively large 'walker', which is constantly being pushed in random directions (no memory) - it's derived as infinitesimal limit of Generic Random Walk (GRW) on a graph(lattice), in which each outgoing edge is equally probable. But let's imagine we want to estimate probability density of positions of some entity which doesn't just constantly 'stop and make new independent decision', but make some concrete trajectory, which for example could depend on the past (by e.g. velocity) - in such situations the safer than taking statistical ensemble among single edges as in GRW/Brownian motion, should be using statistical ensemble among whole possible paths. The simplest such model is Maximal Entropy Random Walk (MERW) on graph, it can be defined in a few ways: - stochastic process on given graph which maximizes average entropy production, or - assuming uniform probability distribution among possible paths on graph, or - for each two vertices, each path of given length between them is equally probable. Obtained formulas are: P(a->b ) = [math] \frac{M_{ab}}\lambda \frac {\psi_b}{\psi_a} [/math] where M is graph's adjacency matrix ([math]M_{ij}\in{0,1}[/math]) lambda is its dominant eigenvalue with psi eigenvector (real, positive because of Frobenius-Perron theorem) [math]M \psi=\lambda \psi [/math] stationary probability distribution is: P(a) is proportional to [math](\psi_a)^2[/math] This stochastic process is Markovian - depends only on the last position, but to calculate these transition probabilities we just have to know the whole graph - we should think about this probabilities not as that 'the walker' uses them directly, but that they are only used by us to propagate our knowledge while estimating probability density of his current position. (Minus adjacency matrix) occurs to correspond to discrete Hamiltonian, so while GRW/Brownian motion spreads probability density almost uniformly, MERW has very similar localization properties as quantum mechanics. While adding potential: changing statistical ensemble among paths into Boltzmann distribution and making infinitesimal limit of lattice constant, we get stationary probability density exactly as quantum mechanical ground state (similar to Feynman's euclidean path integrals). Here is PRL paper about MERW localization properties: http://prl.aps.org/abstract/PRL/v102/i16/e160602 Here is my presentation with e.g. 2 intuitive derivations of MERW formulas and some connection to quantum chaos: http://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0B7ppK4I%20yMhisYmI3YTAzNzYtMDkyNy00ZDAxLTg1NGEtOTg4NWNkYzU3M%20jQ1&hl=en Here is simulator which allows to compare conductance models using GRW and MERW: http://demonstrations.wolfram.com/preview.html?draft/93373/000008/ElectronConductanceModelUsingMaximalEntropyRandomWalk Here are more formal derivations: http://arxiv.org/abs/0710.3861 Here is a trial to expand this similarity to quantum mechanics: http://arxiv.org/abs/0910.2724 I'm currently working on my PhD thesis in physics on this subject and so I would really gladly discuss about it.
  24. Basically this classical-quantum correspondence we were talking about is the region of so called quantum chaos - I believe MERW-based model is what they were missing to understand it - in this presentation are for example its 2 intuitive derivations and connection with quantum chaos. If someone is interested, here has developed discussion about MERW: http://www.sciforums.com/forumdisplay.php?f=33
  25. But Heisenberg's quantum uncertainty also doesn't mean that there is no internal dynamics - it only restricts practical aspect: measurement. Taking further implications based on Bell's inequalities assumes that probabilistic models on local deterministic Lagrangian (field) mechanics should be also local - such assumption about models representing our knowledge is just wrong (see maximal entropy random walk). In not standard: idealistic, but practical classical mechanics we also have to have in mind that we cannot have infinite measurement precision, full information - we have to work on probability clouds ... what through chaos, ergodicity leads to practical picture far from the idealistic one ...
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