Why against Stern-Gerlach experiment photons are said to be spin 1?
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From: Igor on 25 Nov 2009 12:05 On Nov 24, 6:05 pm, BURT <macromi...(a)yahoo.com> wrote: > On Nov 24, 1:15 pm, Igor <thoov...(a)excite.com> wrote: > > > > > On Nov 24, 3:43 am, "Y.Porat" <y.y.po...(a)gmail.com> wrote: > > > > On Nov 23, 5:03 pm, Igor <thoov...(a)excite.com> wrote: > > > > > On Nov 19, 4:30 pm, Jarek Duda <duda...(a)gmail.com> wrote: > > > > > > > I never said it was. I said you needed both in order to have a > > > > > > magnetic dipole moment. > > > > > > So what about neutrino? > > > > > According to the Standard Model, the neutrino is a fundamental > > > > chargeless particle, so it should not have a magnetic dipole moment.. > > > > If it ever was discovered that the neutrino has a finite magnetic > > > > dipole moment, it would be back to the drawing board. > > > > ------------- > > > and you Igor forgot to tell us > > > that a very long time > > > > the neutrino was considered massless (as your brain) > > > but only much later the glassless -- > > > > became massive!! > > > > the fact that some mass is hard to detect > > > doe snot mean it doe snot exist > > > it is just out fault not to be able to find it > > > but there is a new golden rule in physics > > > that should be a light tower: > > > > NO MASS - NO REAL PHYSICS !! > > > one day > > > even a block head like you will get it > > > (or may be even discover it himself ?? (:-) > > > and only while it wil be discovered by a dumb mathematician like you > > > (only you !!).. only then > > > you will come out trumpeting it out (:-) > > > > Y.Porat > > > ------------------------------------------- > > > I think all that doe snot is clogging up the logical receptors in your > > brain.- Hide quoted text - > > > - Show quoted text - > > Spin is a mistake. Rotation is more appropriate usage. Spin is when > rotation speed changes sizes. > The skater pulling in her arms. Spin is in the aether as this. > > Mitch Raemsch You are the master of nonsensical jibberish.
From: Igor on 25 Nov 2009 12:15 On Nov 24, 8:12 pm, cjcountess <cjcount...(a)yahoo.com> wrote: > Igor > > You speak to fast, look at the evidence. > > Planck discovered E=hf, for photons > > Einstein discovered E=mc^2, for electrons / matter > > deBroglie discovered E=hf=mc^2, at level of electron, which has -1 > charge and that electron is also a wave. This indicates a smooth > transition from energy to matter, along the same EM spectrum, which > can also be considered the energy/matter spectrum, as well as the > electromagnetic spectrum. You're good to here, providing you actually understand what you've just said. I have my doubts. > Bohr discovered that wavelength of electron is equal to circumference > of circle, with an angular momentum of a multiple integer of h/2pi. This was an ad hoc model for the hydrogen atom which was superseded by Schroedinger's wave mechanics and Heisenberg's matrix mechanics, which essentially form the basis for modern quantum theory. No one uses the Bohr model anymore. > Therefore it follows from this and geometrical evidence that I > presented that, (E=mc^2) = (E=mc^circled) and c = (sqrt -1) Circled? This is a joke, right? > So yes, accelerate a photon, like letting it fall into a strong enough > gravity well, and it should gain enough energy to attain rest mass, > and yes -1 charge. And all this time, people have been seriously searching for where mass comes from. So it's not the Higgs. It's a photon falling through a gravity well. That's just too stupid for words. Learn some simple basic physics. You might want to start with conservations laws. > We already know that photons gain energy and higher frequency as they > inter a gravity field. I am suggesting that, if this gravity field is > strong enough, it will produce electrons from those photons. That's called the gravitational Doppler effect. And unlike your ridiculous idea, it doesn't violate conservation laws.
From: Igor on 25 Nov 2009 12:24 On Nov 24, 5:02 pm, Jarek Duda <duda...(a)gmail.com> wrote: > On Nov 24, 10:09 pm, Igor <thoov...(a)excite.com> wrote: > > > On Nov 23, 10:16 am, Jarek Duda <duda...(a)gmail.com> wrote: > > > > > According to the Standard Model, the neutrino is a fundamental > > > > chargeless particle, so it should not have a magnetic dipole moment.. > > > > If it ever was discovered that the neutrino has a finite magnetic > > > > dipole moment, it would be back to the drawing board. > > > > I've looked at a few papers and they were rather saying something > > > different...http://arxiv.org/abs/hep-ph/0601113 > > > If you notice, that paper doesn't actually say that the neutrino has a > > magnetic moment. It only provides a theoretical upper bound based on > > the most current observations. It's a lot like similar papers on the > > upper limit on photon mass. > > What do You mean? In the paper I've linked there are both upper and > lower bounds ... Yeah, you're correct on that one. Apparently, after re-reading this paper, I see that it's based not on the conventional Standard Model, but on some sort of extended version of it. That's what I meant when I said "it would be back to the drawing board", since the conventional SM doesn't predict a magnetic moment for the neutrino. People are already anticipating new directions in which to take the SM and this paper is a good example.
From: Jarek Duda on 25 Nov 2009 13:21 On Nov 25, 6:24 pm, Igor <thoov...(a)excite.com> wrote: > Yeah, you're correct on that one. Apparently, after re-reading this > paper, I see that it's based not on the conventional Standard Model, > but on some sort of extended version of it. That's what I meant when > I said "it would be back to the drawing board", since the conventional > SM doesn't predict a magnetic moment for the neutrino. People are > already anticipating new directions in which to take the SM and this > paper is a good example. Current theories are usually made that we observe new phenomena and so we add new corresponding terms to the Lagrangian ... For example I have a hypothetic question: can we be sure that electron isn't extremely weak monopole and the same with proton, but with opposite sing? So that it would sum up to zero for uncharged matter and in the other case would be drown out by the charge... If such monopole would be small enough, we shouldn't observe it (yet?) ... but can we really be sure that it's not true? On Nov 25, 2:54 pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) wrote: > The word "spin" in quantum mechanics is misleading. There are no little > balls spinning on an axis. What is called "spin" is quantized angular > momentum, that is, a property of the particle that has units of angular > momentum and is conserved in reactions. Electrons and neutrinos have > units of +/- 1/2 hbar, photons have units of +/- hbar. Ok - with spin there can come angular momentum ... But angular momentum doesn't necessarily have to come with spin - for example traveling twist-like waves behind marine propeller carries angular momentum but aren't topological singularities - doesn't have spin. Possibility of caring angular momentum is kind of natural for waves ... while behavior of quantum phase around nonzero spin particle suggest that it corresponds to its internal magnetic structure, which photon doesn't have. We have no doubt that photons can carry angular momentum, but it doesn't imply that they have to carry spin. And I still haven't seen any argument that they really have also spin ...
From: Darwin123 on 25 Nov 2009 20:03
On Nov 24, 2:27 am, Jarek Duda <duda...(a)gmail.com> wrote: > Darwin, thanks You for the answers, but still ... > Magnetic field can be created by 'going around' or 'spinning' charges > but neutrino is believed to have magnetic moment, but it clearly > doesn't apply to these categories.http://arxiv.org/abs/hep-ph/0601113 > The simplest/lightest fermion - neutrino is kind of 'pure spin', but > we have no such 'pure charge' particle - electron is much heavier and > requires also spin. > That suggest that maybe it's not charge what is fundamental, but > rather spin ... and neutrino suggest that this spin goes with > (extremely weak) magnetic field - it's third, separate way. > > What is spin? In quantum mechanics, spin is the angular momentum associated with polarization. A photon has a spin which is the angular momentum associated with circularly polarized light. An electron has a type of circular polarization, too. Electrons can be described by a fermion field wave, just as light can be described by a boson field wave. However, I predict you won't like this "all wave" picture of spin. You really don't want to picture a wave as a circulating anything. Even the water waves that you speak about are comprised of spinning packets of water. However, you will insist on thinking about the electron as a round ball. Even here, I think I can oblige you.I present the all particle picture of fermion spin. There is an explanation in a semiclassical approximation of quantum mechanics called stochastic electrodynamics (SED). I know SED can't be 100% accurate. It doesn't reproduce the results of quantum electrodynamics in the case of three or more photons. However, I think a picture in SED is about as close to an intuitive picture as one is likely to offer you. In the SED approximation of quantum mechanics, the universe is filled with a background of zero point radiation that is Lorentz invariant. Electrons are pictures as tiny objects with electric charge, very much like the ball model in the Lorentz theory of the electron. The Planck's constant is a multiplicative constant in the spectrum of the Lorentz invariant radiation background. The relative phase between different modes of this background radiation are random. All interactions in this model are classical in the sense of not involving wave-particle duality. One uses the dynamics of special relativity, with orces that are Lorentz invariant. There is that strange feature in SED that the total energy density at every point is infinite. However, the calculations are performed using generalized forces. Most features of quantum mechanics can be reproduced by this model. In the case of a Coulomb potential, one gets stable energy states with a very close correspondance to the hydrogen atom. The zero point radiation just keeps kicking the electron up and down. The statistical behavior is basically hydrogenic. A generalization can be made to all harmonic oscillating systems. One feature that is reproduced is the spin. If you imagine an electrically charged ball being kicked around by the "classical" zero point field, you will see that it has an minimum "spin" that averages to a nonzero value. So in this approximate model, the spin really is a classical spin. What keeps the electron "spinning" is the zero point radiation field. It is angular momentum > I see there is large confusion of it with angular momentum. By definition, it is angular momentum. Calculations using a balance of angular momentum have to include the spin of the electron and the spin of the atom. I think by angular momentum you are talking about Orbital angular momentum. Orbital angular momentum is well known quantity for electrons. The orbitals in a hydrogen atom have an orbital angular momentum designated by the quantum numbers l and m. Less known to most people is the orbital angular momentum of photons. Yes, photons can have an orbital angular momentum even though they don't travel in elliptical orbits. > Quantum rotation operator says that spin means that quantum phase > makes topological singularity of 'spin' degree around spin axis, like > in this demonstrationhttp://demonstrations.wolfram.com/SeparationOfTopologicalSingularities/ > Property of waves to carry angular momentum is something different - > it makes it twist-like traveling wave. The two models are not very different. You can think of an electron as being a twist-like traveling wave. The difference between an electromagnetic wave and an electron wave has more to do with the way polarization vectors add up. In quantum mechanics, there is a wave -particle duality. Therefore, one can explain spin in trms of either waves or particles. However, either description has to be separately self consistent. > For example tornado/swirl carries angular momentum, but doesn't need > topological singularity - it's just rotation around the center. My intuition suggests to me that the low pressure zone of a cyclonic disturbance is analogous to a topological singularity. I strongly suspect that the topological singularity is the limiting case of a "low pressure" zone. The low pressure zone is what keeps the tornado together. If there was no low pressure zone, the tornado would disperse due to centrifugal force. Uhh, I don't like what I just said, so let me rephrase. If there was no low pressure zone, the tornado would disperse due to the absence of a centripetal force. The topological singularity creates the "suction" that keeps the electron together. Not only would an electron disperse due to the absense of centripetal force, it would disperse due to electrostatic repulsion. I don't think these super mathematical descriptions of subatomic particles are completely different from the more conventional description of macroscopic system. Topology applies to weather just as much as it applies to fundamental particles. |