Why 1/3 ?
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From: Rock Brentwood on 17 Jun 2010 19:48 On Jun 6, 8:48 am, "OG" <o...(a)gwynnefamily.org.uk> wrote: > Is there an inherent explanation within the standard model for the of the > charge on quarks to be (plus/minus) 1/3 or 2/3 that of the charge on the > lepton? Actually, yes. There's a self-consistency condition on the spectrum of charges. In order to fit consistently with the SU(2) and SU(3) parts of the standard model, the charges in the U(1) part have to be set a certain way. The consistency condition is that all cubic combinations from SU(2), SU(3) and U(1) for the left-helical modes have to match those for the right-helical modes. If you keep out the right neutrino (or equivalently: set its SU(2) and SU(3) charges to 0, as well as its U(1) charge), then the condition uniquely clamps down on the U(1) part. Otherwise, if the right- neutrino is added in, then there are 2 degrees of freedom in the solution (equivalently: two types of charges consistent with SU(2) and SU(3)). The charge eigenvalues for SU(3) are the "chromaticity" coordinates, conventionally taken as L_3, L_8. Putting these on the x and y axis, then "color space" is the 2-D continuum spanned by these 2 axes. The red, green, blue and cyan, magenta, amber (or customarily: anti-red, anti-green, anti-blue) charges occupy the 6 cardinal points along a hexagon in the L_3, L_8 plane. red + green + blue = 0 = cyan + amber + magenta and cyan = -red, amber = -blue, magenta = -green. (SU(3) has 8 degrees of freedom, but only 2 can be simultaneously diagonalized). The "opposites attract" and "likes repel" rule generalizes. The degree of attraction/repulsion is proportional to the cosine of the angle separating any two charges. So, red-red is 100% repelling, red-cyan 100% attractive, red-amber, red-magenta 50% repelling, red-green, red- blue 50% attractive. The only mutually attractive combinations are red-cyan, green-magenta, blue-amber, red-green-blue, cyan-amber- magenta. The SU(2) part of the spectrum is, by convention, I_3. (SU(2) has 3 degrees of freedom, but only 1 can be diagonalized at a time). It's "isospin" and only exists for the left-helical particles and right- helical anti-particles. The U(1) part of the spectrum is NOT electric charge, but "hypercharge", Y. It is also left/right dependent. The only combination of Y and I_3 which gives long distance interaction is the one that is left/right symmetric. That's the electric charge Q = Y + I_3 (or Y + I_3/2 depending on whose convention you adopt). So, fixing Y also fixes Q. The net result of solving the cubic conditions -- if there is a right neutrino -- is that you have two types of charge. One is Y (which gives you Q), and the other is 1/2 (Baryon - Lepton), which I denote G. If there's a force associated with G, it would have the following properties: (1) ordinary matter would be a HUGE positive source since the neutrons' G charge would be unbalanced. (2) right neutrinos would have negative G and would be attracted to matter, particularly large sources of neutrons, such as galactic cores and neutron stars. In effect, they would congregate as a kind of otherwise-invisible cloud around these large sources of positive G charge and (since they have no SU(2), SU(3) or U(1) charges) they would not interact with matter at all -- other than by gravity -- and the only way you'd even be able to tell they were there or see them is by their gravitational effect. This is in contrast to left-neutrinos, which are quite active (comparatively speaking), by virtue of the non-zero SU(2) charge. (Yes, left-neutrinos are charged, not neutral. Tney're only ELECTRICALLY neutrino, but not SU(2) neutral! Nor even U(1) neutral!)
From: PD on 18 Jun 2010 11:24 On Jun 17, 6:11 pm, franklinhu <frankli...(a)yahoo.com> wrote: > > > Well, first, isospin is a strong force concept. In my model the strong > > > force doesn't exist at all (since everything is just an electrostatic > > > positron/electron force) and neither does isospin. > > > Isospin exists because there are selection rules that restrict > > processes that are not present in electromagnetic interactions, as > > well as symmetries that are not at all obvious in your scheme. The > > fact that these rules exist for neutrons and protons and the > > electromagnetic interaction doesn't account for them AT ALL, is one > > way we know that there is an interaction other than electromagnetic > > that is responsible. > > As I had shown with the lambda, I think it is actually the physical > structure of these particles which controls branching, not just the > electromagnetic force. So give me an example of a selection rule that > I should be able to explain, and I'll see if I can explain it. I've given you places where you can read about selection rules to your heart's content. It will NOT DO for you to just try to call "Pull", have someone offer a selection rule, and to have you attempt to tackle them in an ad-hoc fashion with only qualitative handwaving of the sort "I'd expect it to be smaller" or "I'd expect it to be greater". HOW MUCH smaller or HOW MUCH greater is what is required of a theory. You really bear the responsibility for being aware of all the known experimental data and known selection rules, conservation laws, and quantum numbers -- and then to show that your model can QUANTITATIVELY predict the quantities or ratios observed (or better, yet to be observed). > > > > > > > > Spin, I think is what you measure from Stern-Gerlach setup and I think > > > it would be more accurate to call the property "spot" rather than spin > > > since the 1/2 spin just refers to the fact that the experiment > > > produces 2 spots as opposed to 1 or 3 spots. > > > Again, your horribly weak background encumbers you. Spin has a wide > > variety of experimental implications other than the original Stern > > Gerlach experiment, and it plays a huge role in many aspects of > > particle interactions, including kinematics of decays, branching > > ratios, and so forth. Until you decide that it's time to actually sit > > down and read one of the sources that I recommended to you, you will > > constantly be missing crucial experimental constraints that all models > > must respect. > > > > I believe that this > > > separation is simply due to the proton/electron dipoles lining up with > > > the magnetic field and separating once they enter the field. As such, > > > both neutrons and protons contain a dipole pair and in fact any > > > particle which has unbalanced positive/negative charages will come out > > > to spin 1/2. > > > > > According to you neutrinos and neutrons have common composition. > > > > However, neutrons and neutrinos differ dramatically in terms of their > > > > properties, other than mass. For example, neutrons have baryon number > > > > 1 and neutrinos 0; neutrons participate in the strong interaction and > > > > the electromagnetic interaction and neutrinos do not; unbound neutrons > > > > have a finite lifetime and neutrinos do not; neutrons come in one > > > > variety and neutrinos come in three. > > > > The difference is very subtle. Imagine you have a billiard table which > > > is filled a string balls in the center of the table. Hit a ball onto > > > one end of the balls and this causes a single ball to pop out of the > > > backend of the mass of balls. The energy that gets transfered from one > > > ball to another along a line is a neutrino. In this way, a neutrino is > > > merely an energy wave propagating through a medium. This is why we > > > measure it to have no mass and the speed of light. It is effectively, > > > a specialized photon. > > > No, it is not. The photon is spin 1, the neutrino is spin 1/2. > > Gee, I always wondered how they measure the spin of a particle when > you can hardly detect it at all. :) Then I suggest you satisfy your curiosity by doing some decent background reading. > > Photons > > > obey Bose-Einstein statistics, neutrinos obey Fermi-Dirac statistics. > > The photon participates in the electromagnetic interaction, the > > neutrino does not. The photon can decay into an electron-positron > > pair, the neutrino never does. > > In my model, the photon can kick out a poselectron as an electron/ > positron pair as a massive wave. Since a neutrino is but a single > point wave, it wouldn't have the mechanical energy to do this. At the > very least, it has a much different mechanical interaction. No, you do not understand. Both neutrinos and photons have measurable energy. If a photon has an energy greater than 1.022 MeV, then it can -- and is often observed to -- create an electron-positron pair. A neutrino with any energy greater than 1.022 MeV is NEVER observed to create an electron-positron pair. If you do not know how the energy of particles is measured, then I suggest you do some of the background reading I've recommended. > > The photon is its own antiparticle, the > > > neutrino and antineutrino are distinct and produce different > > interactions. That's for starters. > > Seems to me that there is much research over whether the neutrino is > its own antiparticle - that they are distinct doesn't seem at all > clear. > I think you should check this some more. > > > > Again, your astounding lack of familiarity with background information > > should motivate you to correct that deficiency, and I don't understand > > why you would hesitate to do that. > > Oh, I'd love to spend my days at the university looking this stuff up, > but I got to make a living doing something else and I've got 4 little > kids - it's a wonder I have any time to write to you today! But thanks > for the quick replies. Well, let me put it to you this way. Without this background information, the time that you are spending on it now -- at the expense of your 4 little kids -- is a complete waste of time. You might as well be trying to produce gold via alchemy using your kitchen spice rack. > > > > > > > > Now put a mass of balls into the center of the table. Then, take a > > > ball and drag it through the balls in the center of the table. This > > > greatly disturbs the balls and causes all sorts of collisions which > > > would break down the ball if it kept up long enough. This is a > > > neutron. > > > > The final rub is that energy can be lost by generating these > > > "neutrino" waves but particles can also lose mass and energy by > > > ejecting a poselectron into the aether which is undetectable. I have > > > these noted as a "neutrino" above, but really it would be more > > > accurate to say that these are poselectrons lost to the aether, rather > > > than neutrinos. However, the net result is the same which is to carry > > > energy away from the reaction. > > > > If you have been reading my other posts, I have been arguing that > > > there is actually only 1 type of neutrino which produces 3 types of > > > interactions. In solving the solar neutrino problem, we have pinned > > > the problem on the neutrino, but I would pin the problem on the > > > experiments failing to capture all the neutrinos. > > > No, I don't think you understand the experiments. > > It is clear that are neutrinos that produce products Y and not > > products X, and then by changing a beam configuration you can generate > > neutrinos that produce products X and not products Y. > > This is about as clear an indication that there are different kinds of > > neutrinos you can get. > > We had a discussion about this very point where this is the experiment > I proposed, but this experiment has NEVER been done. If you did so, I > bet you would see that Y neutrinos produce X & Y neutrinos and X > neutrinos produce Y & X neutrinos. No, this is not true. > All of the newest experiments are > showing this and attributing it to neutrino oscillation. No, there is a difference. Neutrino oscillation experiments confirm the *transformation* of neutrinos from one flavor to another over a long baseline. That is, they place identical detectors at two different locations from a neutrino source (or the same detector at different distances from two different sources), and they confirm that the neutrinos produce products X but not Y at one location, and then X and Y at a different location. > > > > > > The only valid > > > neutrino detector is the SNO neutral current detector which detects > > > all the neutrinos (which are identical) from the sun just fine. > > > You really believe that the ONLY valid neutrino experiment is SNO???? > > Valid in the sense that it detects all of the neutrinos as it should. So you say that other experiments are not valid because they don't produce the results you expect from your model? This is called cherry- picking of data and it is scientific fraud. > No solar neutrino deficit problem with SNO. That calculations of > neutrino numbers match up shows this experiment is working as > designed. Other experiments which do not match up (showing deficit) > show that the experimental setup is deficient. > > > Every > > > other type of neutrino detector has a blind spot which skews the > > > results. My model basically demands a single type of neutrino since a > > > wave is a wave which should be of a single type. > > > > > I'm trying to point out to you, Franklin, that you have many more > > > > properties you need to consider other than the net charge.- Hide quoted text - > > > > > - Show quoted text -- Hide quoted text - > > > > > - Show quoted text - > >
From: Tom Roberts on 18 Jun 2010 22:54 franklinhu wrote: >>> Seems to me that there is much research over whether the neutrino is >>> its own antiparticle - that they are distinct doesn't seem at all >>> clear. >> I think you should check this some more. > > http://www.lbl.gov/Science-Articles/Archive/sabl/2006/May/04-neutrinos.html > Checked - neutrinos are being checked for double beta-decay to see if > neutrinos are Majorana particles. Yes, but you don't understand the context. An important aspect of the context is that when pi+ decay, they are observed to decay to mu+ and nu_mu ~99.99% of the time (the remainder decay to e+ nu_e). Moreover, pi+ have spin 0, and mu+ and nu_mu each have spin 1/2, and for this decay both the mu+ and the nu_mu have helicity = +1/2, 100% of the time [#]. The key point is that they are NEVER observed to have helicity = -1/2. [#] They necessarily are emitted in opposite directions in the pi+ rest frame (conservation of momentum), so their helicities must be equal in order to conserve angular momentum. Helicity is the projection of a particle's spin onto its propagation direction. Similarly for pi-, mutatis mutandis, with helicity = -1/2 (never +1/2). Yes, a Majorana neutrino is its own antiparticle, while a Dirac neutrino is not. For neutrinos to be Majorana particles, there must be some aspect of the dynamics that restricts the helicities in pi+/pi- decay to the observed values. This is a strong requirement that is beyond the standard model. Indeed, I don't know of any plausible way to implement such dynamics. Most physicists believe the neutrino is Dirac, with the neutrinos all having helicity +1/2 and the anti-neutrinos all having helicity -1/2. This is the most plausible way to account for the observations, and is how they are represented in the standard model (the leptons of each generation come in a left-handed doublet {e-,nu_e} and a right-handed singlet {e+}, plus anti-particles which necessarily have opposite handedness). Left-handed == helicity > 0; right-handed == helicity < 0. > [... further excessively naive and ignorant discussion] You obviously do not understand the experimental record. Neutrino oscillations are a recent phenomenon (~1990). There are LOTS of older experiments that compute neutrino fluxes from measurements of the pion and muon beams that are used to decay into the neutrinos. They are the basis of the different types of neutrinos. Get a good textbook on high energy physics, or on particle physics, such as Perkins, _Introduction_to_High_Energy_Physics_. Tom Roberts
From: Tom Roberts on 21 Jun 2010 11:04
Tom Roberts wrote: > Yes, a Majorana neutrino is its own antiparticle, while a Dirac neutrino > is not. For neutrinos to be Majorana particles, there must be some > aspect of the dynamics that restricts the helicities in pi+/pi- decay to > the observed values. This is a strong requirement that is beyond the > standard model. Indeed, I don't know of any plausible way to implement > such dynamics. > > Most physicists believe the neutrino is Dirac, with the neutrinos all > having helicity +1/2 and the anti-neutrinos all having helicity -1/2. > This is the most plausible way to account for the observations, and is > how they are represented in the standard model (the leptons of each > generation come in a left-handed doublet {e-,nu_e} and a right-handed > singlet {e+}, plus anti-particles which necessarily have opposite > handedness). > > Left-handed == helicity > 0; right-handed == helicity < 0. Recent results from both MINOS and MiniBooNE cast doubts on neutrinos being Majorana. They see differences at the 3-sigma level between the mixing parameters for neutrinos and anti-neurinos. While this supports the notion tht neutrinos are Dirac particles, it also suggests there is more going on than is contained in the standard model. Tom Roberts |