Fermilabs Tevatron particle accelerator has found a mysterious asymmetry in high energy collisions that produce pairs of top and anti-top quark. It seems that the at high energies there is a preference for which direction the top quark quark is produced travelling towards. The standard model predicts no or little such asymmetry, if the result continues to be confirmed, new physics and possibly new particle will be required to explain it. The measurement has a been around for over a year, having already grown from a 2.6 sigma signal a year ago to a 4 sigma signal in June 2011. Physicists normally like to have a 5 sigma signal to confirm a result, unfortunately the Tevatron is at the end of its life, and since the LHC collides proton against protons, and not protons against anti-protons, it will be difficult to get more data to confirm the result.
This hasn't stopped a large crop of papers looking to explain the result with new physics as summarised in ArXiv:1107.0841. A recent model I was particular fascinated by is one where the asymmetry is caused by an axigluon, as described most recently by Tavares and Schmaltz. Gluons are the gauge boson holding quarks together and normally act vectorially, identically to left and right handed particles, however a axigluon that acts exactly oppositely on left and right handed particles is also possible. To explain the top anti-top forward backward asymmetry an octet of axigluons with mass of around 450 GeV is introduced. They then also required doubling the number of quark, adding vector like pairs of quarks, that then decay rapidly by axigluon exchange. Their model contains exactly the extra quarks, I introduced to cancel the anomalies in adding a neutrino interacting axi-photon to the standard model, and in fact looks similar to the E6 model I described below. A axigluon explanation of the top and anti-top asymmetry, would be then very supporting of axial force theory, which is perhaps why I've biasedly am attracted to it. The LHC should however soon be able to confirm or disprove such an axigluon model. So time will tell.
Friday, 15 July 2011
Sunday, 12 June 2011
Symmetry Breaking, Groups E8 and E6
Reviewing articles at ArVix its come to my attention, that most popular super-symmetry and String phenomenologist aren't choosing the right models of symmetry breaking, ignoring classic papers, and proofs, just so they can use too easy but wrong models to fit Higgs bosons into a grand unified theory of the universe. In particle physics a phenomenologist is a physicist that tries to make the bridge between mathematical elegant models produced by theorists, and the experimental results. Because theories like super-symmetry and super-gravity are so remote from practical energy scales and can produce so many different result depend upon how our universe has broken these symmetries, phenomenology is very difficult subject, but it is perhaps the most important, it is where theory lives or dies depending on weather it describe a universe looking like our universe.
The most popular models start with string theory or supergravity which only allows certain mathematical groups to produce self consistent theories. In particular group E8 * E8, is often the starting point. This leads to two copies of matter in the universe so presumably mirror matter should be a favourite model of the missing matter in the universe. In fact mirror matter is only relatively vary investigated though it still looks very consistent with the DAMA and Cogent observations. E8 is particularly nice because choosing it automatically gives the three generations of quarks and leptons share the same forces, as observed, and describe by the standard model. E8 also is the biggest finite lie alegebra (248 roots), and self adjoint, meaning it contains both the groups needed to represent particles and forces in the same represention. That makes is automatically super-symmetric, you get 248 spin-1 force carriers and 248 spin-1/2 particles, see Steven L. Adlers classic paper: . What you don't get is any scalar bosons, so your Higgs particles have to be composites condensing out of the particles that are attracted to themselves with such strength that the lowest energy state of the vacuum contains a sea of these particles. Breaking E8 to three generations of a smaller group E6.
Now E6 has 27 particles its fundamental representation, and when you ask how it breaks symmetry by vacuum condensing, the computation been done and its either $E6 -> F4 * U(1) $ but with every force carrier picking up a mass (clearly not our universe), or $E6 -> SU(2) * SU(6), 27 -> 15 + 12$. The vacuum condensation is complicated enough that it was to be done in simulation by a computer, but the result stands. And do phenomenologists use it? no they don't, again and again they break E6, to SO(10)*U(1), and them have Higgs bosons, (doublets) in the group. Somehow they of they own choice have added scalar multiplets to the models that isn't suppose to have scalars in it, and further, have choosen SO(10) just because its a favourite GUT model, (not one that works, as it predicts faster proton decay than could be real without it have been measured by now. In fact SO(10) is a left-right symmetry theory, while E8 is left-right symmetric and E6 is chiral (chooses a particular direction), so when phenomenologists use E6->SO(10), have broken parity, unbroken it, and rebroken it at second time along there trail. This seem to happen because they of course start with a popular model and see what happens down the trail to low-energy, forgetting what made the popular model, popular in the first place.
To my mind, and using a axial-force, E8, contains U(2) left , U(2) right which will eventually break to U(1)_em, U(1)_axial, SU(2)_left weak force, SU(2)_right, breaking at the same time as 3 seperate generations of particles has formed., then E6 has SU(3) color, U(1)_axial, U(1)_em and SU(2)_left weak force in its SU(6), leaving a SU(2) grouping splitting E6 into the 15 known particles of the standard model grouped into left handed and right handed E6 multiples, and 12 extra quarks grouped into particle and anti-particles multiplets. All the anomalies of U(1)_em and U(1)_axial cancel in this representation, which I wouldn't have found, if I wasn't so keen on having a U(1) axial force. The extra vector-like quarks (i've called terra quarks, borrowing the name from different model by Gamor), then need to gain extra mass, and may form a left-right symmetry breaking condensate reacting with the generation permuting right handed neutrinos that appear when breaking E8 to E6. We have a rather complex vacuum condensate, which will need computational analysis, instead of a standard model Higgs, so phenomological prediction won't be easy from this model, but it does follow the spirit of E8 down to low energy, and doesn't introduce ad hoc scalars, but compute scalar condensates them from first principles. I'm blogging to try and promote this model to someone with the time to compute it.
The most popular models start with string theory or supergravity which only allows certain mathematical groups to produce self consistent theories. In particular group E8 * E8, is often the starting point. This leads to two copies of matter in the universe so presumably mirror matter should be a favourite model of the missing matter in the universe. In fact mirror matter is only relatively vary investigated though it still looks very consistent with the DAMA and Cogent observations. E8 is particularly nice because choosing it automatically gives the three generations of quarks and leptons share the same forces, as observed, and describe by the standard model. E8 also is the biggest finite lie alegebra (248 roots), and self adjoint, meaning it contains both the groups needed to represent particles and forces in the same represention. That makes is automatically super-symmetric, you get 248 spin-1 force carriers and 248 spin-1/2 particles, see Steven L. Adlers classic paper: . What you don't get is any scalar bosons, so your Higgs particles have to be composites condensing out of the particles that are attracted to themselves with such strength that the lowest energy state of the vacuum contains a sea of these particles. Breaking E8 to three generations of a smaller group E6.
Now E6 has 27 particles its fundamental representation, and when you ask how it breaks symmetry by vacuum condensing, the computation been done and its either $E6 -> F4 * U(1) $ but with every force carrier picking up a mass (clearly not our universe), or $E6 -> SU(2) * SU(6), 27 -> 15 + 12$. The vacuum condensation is complicated enough that it was to be done in simulation by a computer, but the result stands. And do phenomenologists use it? no they don't, again and again they break E6, to SO(10)*U(1), and them have Higgs bosons, (doublets) in the group. Somehow they of they own choice have added scalar multiplets to the models that isn't suppose to have scalars in it, and further, have choosen SO(10) just because its a favourite GUT model, (not one that works, as it predicts faster proton decay than could be real without it have been measured by now. In fact SO(10) is a left-right symmetry theory, while E8 is left-right symmetric and E6 is chiral (chooses a particular direction), so when phenomenologists use E6->SO(10), have broken parity, unbroken it, and rebroken it at second time along there trail. This seem to happen because they of course start with a popular model and see what happens down the trail to low-energy, forgetting what made the popular model, popular in the first place.
To my mind, and using a axial-force, E8, contains U(2) left , U(2) right which will eventually break to U(1)_em, U(1)_axial, SU(2)_left weak force, SU(2)_right, breaking at the same time as 3 seperate generations of particles has formed., then E6 has SU(3) color, U(1)_axial, U(1)_em and SU(2)_left weak force in its SU(6), leaving a SU(2) grouping splitting E6 into the 15 known particles of the standard model grouped into left handed and right handed E6 multiples, and 12 extra quarks grouped into particle and anti-particles multiplets. All the anomalies of U(1)_em and U(1)_axial cancel in this representation, which I wouldn't have found, if I wasn't so keen on having a U(1) axial force. The extra vector-like quarks (i've called terra quarks, borrowing the name from different model by Gamor), then need to gain extra mass, and may form a left-right symmetry breaking condensate reacting with the generation permuting right handed neutrinos that appear when breaking E8 to E6. We have a rather complex vacuum condensate, which will need computational analysis, instead of a standard model Higgs, so phenomological prediction won't be easy from this model, but it does follow the spirit of E8 down to low energy, and doesn't introduce ad hoc scalars, but compute scalar condensates them from first principles. I'm blogging to try and promote this model to someone with the time to compute it.
Tuesday, 7 June 2011
Neutron Scattering and Fifth Forces
I regularly read ArXiv for reports on the experimental limits on Fifth Forces. But this on I missed up to now. Neutron Scattering is regularly performed on every material under the sun, and in neutron scattering, scientist clearly see point like scattering from the strong force of a nucleus, giving very clear scattering from a collation of femtoscopic points. What scatterers don't see is any scattering from long range $1/r^2$ type columb forces. This clearly limits strongly any fifth force felt by neutrons. Unfortunately the one paper producing limits on fifth forces from neutron scattering is the R. Barbieri and T.E.O. 1975, and they start there calculation from a parameterised best fit to scattering from a Russian experiment done in 1966. Another words, the experiment hasn't been done with a good level of statistical checking. However thinking about its very clear that a massless force with strength 100-1000 time weaker than the electromagnetic force is clearly and obviously excluded by neutron scattering experiments, it would stand out like a sore thumb.
Where does this level fifth forces in general, and in particular our axial force. First B-L forces which act between all known particles are clearly excluded, saying goodbye to B-L chameleon force. In describing our axial force we could not see any way to pin down the particular charges on a proton or neutron, and w guessed at +1/2 for a proton and -1/2 for a neutron as that would be symmetrical and prevent proton decay. However we cannot rule out a charge on 0 on a neutron and 1 on a proton. Thus our axial force remains viable with these charges, we still have requirement that some light charged scalar or vector fields (mass around a few eV) exists to prevent Fermi energy from becoming too great. With both light scalars and neutrinos as light charged fermions under a fifth force, chameleon like behaviour should screen any axial force down to the nanometer scale, guaranteeing that it would not have been observed in existing experiments.
Where does this level fifth forces in general, and in particular our axial force. First B-L forces which act between all known particles are clearly excluded, saying goodbye to B-L chameleon force. In describing our axial force we could not see any way to pin down the particular charges on a proton or neutron, and w guessed at +1/2 for a proton and -1/2 for a neutron as that would be symmetrical and prevent proton decay. However we cannot rule out a charge on 0 on a neutron and 1 on a proton. Thus our axial force remains viable with these charges, we still have requirement that some light charged scalar or vector fields (mass around a few eV) exists to prevent Fermi energy from becoming too great. With both light scalars and neutrinos as light charged fermions under a fifth force, chameleon like behaviour should screen any axial force down to the nanometer scale, guaranteeing that it would not have been observed in existing experiments.
Thursday, 19 May 2011
Vectrinos, the Solar Corona, and the Neutrino Sea
In my previous post, I discuss the Fermi Energy needed to allow enough neutrinos to
live inside ordinary substances, in order to balance out the effects of an axial force. Its clear, the values are just to high to be practically possible. This doesn't yet rule out the axial force, provided a scalar or vector particle with mass in the region 10meV to 1eV, exists, such a particle, would not be subject to Fermi repulsion, and could be present in whatever quantities needed to balance out the axial charges on nucleons. Scalar or Vector neutrino (normally scalar, but I find theories with fundamental scalars unattractive), are present in super-symmetric theories with unknown masses. So a super-symmetric theory might allow an axial force.
Such a particle would also help with another problem the axial force faces, Radiation
from the Sun and Stars. The hot gases in star is in thermodynamic equilibrium and as such we expect all degrees of freedom to have equal energy. Thus we would expect the Sun to radiate an equal amount of photons and axi-photons. The axi-photons would be absorbed in the Earth atmosphere, and we'd observe a Sun burning half as brightly as expected. Astronomers current calculations describe the brightness of the Sun up to a few percent either way, so a Sun radiating equal amounts of axi-photons is not credible.
Let us investigate a super-symmetric vector (spin-1) analog of a neutrino, also with +1 or -1 axial charge, with a mass in the 1 eV region ( 1eV ~13000 Kelvin). We'll call it a Vectrino. Vectrinos are more interesting to us, than sneutrinos because, an
axi-photon can easierly pair produce Vectrinos, spin 1 -> spin 1 + spin 1. Remember this is in three dimension of spin, the extra spin on the RHS of the equation, can occur if the Vectrino, anti-Vectrino pair is emitted near 45 degrees to the incoming axi-photon. The Vectrinos can further scatter producing more axi-photons. The result is that Vectrinos lead to a region, absorbing all the axi-photon and other axial energy converting it in to a region as dense in Vectrinos as pressure will allow. It will act as an opaque thermal conduction barrier, allow only standard light through.
This wouldn't happen with scalar neutrinos, where the spin 1 -> spin 0 + spin 0, is impossible, and pair production is strongly suppressed.
Our Vectrino dense region would occur in the suns chromosphere, absorbing up coming energy in a region containing little hydrogen. At the top of the chromosphere high temperature protons, attracted by the axially negative region, would supply the pressure necessary to keep the Vectrinos compressed and in place. Light would cross the region normally and find a lot few protons in the corona to be shared between. Thus we have a new explanation of solar coronal heating, which has needed one of a while, see this paper.
Our original paper, used right handed neutrinos with a mass of a around 30eV, to preform the same trick of stabilising matter against Fermi pressure, and heating the
solar corona. However I do not now believe such massive particles could exists without there decay energy, showing up, in for instance the boiling of water. Scalar or Vector particles on the other hand, would cap the Fermi energy at just below there mass. The balance of Fermi-energy, axial binding energy, and scalar mass energy, would be hidden in lab experiments.
We have saved the axial force, at the expense of adding a usually new particle. The particle belong to super-symmetry, but an unusually form of super-symmetry, and the axial force was already unknown to physics. Scientifically, our belief in the axial force must reduce accordingly. It would help if one experiment or observation definitively needed an axial force, but without that the axial force is reduced to the realm of possible but not likely or needed.
live inside ordinary substances, in order to balance out the effects of an axial force. Its clear, the values are just to high to be practically possible. This doesn't yet rule out the axial force, provided a scalar or vector particle with mass in the region 10meV to 1eV, exists, such a particle, would not be subject to Fermi repulsion, and could be present in whatever quantities needed to balance out the axial charges on nucleons. Scalar or Vector neutrino (normally scalar, but I find theories with fundamental scalars unattractive), are present in super-symmetric theories with unknown masses. So a super-symmetric theory might allow an axial force.
Such a particle would also help with another problem the axial force faces, Radiation
from the Sun and Stars. The hot gases in star is in thermodynamic equilibrium and as such we expect all degrees of freedom to have equal energy. Thus we would expect the Sun to radiate an equal amount of photons and axi-photons. The axi-photons would be absorbed in the Earth atmosphere, and we'd observe a Sun burning half as brightly as expected. Astronomers current calculations describe the brightness of the Sun up to a few percent either way, so a Sun radiating equal amounts of axi-photons is not credible.
Let us investigate a super-symmetric vector (spin-1) analog of a neutrino, also with +1 or -1 axial charge, with a mass in the 1 eV region ( 1eV ~13000 Kelvin). We'll call it a Vectrino. Vectrinos are more interesting to us, than sneutrinos because, an
axi-photon can easierly pair produce Vectrinos, spin 1 -> spin 1 + spin 1. Remember this is in three dimension of spin, the extra spin on the RHS of the equation, can occur if the Vectrino, anti-Vectrino pair is emitted near 45 degrees to the incoming axi-photon. The Vectrinos can further scatter producing more axi-photons. The result is that Vectrinos lead to a region, absorbing all the axi-photon and other axial energy converting it in to a region as dense in Vectrinos as pressure will allow. It will act as an opaque thermal conduction barrier, allow only standard light through.
This wouldn't happen with scalar neutrinos, where the spin 1 -> spin 0 + spin 0, is impossible, and pair production is strongly suppressed.
Our Vectrino dense region would occur in the suns chromosphere, absorbing up coming energy in a region containing little hydrogen. At the top of the chromosphere high temperature protons, attracted by the axially negative region, would supply the pressure necessary to keep the Vectrinos compressed and in place. Light would cross the region normally and find a lot few protons in the corona to be shared between. Thus we have a new explanation of solar coronal heating, which has needed one of a while, see this paper.
Our original paper, used right handed neutrinos with a mass of a around 30eV, to preform the same trick of stabilising matter against Fermi pressure, and heating the
solar corona. However I do not now believe such massive particles could exists without there decay energy, showing up, in for instance the boiling of water. Scalar or Vector particles on the other hand, would cap the Fermi energy at just below there mass. The balance of Fermi-energy, axial binding energy, and scalar mass energy, would be hidden in lab experiments.
We have saved the axial force, at the expense of adding a usually new particle. The particle belong to super-symmetry, but an unusually form of super-symmetry, and the axial force was already unknown to physics. Scientifically, our belief in the axial force must reduce accordingly. It would help if one experiment or observation definitively needed an axial force, but without that the axial force is reduced to the realm of possible but not likely or needed.
Wednesday, 18 May 2011
The Axial Force and the neutrino sea.
Regularly readers will know that my blog is many about the possibility of a fifth force, which acts primary between neutrinos. The strength of the force is unknown, but
can be comparatively large and still not noticeable by traditionally experimental because it doesn't interact with electrons at all. The simplest case a long force is a fully conversed charges with a massless force carrier, the axi-photon. I have not yet
investigate the case of massive force carrier, but the massive case would show up to easierly in accelerator experiments for masses ranges 137 MeV (more massive than a Pion) to 100 GeV.
If neutrinos carry this conversed charge so much protons and or neutrons, specifically the charge on the Neutron must equal the charge on a proton plus the charge on a neutrino, so that beta decay can occur. Further since both protons and neutrons can flip the spins easierly. The axial charge on a spin up nucleon is the same as that on a spin down nucleon. This is the opposite to neutrinos where by definition a right handed neutrino or anti-neutrino has the opposite axial charge to the left handed neutrino.
In any material with a axial net charge its nuclei, the axial force will collect a sea of neutrinos in order to the cancel out it the net axial charge. Since neutrinos are light this will effective screen out the axial force, and make it very difficult to observe, hence why the axial force has not yet been observed. However neutrinos are fermions can as such there is a limit to how many can be placed in a given volume of material. I make a terrible error, in my first paper. I used the wrong formule of the Fermi Energy of the neutrino sea, I used the non-relativistic, when formule when most of the neutrinos are clearly travelling near the speed of light.
The correct formula is.
$$E_F = {\h c}/{2} ({3 ρ}/{π} )^{1/3} $$
Thats the Energy of the most energetic neutrino assuming a neutrino number density of ρ The total Energy is just
$$E_T = {3/4}N E_F = {3/4} {ρ}V E_F $$
We don't need to know the strength of the axial force to calculate the Fermi Energy due to neutrinos (we assume 3 kinds as so far known). If the force isn't strong enough to bind neutrinos of the maximum (fermi) energy to the substance, then the substance will be left with an overall charge. This might lead to a detectable long range forces between substances, which might well have been observed already.
In fact the Fermi energy for most substance is rather large, assuming the axial charge is -1/2 on a proton and +1/2 on a neutron. We have.
The total energies are thus just to high to be practicle, some 2.7 Mega Joules in one cubic centimeter of tap water.
In order to save the axial force we need to add either several sterlie neutrinos in the 1eV to 1KeV ranges, or more add scalar sneutrinos in the mass range 0.1 eV to 100eV. Scalar neutrinos would not generate any Fermi Energy at all, and would allow any density of matter. Similar arguments apply for any long ranges force that need to cancelled inside matter. For instance a chameleonic B-L (baryon number minus Lepton number) force,
again needs a light charged scalar particle in order to solve the problem of Fermi-Energy.
can be comparatively large and still not noticeable by traditionally experimental because it doesn't interact with electrons at all. The simplest case a long force is a fully conversed charges with a massless force carrier, the axi-photon. I have not yet
investigate the case of massive force carrier, but the massive case would show up to easierly in accelerator experiments for masses ranges 137 MeV (more massive than a Pion) to 100 GeV.
If neutrinos carry this conversed charge so much protons and or neutrons, specifically the charge on the Neutron must equal the charge on a proton plus the charge on a neutrino, so that beta decay can occur. Further since both protons and neutrons can flip the spins easierly. The axial charge on a spin up nucleon is the same as that on a spin down nucleon. This is the opposite to neutrinos where by definition a right handed neutrino or anti-neutrino has the opposite axial charge to the left handed neutrino.
In any material with a axial net charge its nuclei, the axial force will collect a sea of neutrinos in order to the cancel out it the net axial charge. Since neutrinos are light this will effective screen out the axial force, and make it very difficult to observe, hence why the axial force has not yet been observed. However neutrinos are fermions can as such there is a limit to how many can be placed in a given volume of material. I make a terrible error, in my first paper. I used the wrong formule of the Fermi Energy of the neutrino sea, I used the non-relativistic, when formule when most of the neutrinos are clearly travelling near the speed of light.
The correct formula is.
$$E_F = {\h c}/{2} ({3 ρ}/{π} )^{1/3} $$
Thats the Energy of the most energetic neutrino assuming a neutrino number density of ρ The total Energy is just
$$E_T = {3/4}N E_F = {3/4} {ρ}V E_F $$
We don't need to know the strength of the axial force to calculate the Fermi Energy due to neutrinos (we assume 3 kinds as so far known). If the force isn't strong enough to bind neutrinos of the maximum (fermi) energy to the substance, then the substance will be left with an overall charge. This might lead to a detectable long range forces between substances, which might well have been observed already.
In fact the Fermi energy for most substance is rather large, assuming the axial charge is -1/2 on a proton and +1/2 on a neutron. We have.
| Material | Neutrino Density $cm^{-3}$ | Fermi Energy |
|---|---|---|
| Day Air | $1 * 10^{13} $ | 1.9 eV |
| Water | $3.34 * 10^{22} $ | 1.3 KeV |
| Uranium-238 | $3.5 * 10^{24}$ | 4.68 KeV |
| Bismith | $1.78 * 10^{24} $ | 3.5 KeV |
| NaCl (Salt) | $2.7 * 10^{22} $ | 1.27 KeV |
| Pyrex Glass | $ 1.16 *10^{21} $ | 0.4 KeV |
| Palladium | $4.89* 10^{23} $ | 3.3 KeV |
| Copper | $ 2.34* 10^{23} $ | 2.6 KeV |
| Zinc | $ 1.76 * 10^{23} $ | 2.4 KeV |
| Barium Chloride | $ 2.9*10^{23} $ | 2.24 KeV |
The total energies are thus just to high to be practicle, some 2.7 Mega Joules in one cubic centimeter of tap water.
In order to save the axial force we need to add either several sterlie neutrinos in the 1eV to 1KeV ranges, or more add scalar sneutrinos in the mass range 0.1 eV to 100eV. Scalar neutrinos would not generate any Fermi Energy at all, and would allow any density of matter. Similar arguments apply for any long ranges force that need to cancelled inside matter. For instance a chameleonic B-L (baryon number minus Lepton number) force,
again needs a light charged scalar particle in order to solve the problem of Fermi-Energy.
Wednesday, 14 July 2010
Further Solar Neutrino Mysteries
Scientists have known how the Sun shines for quite a while, thermonuclear fusion was well established as was the so called proton proton chain, in which four protons, from hydrogen atoms are converted into Helium nuclei,2 neutrinos and two positrons. Since neutrinos react rarely enough to mostly pass through all the sun, it would be possible to measure the rate of thermonuclear fusion in the sun, by how many neutrino where captured in a lab on earth. Yet when the homestake experiment first measured the number of neutrinos they found only third of the amount expected. Later experiments confirmed this, and it turned out that neutrinos could change the flavour, or type of neutrino from ones with react with atoms, to one which can't. While the sun create only electron type anti neutrinos, by the time the react with an detector on earth, they become an equal mix of electron, muon and tau anti-neutrinos. Since only the electron type reacts with atoms, the rate observed is just one third of the amount predicted by the sun being powered by fusion. Mystery solved and everything ok again, except...
Just published on ArXiv, C.R. Das and J. Pulido find a much better fit to measurements amount of neutrinos coming from the sun, if as well as oscillating, some of them also decay. The paper is a possible indication of non standard interactions.
I can't help but relate this to my own, axial force theory. It something of an oversight but so far, I've only done the briefest of calculation of cross-sections for high-speed neutrino, due to the axial force, noting that effect falls over as 1/E^2 for ultra relativistic neutrino we can detect from the sun, any effect would be small. However, extra scattering it is at least of the right sign, to remove some of the extra electron neutrinos. In addition the axial force can allow neutrinos to decay from one form to another (but only in the presence of other matter), to some degree. So plenty of calculations for me to do.
Monday, 14 June 2010
Minos points to neutrinos breaking CPT
One of the most fundamental theorems in quantum field theory, is the CPT theorem, it relates the properties of matter and anti-matter particles, and in particular shows that anti-particles must have the same mass and lifetime as ordinary particles. A recent measurement from MINOS, a accelerator neutrino experiment, has for the first time offered evidence that CPT is broken, it measured the mass difference between electron and muon neutrinos and also electron and muon anti-neutrinos, by watching them oscillate, changing form, in the 735Km between the Fermilab where the neutrinos are created and MINOS neutrino detector.
The first measurement show that the mass difference between electron and muon neutrinos is 40% smaller than for anti-neutrinos. The experimental uncertainty leaves just a 5% chance that the mass difference is the same for both particles. Unless some other effect such as interaction with the background matter along the journey has prevented some of the muon neutrinos oscillating to electron neutrinos, it looks like evidence of CPT violation for the first time. CPT violation also applies violation of Lorentz symmetry, so the effect would be in some way breaking specially relativity. I expect that this measurement may disappear as more data come in, but note that my Axial-force would imply that ordinary matter has a background sea of neutrinos that might interact with the travelling neutrinos (more so that anti-neutrinos), to slow the neutrino oscillation.
The first measurement show that the mass difference between electron and muon neutrinos is 40% smaller than for anti-neutrinos. The experimental uncertainty leaves just a 5% chance that the mass difference is the same for both particles. Unless some other effect such as interaction with the background matter along the journey has prevented some of the muon neutrinos oscillating to electron neutrinos, it looks like evidence of CPT violation for the first time. CPT violation also applies violation of Lorentz symmetry, so the effect would be in some way breaking specially relativity. I expect that this measurement may disappear as more data come in, but note that my Axial-force would imply that ordinary matter has a background sea of neutrinos that might interact with the travelling neutrinos (more so that anti-neutrinos), to slow the neutrino oscillation.
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