SECTION IV: INTRODUCTION TO
THE WEAK FORCE
(See also: "Introduction to the Higgs Boson Papers")
(revised Dec., 2012)
JOHN A. GOWAN
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The weak force is responsible for the creation of our matter-only universe during the "Big Bang", apparently via the asymmetric decay of electrically neutral leptoquark-antileptoquark particle pairs. The weak force is also responsible for the creation, transformation, and destruction of single elementary particles - particles that do not exist in matter-antimatter pairs (as seen in radioactivity, fission, single-particle decays and transformations). Single elementary particles created today must be interchangeable with those created during the "Big Bang" (or anywhere/when else) with respect to all conserved parameters - mass, spin, charge, etc. Creating absolutely (globally) invariant single elementary particles at any (local) time or place is the "global/local gauge symmetry" conservation challenge presented to and surmounted by the weak force, requiring (as a response) the elaborate mechanism of the massive Higgs boson and the Intermediate Vector Bosons (IVBs). The great mass of the IVBs recreates the original energy density of the electro-weak unified-force symmetric energy state in which the elementary particle classes (leptons and quarks) were first created, while the Higgs boson scales and selects the appropriate IVBs and unified-force symmetric energy state to deal with the conservation problem at hand (since there are several possibilities). It is the quantization of the Higgs boson and the IVB masses that ensures the invariance of the weak force transformation mechanism, and further to this point, the masses of these bosons are neither affected nor attenuated by the entropic march of our expanding spatio/temporal universe. The weak force charge is "identity" charge, and is carried implicitly by all massive leptons (including leptoquarks and their derivative baryons) and explicitly by neutrinos. "Identity" charge is strictly conserved and combines attributes of lepton "number" and "flavor" charge: each lepton (electron, muon, tau, leptoquark) has its own "identity" charge (and therefore its own neutrino).
Table of Contents:Abstract
Particles and the Spacetime Metric
Links and References
Introduction: The "W" particle and the "IVBs"
Although this is a somewhat technical paper (but without mathematics), there should be much of interest in the mechanism of the "W" particle for the general reader, since in the action of the IVBs, we glimpse the fearful asymmetry of creation.
The first version of this paper was written in April 1983, submitted to two physics journals in 1985 (rejected by both), and submitted to the Archives of Physics on 9 Aug. 2000 (with several subsequent updates). Unlike my other papers which are mainly of theoretical or philosophical interest, this paper is also potentially of significant practical utility, since it treats the reaction pathways of nuclear transformations.
The "W" is one of several "Intermediate Vector Bosons" ("IVBs") of the weak force (see: "The Particle Table"). Bosons are the "field vectors" or force carriers of the four forces. Bosons are particles or "force quanta" produced by charges; there is associated with every charge a boson responsible for the transmission of the actual force associated with the charge. In the quantum mechanical interpretation of modern physics, every force is transmitted by an actual quantized particle. This notion supplants the classical Newtonian idea of "action at a distance" (which even Newton didn't like). The bosons of the electromagnetic force are "photons"; "gravitons" are the bosons of the gravitational force; "gluons" and mesons are the bosons of the (two-level) strong force; and the very strange "IVBs" (W+. W-, Z neutral, and the hypothetical X) are the bosons of the weak force. These weak force bosons are called "Intermediate" because unlike other bosons, they have a large mass, whereas all other bosons are massless. The "W" and "Z" IVBs are about 80-90 times (respectively) more massive than the proton; the hypothetical "X", presumably responsible for proton decay and the creation of matter itself, is thought to be much more massive.
The huge mass of the IVBs immediately tells us they are very strange particles indeed, because they cannot be made out of the usual nuclear material - quarks and gluons. What then is the "stuff" they are composed of? This is not "atomic matter" in the sense we are familiar with, and these are not particles in the sense we are familiar with, either. The IVBs are particles of interaction only - they are metric catalysts, mediators, or "brokers" which allow and facilitate transformations and decays within and between the "families" of elementary particles, the quarks and leptons, which are respectively the constituents of the nucleus and the electron shell of atomic matter. The "W" IVB is a type of "virtual" particle which exists only during the reaction it catalyzes and is otherwise not seen. Like all virtual particles, the "W" IVB is always potentially present but is actually materialized only within the Heisenberg spacetime limit for virtual reality, or if there is enough energy in the IVB's immediate vicinity to momentarily bring it into existence.
Virtual Particles and the Vacuum "Sea"
"Virtual" particles are the creation/discovery of quantum mechanics, P. A. M. Dirac, and Werner Heisenberg. The "vacuum" of spacetime is actually full of photons left over from the "Big Bang" - resulting in the 2.7K "cosmic background radiation". Traveling at velocity "c", photons are "non-local", which means they are effectively everywhere simultaneously. Due to the Heisenberg "Uncertainty Principle", the energy associated with these photons (or with any given point in space), will vary due to "quantum fluctuations" - depending on the time scale one chooses to associate with a specific photon or spacetime location. The shorter the time scale, the more energy one is allowed to associate with a particular photon or spacetime point and its "quantum energy fluctuation". Pick a small enough time interval and you can associate almost any amount of energy with a specific point or photon, energy sufficient to materialize almost any particle you choose (usually a particle-antiparticle pair due to symmetry conservation). This brief time interval is the "Heisenberg Interval" of "virtual" reality. The energy to produce these virtual particles must be borrowed from the "vacuum" surrounding their point of manifestation, and this energy must be paid back to the vacuum before its loss is "noticed" by the "police" - the conservation laws - particularly the conservation of energy. ("Cinderella" is one example of a folk tale involving virtual reality with its time limit. Indeed, almost every aspect of modern physics has an intuitively realized cultural counterpart, whether in art, mythology, religion, or the occult and mystical traditions.)
As we go back in time toward the "Big Bang", the cosmic background radiation (the effective temperature of spacetime) gets hotter and virtual particles become easier to materialize, because there is more energy nearer at hand available to be borrowed - the energy "economy" becomes richer, so borrowing is easier. Eventually the "vacuum" becomes so energy dense and hot that the virtual particles don't have to borrow energy at all, they can exist as "real" particles in their own right because the environment is so "energy rich" it can support or materialize them all the time. It then becomes a question of which and how many particles the environment can materialize.
In our imagination we can see a whole new reality emerging from the energized "vacuum", materializing out of the virtual particle "sea", like ghosts raised from the dead: the lightest particles surface first, always in particle-antiparticle pairs, and as the temperature continues to rise, heavier particles materialize, including particles whose names we do not know because they have not yet been discovered. We know that among this carnival of particles there are at least 6 types of quarks and 6 types of leptons, and that they can transform into one another, not only within "genera" (quark-quark and lepton-lepton) but also (at much higher temperatures) between "genera" (quark-lepton) as well. How do they do it?
If our imaginary spacetime "vacuum" is hot enough (or equivalently, early or young enough relative to the "moment of creation"), we will see the IVB catalysts as well as the particles they help to interact. Transformations will become easier and more common until a temperature and energy density is reached at which the IVBs are materialized. At this point a "phase transition" takes place because the metric itself becomes the IVB - spacetime becomes dense and energetic enough to act as a cosmic-sized IVB and particles transform freely into one another (within certain classes, depending upon temperature). At high energy density particles are so close together they can swap charges and energies without "concern" for the conservation laws, simply due to their extreme closeness and the high temperature and energy density of this very compressed metric. (The lowest energy phase transition occurs at the energy density/temperature of the electroweak force unification era - a symmetric energy state of the early universe reproduced by the large mass of the "W" family of IVBs.) In the electroweak symmetric energy state the separate leptonic "species" (electrons, electron neutrinos, and their heavier kin) are collected into their common "generic" identity ("leptons"), and likewise the quark species gather into their generic identity ("hadrons"). Within each "genus", transformations of "species" identity take place naturally, simply as a matter of course between congeneric members. This is the general principle underlying the IVB transformation mechanism. (See: "The 'W' IVB and the Weak Force Mechanism".)
As the temperature continues to rise, spacetime
goes through several more "phase transitions" which are symmetry
states of successive unifications of the four forces. The "W"
IVB mass "family" is gauged or scaled (by the appropriate Higgs
boson) to the lowest or first in this hierarchy of force
unification symmetry regimes, the electroweak unification energy
level. (See: "
Now in our imagination let us reverse the process and allow the "Big Bang" to proceed normally, expanding and cooling spacetime. Spacetime quickly cools below the point where it can act like a cosmic-sized IVB, and particles can only transform if they get caught in local "knots", eddies, or fluctuations of sufficient metric energetic density. As spacetime continues to expand and cool, all the virtual particle-antiparticle pairs rapidly disappear back beneath the "surface" of the virtual sea, the heaviest ones first and the lightest ones lingering the longest. The IVBs are among the first to go, and as the spacetime metric cools and expands, transformations among or between elementary particles become less frequent because these very heavy metric particles or quantized "knots" of spacetime (the IVBs) are very expensive and hence very difficult to materialize, depending entirely on the temperature and energy density of the local spacetime metric. As spacetime passes through the phase transitions between three successive levels of force unification, a great deal of heat is released reflecting the loss of symmetry (analogously to the "heat of condensation" released by rain or freezing water). This energy contributes to the heat and the formation of particle-antiparticle pairs during the "Big Bang". (The original positive energy of the "Big Bang" may be due to a similar loss of symmetry or "degrees of freedom" as our asymmetric universe of electromagnetic energy (with its special "life-friendly" physical constants) separated from the all-symmetric Multiverse.)
"Real" (temporal) particles are left floating on the "surface" of the spacetime sea as it cools, while the virtual particles "sink beneath the waves". They are all still there in unlimited potential, but are seen only if enough energy can be brought to bear locally to materialize them, to raise them to the surface of the "sea" and give them again a brief "life".
In the Universe today, with the cosmic background radiation (the basal temperature of spacetime) at about 2.7K, the virtual particle sea is rarely seen because the spacetime metric is cold and energy sparse - a necessary condition, however, for our life form. But just occasionally, for very brief instants, due to quantum fluctuations of vacuum energy focused around and by the presence of a real particle, the particles of the "virtual sea" can be raised again to perform their former duties, like the ghostly crew of a briefly surfacing phantom ship. The weak force IVBs are especially difficult to materialize because they are so heavy, hence weak force transformations are rare and for this reason the force is said to be "weak".
I have called the weak force IVBs "metric particles", because I conceive of them as simply quantized "knots" of very dense spacetime metric, whose "mass" is a consequence of the very great energy required to compress (and perhaps convolute) the spacetime metric to such a density and/or configuration. The IVBs simply recreate the very dense metric of the early moments of the Big Bang when all elementary particles were so close together that they could freely swap and exchange charges and energies amongst themselves without danger of violating any charge or energy conservation law - because being so close together (or actually "touching"), exchanges can happen very quickly.
The "W" IVB family specifically recreates the energy-dense metric of the electroweak force-unification era, the moment during the "Big Bang" when the electric and weak forces were united. During this time, quark-quark transformations and lepton-lepton transformations were simply part of the natural course of events - a state of greater symmetry than we know today - a state of "generic" unity/identity rather than specific distinctions - (the mythical analog is a bygone "golden age" or "state of grace" (such as the "Garden of Eden").
Today the role of these metric catalysts, the IVBs, is to bring together within their dense metric a "real" particle ripe for a transformation (typically carrying excess bound energy), and an appropriate particle-antiparticle pair from the virtual "sea", such that the charges of the virtual particle pair can be made available to the real particle, and the energy of the real particle can be made available to the virtual pair, facilitating and effecting the transformation of both.
The most significant feature of the massive IVBs is that they recreate the original conditions of the energy-dense primordial metric in which particles were first created and transformed during the early micro-moments of the "Big Bang". This recapitulation (which is scaled or "gauged" by the Higgs boson) ensures that the original and invariant values of charge, mass, energy, etc. are handed on to the next generation of (single) elementary particles, which must be created exactly the same today as those created during the "Big Bang". The IVB mass not only provides a "conservation containment" where charge and energy transfers can safely take place, it simultaneously ensures that the appropriate alternative charge carriers are present (leptons, neutrinos, mesons). (See: "Identity Charge and the Weak Force".)
There is a crucial difference between the electromagnetic or strong force creation of particles via symmetric particle-antiparticle pair formation, and the weak force creation or transformation of asymmetric "singlet" particles of matter to other elementary forms. ("Singlets" are matter particles without antimatter "mates".) In the case of particle-antiparticle pair creation, there can be no question of the suitability of either partner for a subsequent annihilation reaction which will conserve their original symmetry. Both particles are referenced against each other and gauged or scaled by universal electromagnetic and metric constants such as c, e, and h. However, in the case of the weak force creation or transformation of a "singlet" elementary particle of matter to another form, alternative charge carriers must be used to balance charges, since using actual antiparticles for this purpose can only produce annihilations.
But how can the weak force guarantee that the alternative charge carriers - which may be a meson, a neutrino, or a massive lepton - will have the correct charge in kind and magnitude to conserve symmetry at some future date in some future reaction, or with an unknown partner which is not even its antiparticle? Furthermore, quark charges are both partial and hidden (because they are "confined"), and number charges of the massive leptons and baryons are also hidden (because they are "implicit") - they have no long-range projection (such as the magnetic field of electric charge) to indicate to a potential reaction partner their relative energy state. Nevertheless, conservation of energy, charge, and symmetry require that elementary particles created at any time or place be exactly the same in all respects as those created eons ago in the "Big Bang".
These problems of equilibration are all solved by a return to the original conditions in which these particles and transformations first appeared, much as we return and refer to the Bureau of Standards when we need to re-calibrate our measuring instruments. The necessity for the charge and mass invariance of elementary particles in the service of symmetry and energy conservation therefore offers a plausible explanation for the otherwise enigmatic large masses of the weak force IVBs. Weak force "singlets" can only be referenced against their original creation energy, as scaled by another universal constant of nature, the mass of the Higgs boson. The Higgs and IVB mass serves to recreate the original environmental conditions - metric and energetic, particle and charge - in which the reactions they now mediate first took place, ensuring charge and mass invariance and hence symmetry and energy conservation regardless of the type of alternative elementary charge carrier that may be required, or when and where new elementary particles are created. (See: The Higgs Boson and the Weak Force IVBs.)
No "real" particle is transformed without some compensating transformation in the virtual particle sea. The IVBs act somewhat like a human shaman, spirit-medium, or priest, who connects real people to the spirit world, and in the process transforms both. It is the role of the IVBs to join or bridge the real and virtual worlds of reality, raising virtual particles up to reality and sending real particles down to the virtual "sea". The virtual sea remains connected to temporal reality through a constant exchange between real and virtual particles, a constant potential which becomes actualized in the nuclear transformations and element-building of stars. On Earth it is usually seen only in radioactive decays, nuclear power stations, or in the reactions of cosmic rays and our particle accelerators, or (sadly) in nuclear weapons. Humans are learning to participate, perhaps at their great peril, in exchanges with the Electroweak Era and the "virtual particle sea".
Because the weak force IVBs extract virtual
particles and alternative charge carriers from the universal
vacuum "sea" of spacetime, and these virtual particle charges,
masses, and energies are gauged by global electromagnetic and
metric constants, this common source constitutes another part of
the mechanism which assures that elementary particles created
today will be the same in all respects as those created
yesterday or tomorrow, whether created as "singlets" by the weak
force, or as particle-antiparticle pairs by the electromagnetic
As to why the Z is heavier than the W, I suggest it is because the W, within the symmetric energy state the IVBs create, has only to accommodate the quarks and massive leptons (since only they bear electric charges), but the Z has to account for the neutrinos in addition. Since Z-neutral elastic scattering can occur with all quarks and leptons, the set of particles "under the Z's wing", as it were, is larger than the W's, hence requiring more energy to conjure from the vacuum. There are simply more possibilities for neutral interactions than for charged interactions, and therefore the primordial electroweak unified-force symmetric energy state recreated by the Z is larger and more inclusive (in terms of membership) than that created by the W. Furthermore, since the role of the massive IVBs is expressly to ensure the exact replication of single elementary particles, we may suspect that the neutrino which emerges from a seemingly humble Z-neutral scattering event is not the same "individual" that entered the interaction, even though both are of the same "flavor". This points up the fact that Nature is at considerable pains to protect the integrity and value of the "identity" charge of the neutrinos, requiring a full-on 91 Gev Z-neutral interaction even for an apparently simple scattering event.
In the operation of the "W" family of IVBs, we
see a hint of the process of creation, although not yet creation
itself - because although "W" IVBs are examples of a low-energy
particle-producing interaction between the spacetime metric and
energy, they can produce only alternative charge carriers
(leptons, neutrinos, and mesons) and baryon transformations. "W"
IVBs cannot create or destroy baryons themselves; some
yet-more-energetic analog of this process, perhaps involving
leptoquarks and the superheavy "X" IVB, must hold the key to the
mechanism of the primordial and asymmetric creation of matter,
baryons, and quarks in the "Big Bang". (See: "The Origin of
Matter and Information".) (See: "Table of the
The "identity" charge of the weak force functions in (at least) three crucial ways to conserve symmetry within the context of the material realm of atomic matter. In the first instance, it allows elementary particles to identify their appropriate annihilation partners in a timely fashion (in the case of both "real" and "virtual" particles); in the second instance, and perhaps more fundamentally, the "identity" charge is necessary to allow the exact replication of elementary particles, such that (for example), one electron is precisely identical to every other electron ever created. Without the identity charge, there would be no "benchmark" against which to measure one electron against another, especially in those cases (typical of the weak force) in which single electrons are created rather than particle-antiparticle pairs. Finally, the identity charges of neutrinos, which are the "bare" identity charges of their massive leptonic counterparts, provide an alternative identity charge carrier which accomplishes charge conservation even when single massive leptons (rather than particle-antiparticle pairs) are created. Without this charge-conservation service via the alternative pathway of the neutrino, our asymmetric "matter-only" universe could not have broken the perfect symmetry of light and its particle-antiparticle form during the "Big Bang", since without neutrinos, charge conservation could only have been accomplished via antimatter partners (such as electron-positron pairs), resulting in perpetual annihilations reactions. (See: "The Origin of Matter and Information".)
Returning to the IVBs - it is the role of the
weak force to produce single elementary particles but with a
stringent qualification: every elementary particle ever produced
from the beginning of the universe (and onward into its future)
must be exactly the same as its fellows within type (all
electrons must be identical, and likewise the muon and tau). We
have seen that the neutrino has a role to play in this process,
allowing the creation of a single electron (for example) in the
absence of a positron (anti-electron), and in effect certifying
that any newly created electron is the genuine article in all
respects. But the actual mechanism of manufacture involves the
hugely massive IVBs (81 proton masses) even for the tiny
electron, which weighs about 1/2000 of a proton. Why is this
huge "overkill" of energy during the creation process necessary?
It is because the only way to circumvent the enervating effects
of the entropy of a constantly expanding and cooling universe
upon the manufacture of identical elementary particles over eons
of time is to return to the original primordial energy density
and creative phase of the Big Bang in which these particles were
first formed - every elementary particle forged in the original
mold, as it were. Every weak force transformation involving an
IVB is therefore a recreation of a particular energy density of
the Big Bang, but in miniature. Only by such extreme measures is
the exact similarity of every electron (past, present, and
future) guaranteed, and only these are given the
neutrinos' "certificate of authenticity".
The energy-density recreated by the "W" IVBs is that of the electroweak unification energy density, and all of the leptons and mesons of the "Standard Model" (the alternative charge carriers) can be faithfully reproduced at this energy level. Hence we see the the "alternative charge carriers" (leptons and mesons) occupy a special place both in the functional hierarchy of the cosmos, where they function as catalysts facilitating the creation, destruction, and transformation of single elementary particles, and in the hierarchy of cosmic force-unification energy levels (the electroweak force-unification energy level of the "W" and "Z" IVBs). Baryons cannot be created or destroyed at this energy level, but their quark content can be transformed (via mesons). Creating/destroying the baryons themselves requires the next higher energy level of the "Grand Unified Theory" and the supermassive "X" IVB (unifying the electroweak and strong forces and allowing lepton-quark transformations). The force-unification levels themselves demarcate specific energy-densities at which elementary particles of various kinds can be created or destroyed: 1) leptons/mesons at the electroweak (EW) energy level; 2) baryons/hyperons at the "Grand Unified Theory" (GUT) energy level; 3)leptoquarks at the "Theory of Everything" (TOE) energy level.
One can think of the IVBs as "wormholes" to a younger, hotter universe, connecting our ground-state cold electromagnetic universe with the universe as it existed a few micro-seconds after the "Big Bang". What comes through the "IVB wormhole" is a single elementary particle, newly minted in the original forge and mold of the electroweak era from long ago, and hence identical to every elementary particle (of its type) ever created, or that ever will be created. The "wormhole" connection effectively circumvents the enervating entropy of eons of cosmic expansion that would otherwise make the exact replication of single elementary particles impossible. After a little reflection it becomes obvious that this is the only method which can possibly work reliably. It is this "wormhole" connection between our ground state electromagnetic and the primordial electroweak universe that frees the alternative charge carriers (leptons and mesons), held in the electroweak symmetric energy state, to do (in our ground-state universe) their necessary work of transformation, creation, and destruction of single quarks and leptons that allows atomic matter to exist, the Sun to shine, and the information-rich Periodic Table of the Elements to be built. The universe remains a single connected unit - not only in space, but in time and historic spacetime - a connectivity that is essential to its proper functioning and conservation.
Particles and the Spacetime Metric
I believe that during the "Big Bang", the interaction of (very high-energy) light with the metric structure of spacetime and the four forces of physics created massive particles: free electromagnetic energy was converted into bound electromagnetic energy, although the details of this primordial interaction remain unknown. This interaction includes gravity during the initial moments of creation. This sketchy scenario nevertheless suggests that the structure of spacetime may well be the source for the structure of particles, and one might reflect the other in some transformed parallelism. For example, the three energy "families" of quarks and leptons may reflect the 3 dimensions of space. We have no better explanation for the existence of these 3 energy families. The interaction between particles and the geometry of spacetime is currently being investigated by "string" theory (see Brian Greene's book "The Elegant Universe"). The IVBs are not "strings", but they may be analogs of "strings".
In the 4x4 matrix representation of the unified field theory (see table), we have 2 pairs of forces: the long-range or spacetime forces (electromagnetism and gravitation), and the short-range or particle forces (strong and weak). It may be these force pairs are in some sense transformed analogs of each other. For example, we have in the spacetime force pair the electromagnetic force representing a symmetric free energy input, while asymmetric gravitation transforms 3-dimensional space into linear time, maintains contact between matter and the spacetime metric, and gravity's product (time) represents an alternative entropy carrier, conserving energy and causality and allowing the transformation of energy to work. In the analogous case of the particle force pair, the strong force represents a symmetric bound energy input, while the asymmetric weak force transforms 3-dimensional quarks into point-like leptons (as in the "beta decay" of a neutron to a proton, electron, and electron antineutrino), maintains contact with the virtual particle sea, and the weak force product (leptons) represents an alternative charge carrier, conserving symmetry and charge and allowing the transformation of energy to information. (See: "The Strong and Weak Short-Range Particle Forces".)
This parallelism becomes evident only upon the effective arrangement of the 4x4 matrix of particles, charges, and forces - which like the Periodic Table of the Elements, carries an intrinsic level of information when properly configured and interpreted.
The Weak Force Mechanism
See: The "W" IVB and the Weak Force Mechanism
Leptons and the "Identity" Charge
See: Identity Charge and the Weak Force
Particles and Neutrinos
Recent observations suggest that the neutrino series itself may spontaneously "decay", oscillate, or transform into one another, much as their massive leptonic counterparts do (but in the latter case, with the necessary mediation of the massive "W" IVB family). (There may also be a 4th undiscovered neutrino which carries the identity charge of the primordial leptoquark, but this cannot be observed until we observe either leptoquark or proton (baryon) creation or decay). The lesson to be learned from the tau cascade decay-reaction is straightforward: elementary massive leptonic particles cannot be created or destroyed unless their identity charges are conserved by neutrinos. In fact, it is the presence of a neutrino which identifies a truly elementary particle. This is strict charge conservation operating again, telling us that an important symmetry of light, "anonymity", has been broken, and by Noether's Theorem requires conservation. The same system does not operate for the quarks (there are no quark neutrinos), evidently because quarks are not elementary particles, rather they are sub-elementary particles. I presume the identity system in this case operates only at the elementary (leptonic) level of particles, which in the case of quarks and baryons corresponds to the primordial leptoquark. This leptoquark neutrino, however, can only be seen, as mentioned above, if we observe a leptoquark creation or decay, or what is equivalent, a proton (baryon) creation or decay. (I presume that a single species of leptoquark neutrino suffices to represent the identity charge of all the many varieties of baryons - since all must return to the same single leptoquark configuration to decay.)
The simple view of neutrino function presented above is correct so far as leptonic decays are concerned. However, this picture has recently become more complicated by the discovery of neutrino "mass states" and the oscillation of neutrino "flavors" in flight after the decay. Here symmetry conservation is apparently observed at the generic level of flavor, rather than the specific level - see the discussion below. (In a similar fashion, the presumed leptoquark neutrino is thought to code for the generic identity of all baryons, rather than any particular baryon "species".)
Neutrino Mass and Oscillations
See: Scientific American, May 2010 pages 38-45: "Through Neutrino Eyes" by Gelmini, Kusenko, and Weiler for an authoritative discussion of neutrino oscillation and mass.
According to Gelmini et al., neutrino mass is the basis upon which one neutrino is distinguished from another. Neutrinos oscillate not only between their 3 leptonic "flavors", but between 3 "mass states", and it is the relative proportion of these mass states that determines flavor. Because any neutrino flavor can exhibit any mass state, neutrinos evidently code for flavor identity at both the generic level of all lepton flavors, and at the specific level of a single leptonic flavor. This solves the "mystery of the missing solar neutrinos". (See: A. McDonald, J. Klein, and D. Wark: "Solving the Solar Neutrino Problem". Scientific American, April, 2003.) (See also: Science: Vol. 313, 21 July 2006, page 291, regarding neutrino oscillations). The situation is complex in that while an electron neutrino can only react with an electron (or positron), it may nevertheless change into a muon or tau neutrino during flight, and while in this new configuration, react only with a muon or tau (or their antiparticles). Hence while a specific neutrino flavor does code for and react with a single leptonic flavor, you can't be sure which neutrino flavor you are going to end up with, no matter what flavor you began with. However, because all neutrino flavors play the same game, in sum they balance out each other's charges.
The fluid mix of neutrino identities (in flight) reflects the fluid state of identity in the electroweak symmetric energy state generally, in which all leptonic identities are merged at their generic level, and likewise all quark identities are merged at their generic level. In the electroweak symmetric energy state (or during the electroweak era of the "Big Bang"), transformations of one leptonic flavor into another, or one quark flavor into another, were simply the normal course of events. This is the generic level of symmetry which the "W" family of IVBs recreates (and is how the "W" effects identity transformations), not the specific level of "broken" symmetry (individual identity) we experience today. Specific leptonic and quark identities "freeze out" or "crystalize" only in the cold ground state of our present electromagnetic era. In flight, the neutrino seems to at least partially return to this fluid state of electroweak generic identity. Oscillations or superpositions of identity also occur between other closely related (massive) particles as well, including the quarks of the "K-neutral long" and "K-neutral short" mesons, and even the proton/neutron "nucleons".
The leptonic mass series (electron, muon, tau) serves as an alternative charge carrier for two charges, the electric charge of the electromagnetic force, and the "identity" charge of the weak force. Electric charge is quite independent of mass, and serves only as a long-range "locator" charge, identifying the spacetime location of an electrically charged particle, in this way serving matter's eternal search for antimatter and a return to the symmetric energy state of light (via an annihilation reaction). It is the task of the weak force "identity" charge (AKA lepton "number" charge) to distinguish between the several massive leptons so that they may in fact identify and annihilate with their appropriate anti-partners, once the electric charge has performed its locating and motivating functions.
The leptonic series is distinguished only by mass and identity charge, and it is interesting to note that the several identity charges (as carried in explicit form by neutrinos) are also distinguished one from another by mass - in this case by the disparate proportionate allocation of the superimposed deBroglie mass waves of the three neutrino "flavors" (see the Gelmini article cited above). The weak force focus upon mass, whether in the Higgs boson and its associated IVBs, the leptonic spectrum, or the neutrinos, suggests that the force which creates the massive, material, and particulate universe uses mass (bound electromagnetic energy) in all cases as a hedge against the attenuating effects of entropy, whether spatial or temporal, in our rapidly expanding universe. Charges and massive particles are simply immune from entropic enervation by the expansion of the cosmos, hence both can and do serve as invariant conservation parameters in the economy of Natural Law.
The "W" IVB "family" recreates an invariant, primordial state of force-unification symmetry (the Electroweak Era) by virtue of its huge and quantized mass. In this state the three members of the leptonic elementary particle spectrum are all equivalent (a "generic" level of identity rather than a "specific" level of identity), and transformations of one leptonic species into another are accomplished as a matter of course. Now it is most curious to note that the observed oscillations of the neutrinos apparently preserve a "memory" of this same primordial "generic" symmetry state, and in this reflection we catch a glimpse of why both the IVBs and the neutrinos must share a massive parameter. The neutrino cannot interact unless the "memory" of the "generic" electroweak symmetric energy state it carries within itself can be recreated, matched, or decoded by the IVB field - a "lock and key" mechanism. There is something special about the mass state of a neutrino which allows it to interact with (and only with) the mass state of an IVB. Hence we arrive at the curious phenomenon of a particle which carries its charge (partly) in the form of mass, and yet can travel through light years of lead without interacting.
It has been suggested that the three-family structure of the particle spectrum (including the quarks) is necessary to produce the weak force asymmetry which allows the primordial creation of matter during the "Big Bang". (For example, the "three family" structure allows many more opportunities for the creation of electrically neutral leptoquarks during the "Big Bang". Electrically neutral leptoquarks (heavy analogs of the neutron) are deemed necessary to break the primordial symmetry of light and its particle-antiparticle pairs, leading to the creation of our asymmetric "matter-only" universe.) If this is true, the "harmonic" 3-part family structure of the elementary particles may have an ultimate explanation beyond simple "anthropic" necessity. Because "cosmological" neutrinos can carry, without interaction, significant amounts of energy (due to the phenomenon of relativistic mass?), they may have been instrumental in the dispersal of energy during the initial expansion of the Big Bang, preventing the collapse of the entire system into a cosmic-scale black hole.
The hypothetical leptoquark neutrino is a candidate for "dark matter". This neutrino could be quite massive (and therefore relatively slow moving?), and if it is sufficiently different from the other leptonic neutrinos, it may not participate in their "harmonic" spectrum and oscillations. It is "sterile" to the extent that it can only be seen during proton decay or proton creation - via the "X" IVB. The search for a "sterile" (non-interactive) 4th neutrino species is currently ongoing in both Europe and the US, as an internet search on the term will confirm. (See: Adrian Cho: "The Sterile Neutrino: Fertile Concept or Dead End?" Science Vol. 334 21 Oct., 2011 page 304-6.)
Hiding the Neutrino's Identity Charge
The charge conservation reason for hiding identity charge is simple. Since identity charge is a "handed" charge, as we know from the explicit example of the neutrino, massive leptons (such as the electron) cannot conserve this charge in its explicit form, since any massive particle can be either left- or right-handed in its spin orientation. "Hiding" the handed identity charge as an implicit lepton number charge renders this conservation dilemma moot, since in this hidden condition the charge exhibits no handed preference. Only during a weak force transformation involving the IVBs must the lepton "awaken" to its true identity and left-handed spin orientation.
We can think of neutrinos as traveling (existing) from one IVB "event" to another - almost as an airplane travels only between airports. Typically, the neutrino is "born" or initiated in an IVB event (for example, during the decay of a muon to an electron, in which both a muon neutrino and an electron antineutrino are produced (in all reactions below, antiparticles are underlined; the electroweak transformation matrix of the "W" IVB is represented by square brackets; virtual particle-antiparticle pairs of mesons and leptons are enclosed in parentheses)):
u-[ (e+ x e-) ]W- ---> vu + ve + e-
In such an initiating decay, neutrinos pick up their symmetry debt of "identity" and perform their function as alternative charge carriers (and conservers) of the muon's and electron's identity charges (which are "hidden" in the massive leptons). Subsequently, the neutrinos carry their charges through spacetime at nearly the speed of light until they engage in another IVB interaction in which their services as alternative charge carriers are required, or they are annihilated/neutralized by corresponding anti-charges. Neutrino oscillations during flight mean that weak force charge conservation may by observed at the generic level of lepton number rather than the specific level of lepton identity: what began as an electron neutrino may end up as a muon neutrino (and vice versa), etc. Once within the transformation matrix of the "W" IVB, however, oscillations cease and weak force charge is conserved at the specific level of lepton identity: electron neutrinos only react with electrons, etc. Below I give abbreviated examples of baryon transformations occurring in the Sun and in the neutrino detector (antiparticles are underlined):
Solar fusion: proton ---> neutron
uud+[ (du- x du+)(e- x e+) ]W+ ---> udd + ve + e+
Neutrino detector: neutron ---> proton
ve + udd[ (du+ x du-)(e+ x e-) ]W- ---> udu+ + e-
In the detector reaction, the incoming electron neutrino cancels identity charges with the positron of the leptonic particle-antiparticle pair, releasing the electron of the pair to the product. The positron's positive electric charge cancels the negative electric charge of the pion in the adjacent meson-anti-meson pair; the pion subsequently self-destructs. Meanwhile, the positive pion's anti- d quark annihilates one of the neutron's d quarks, replacing it with an u quark, and donates its electric charge to the product proton. All charges, leptonic and electric, are balanced from one side of the equation to the other.
For a more detailed explanation of these reactions and symbols see either "The Particle Table" or "The 'W' IVB and the Weak Force IVBs".
See also: Sverker Johansson's website for an
authoritative discussion of neutrinos and the "Soar Neutrino
"The Solar FAQ"
Electron and Neutrino Pair
(added Nov. 28, 2011)
In the case of electron-positron pair production, we need only supply enough energy to satisfy the rest mass of the pair according to Einstein's famous equation: E = mcc. However, in the creation of a matter-antimatter neutrino pair, with a very much smaller rest mass energy, we must supply enough energy to create a Z (neutral) IVB (about 91 MEV) - the equivalent of approximately 91 proton masses. Why this enormous difference between particles joined in the electroweak unification? In the case of the electron-positron pair, the weak force identity charges are hidden and balancing, so only the electromagnetic force boson (photon) need be involved to create the electric charges. However, in the case of the neutrino-antineutrino pair, there is no electric charge present and the neutrinos represent "bare" weak force identity charges, which can only be produced by a weak force boson, in this case the Z (neutral) IVB. Similarly, in the case of the production of an electron and electron antineutrino during the decay (for example) of a neutron (beta decay), a "bare" single antineutrino is produced (balancing the hidden "lepton number" or weak force "identity" charge of the electron). This bare, single neutrino (an explicit weak force identity charge) can only be created by a weak force IVB, in this case the W-.
The ability to "hide" neutrinos or weak force "identity" charges is what determines the members of the massive leptonic spectrum or series - the electron, muon, and tau, and in all probability, the leptoquark. The leptoquark is the heaviest member of the series and progenitor of the proton, neutron, and hyperons, providing the missing link between leptons and quarks.
The ability to hide the weak identity charge in
leptonic alternative charge carriers is absolutely necessary for
weak-force symmetry-breaking via the production of single matter
baryons from electrically neutral leptoquark-antileptoquark
pairs during the "Big Bang" - since by this means charge
conservation is satisfied despite breaking the symmetry of
matter/antimatter pairs. (See: "The Formation of
Matter and the Origin of Information".)
Another view of the problem of identity charge
conservation by massive neutrinos is that this immediately
explains why neutrinos are so light and why (consequently) they
move so fast - nothing except light itself moves as fast as
neutrinos. Hence, the handedness of neutrinos cannot be reversed
simply by overtaking them in flight, and the conservation of
handedness is accomplished by super-fast neutrinos despite the
fact that they have a tiny mass.
Hence the high energy regime of the IVBs and the weak force identity charges follows the usual and logical pattern that higher energy processes nearer in time (and space) to the Big Bang lay the foundation and pave the way for the lower energy phenomena which follow - all the way down the scale to the electron shell chemistry of life.
The interior of stars, where the transmutation
of particles and the building of the heavy nuclei of "metallic"
elements is on-going, is the current locus of weak force
activity. Metaphorically, we can think of the stars as bits torn
off the Big Bang and scattered throughout space and time, bits
reconstituted by the negative energy and entropy of gravity, the
ancient era of the electroweak unification at least partially
recapitulated and still blazing in the cold sky of our