h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

There are two classes of elementary particles Leptons and Bosons.
Examples of Bosons are protons, neutrons and mesons, and they are made of quarks. Examples of Leptons are electrons and positrons, and they are not made of quarks.
Either bosons or leptons may have an electronic charge, for example the electron's negative charge, and the proton's positive charge.
Now, my question is this: if these two classes of particles are so different, with no common component in their makeup (one has quarks, the other doesn't) they why does the magnitude of the electron's charge EXACTLY equal the magnitude of the proton's charge?

Protons are not bosons. They are a composite particle with half integer spin meaning they obey Fermi-Dirac statistics (Pauli principle etc).

Bosons obey Bose-Einstein statistics - composite particles with integer spin such as helium nuclei are bosons.

As to the charge thing - you need a particle physicist for that which I am not sadly.

Also really the two fundamental classes of elementary particles according to the standard model are strictly fermions (of which quarks and leptons are subclasses) and bosons.

As I understand it (which isn't very well) charge and gravity are theorised to arise from exchange of bosons between quarks and leptons - the famed Higgs boson is the one that defines gravity (i.e. mass). for example.

Nope that's a graviton, as you were…

Anyway, exchange of the same boson will lead to equal and opposite charge between the two particles exchanging.


I wouldn't try too hard to understand it frankly. It's deeply theoretical and even the big physics profs would (do) warn against trying to visualise it too hard.

Why does the electron or anti-electron have a charge exactly matching that of the anti-proton or proton?

I think that the answer to that one is that no one knows.

Though one can study how charge behaves and describe that behavior with mathematical laws, the actual structure of the lepton is in a range of undeterminability below the level of Heisrnberg's uncertainty
threshold.

Leptons and bosons do have in in common that all of there charactetistics are reducible

Ooops!

Moving from Pliny to Brunel.

Why does the electron or anti-electron have exactly the same charge as the anti-proton or proton?

I think that the answer to that one is that no one knows.

Though one can study how charge behaves and describe that behavior with mathematical laws, the actual internal structure of the lepton is in a range of undeterminability below Heisenberg's uncertainty threshold.

Leptons and bosons do have in common the point that all of their properties are reducible to integer multiples of Planck's elementary quantum, which can manifest as either a whole unit of momentum or a half unit of spin.

Classical experiments involving protons bombarded with electrons show that in such a case, the proton having absorbed the electron, the proton converts to a neutron, with an increase of rest mass in the amount of the rest mass of the electron.

If one bombards neutrons with anti-electrons, the neutron having absorbed the anti-electron, converts into a proton, with a loss of rest mass in the amount the rest mass of the electron.

Photons and gravitons are the same for either matter or anti-matter, which cannot be told apart on a basis of their interactions with either light or gravity.

Electrons and anti-electrons have the same rest mass.

Protons and anti-protons have equal rest masses.

Neutrons and anti-neutrons have matching rest masses, lacking net charge, differ on the point that they have opposite spins, as do protons and anti-protons.

The rest masses of the proton and the neutron, besides differing in the amount of a single electron rest mass, both have rest masses that are integer multiples of the rest mass of the electron.

This is the basis of the poly-electron model of baryonic structure.

Finding research tools that allow one to probe the internal structures of either leptons or baryons is a difficult trick.

Most theory on that is the realm of string theory, which, taking the elementary quantum as the fundamental building block of all higher forms of matter and energy, attempts to infer the properties of higher forms of matter and energy from that fundamental building block and the relevant physical laws.

On the question of charge, no one really knows what it is, all one can observe is how it behaves.

Thanks for that, folks...

Can't say I understand much (any?) of it, but a few grey areas have lightened a little...

Neutrinos were discovered on a basis of study of beta decay (electron emission) of neutrons, initially predicted by Enrico Fermi on a basis of an energy deficit in the beta decay, it was quite some time before their existence was experimentally confirmed.

An alternative viewpoint on quark confinement is founded on the point that with muon and pion decay, the decay yeilds a neutrino, an anti-neutrino and, respectively, an electron or anti-electron.

The muon and pion, like other mesons, being a combination of a quark and an anti-quark, one can infer that the quarks are confined since the electron or anti-electron supplying the bonding energy between the neutrino/anti-neutrino pair is indivisable and quark confinement collapses with the emission of that electron.

The neutrinos and anti-neutrinos in this case actually have enormously higher elementary quantum equivalencies than the electron, but like all neutrinos, interact only very weakly with conventional matter.

Yet another view, suggested by John Archibald Wheeler, is that pions and muons are really only high energy anti-electrons and electrons carrying an enormous relativistic mass increase, which decays with the emission of the bonding anti-electron or electron, yeilding the relativistic mass increase, which originated in the form of momentum applied to anti-electron or electron in the form of a neutrino/anti-neutrino pair.

All of these viewpoints can simultaneously be true and correct.

There are also uncharged mesons which can still be analyzed in terms of quark/anti-quark pairs.




All of that has a cosmological consequence.

Besides the primordial hydrogen and helium yielded by the big bang, how many neutrons?

Neutrons are no more unlikely as products of the big bang than protons and electrons.

I wish I had answer to that one.

You seem to know more about this than me (my tutoring is limited to what is required by chemists). Can I ask some supplementary questions?

I know that the amount of deuterium in existence was determined by cooling milliseconds (?) after the big bang. Were all the original neutrons trapped into heavy hydrogen (deuterium) nuclei?

As a supplementary question - heavy nuclei (anything above Iron 57) are known to require a supernova to create them as you are creating less thermodynamically stable nuclei (lower nuclear binding force) and require rapid neutron bombardment - faster than nuclear decay - to put enough nucleons in there before decay to a stable nucleus occurs.
Why was the big bang not also capable of this…? Higher energy and denser than a Supernova surely...

On post 10, pretty much the questions that are puzzling me at the moment, with some supplementary lines of thought that may embody useful clues.

Homework to do.

should have been

A very good point. The Big Bang should have made the heavier elements. (If there was one; I am anti-big bang and tried to publish another steady state theory.)

I'm personally an advocate of the inflationary model and personally doubt that the universe could ever have been much smaller than it was at the terminus of the inflationary epoch.

Forcing the model back to a primordial point source is, I think, a case of pushing the mathematics beyond the limitations of its predictive value.

Its also my opinion that the observable universe is embedded in a larger plenum.

With respect to primordial matter, I think that the preponderance of it was in the form of Hawking's primordial black holes, black holes of substellar mass formed by the compressional forces operating in the early universe, too small for the gravitational collapse model to operate, with decay times depending very sensitively on their intrinsic mass equivalency and that the most common type of gamma ray burster, the galactic halo type, occurring out in the galactic halo where the dark matter is supposed to be, represent remnants of the primordial populatiion of Hawking's primordial black holes.

homework notes:

spin being counted in half units, bosons have even numbers of half units of spin, fermions have odd numbers of half units of spin.

http://www.google.com/search?q=tables,+fermions+and+bosons&lr=&as_qdr=all&tbm=isch&tbo=u&source=univ&sa=X&ei=azoEVeS-E8XZoASpiICABA&ved=0CEMQ7Ak&biw=960&bih=527

http://kias.dyndns.org/astrophys/particles.html