Understanding nature requires understanding its building blocks at a fundamental level.
And there can be little more fundamental in nature than the smallest of entities: the
In the chapter on particle physics we looked
at particles in general and there I hypothesised that all subatomic particles are
spherical, have the same diameter, and differ only in their mass and charge sign. Very
little is known about the internals of such particles. Still, it may be helpful to take
what little we know and extend this model to see what other properties might be determined
about particles and their components. Naturally much of this will be rather speculative
but here goes.
Well begin by looking at what subatomic particles are composed of.
As far as we know, a charged particle has two properties: mass and charge. Since these
properties are very different, its quite likely that each of them is contained
within separate regions of the particle. In the chapter on nucleon structure I speculated that
charge is mostly concentrated around the perimeter. And with heavier particles, the charge
concentration (density) is greater. So lets expand on that and say a charged
particle contains a solid core of mass surrounded by a thick mantle-like layer of charge.
Here is an example of two particles:
On the left is a lightweight particle, such as an electron. To the right
is a heavier particle, such as a down-quark. Both have the same size and charge. The
electrons mass-core is tiny and its charge-mantle thick. The down-quarks
mass-core is heavier and larger, requiring its charge-mantle to be thinner and more
So basically each subatomic particle contains a material we could call
mass-substance. This mass-substance has a fixed density, meaning that
particles having a larger mass will have a greater volume of it.
The other substance contained within particles is charge. Charge has two properties. One
is that it emits an electric field. The other is that it reacts to such fields, i.e. it
experiences force. The first of these is the most interesting. Charge emits something we
call electric field and does so continuously and without end. For this to be
true, either the charge contains an infinite amount of field, which it slowly
releases, or charge has the capacity to create field on-the-fly and without limit. Both of
these seem difficult to comprehend, especially given our understanding of energy
conservation. Yet one must be true because charges never lose their capacity to exert
force on other charges.
Putting that mystery aside, there is a more immediate problem at hand. We know that
identical charges repel, correct? Well the entire lump of charge contained within a
particle is basically an accumulation of identical sub-charges packed close together.
Those sub-charges must be constantly trying to repel each other. For example, the left and
right hand sides of an electron will be constantly pushing against each other. This raises
an obvious question of how an electron holds itself together. Put another way, why
dont charged particles blow themselves apart?
Internal binding holding things together
There are several clues at hand. The first comes from observing that
charged particles always contain mass we know of no massless charges. The second
clue is that when a charged particle is exposed to an electric field it experiences force,
but that force depends only on charge and not on mass. The third is that when the charge
responds to the force and starts moving, both charge and mass move together.
These clues indicate that the mass-core must be somehow bound to the surrounding
charge-mantle, otherwise it would be left behind when the charge moves. This binding
therefore, whatever it is, is quite likely what holds the charge together. Without a
mass-core, a concentration of charge could not exist and would fly apart.
A forth clue is the question of what holds the mass-core together. This would not seem to
be important because mass does not repel itself. But just because it doesnt repel
does not mean it should stay together. If the mass-core within charged particles is made
of some kind of dividable substance, then without any force holding it together, that
substance would drift apart. Therefore its possible the charge serves the purpose of
holding the mass together as well.
Arranging the components
So the hypothesis is this. Somehow an accumulation of mass-substance
attracts charge-substance and confines it within a fixed sized sphere. Once a fixed amount
of charge has been attracted, all attraction to additional charge ceases completely. At
that point, both mass and charge bind with each other and form a subatomic particle.
This raises two further questions: why a fixed amount of charge and why a fixed-size
The second can be answered with an analogy. Suppose we have two planets: one large, the
other small. We give each an equal amount of atmosphere. The large planet has a high
gravity and will compress its atmosphere into a narrow altitude. The small planet has low
gravity and doesnt compress the atmosphere very much. As a result, both planets,
including atmospheres, may end up a similar size.
Extending this analogy to charged particles, its possible that lightweight
particles (such as electrons) compress charge lightly, making their charge mantle thick.
Whereas particles with large amounts of mass will more strongly attract charge and
compress it better. As a result, particles with different masses may end up as similar
sized spheres, although not identical. This would also allow for very massive particles to
exist they would have even more compressed charge mantles.
As for the first question, why does the mass-core attract only a fixed amount of charge?
This is certainly a mystery. The only thing we can say is thats what it does and the
amount of charge contained in a particle is truly a universal quantum. At the point when
the mass-core has attracted that quantum of charge, its attraction to further charge
becomes zero. At that point, even if another charged particle should overlap the same
region, the mass from one will have no effect on the charge from the other.
Based on this requirement of a universal quantum of charge, it follows that a minimum
amount of mass would be required to attract that charge. A particle with less than that
amount would be unable to properly form because the repulsion within the charge substance
would push the particle apart. This minimum amount may correspond to an electrons
mass, or slightly less than that amount.
Its possible that subatomic particles consist of a mass-core
surrounded by a charge-mantle. The mass-core is made of mass-substance, is of
fixed density and variable volume. The charge-mantle contains a fixed quantity and
variable density of charge-substance. The mass and charge components bind each
other into a subatomic particle. All subatomic particles are either of the same size or of
a similar size.
Naturally this is somewhat speculative. As pointed out earlier, we have limited
information and may never know the interiors of charged particles. Although it is still
useful to take educated guesses with what little we have. This subject will be picked up
again in a later chapter on cosmology.