Subatomic Particles

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 subatomic particle.

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.


Subatomic components

We’ll 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, it’s 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 let’s 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:

electron and muon

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 electron’s mass-core is tiny and its charge-mantle thick. The down-quark’s mass-core is heavier and larger, requiring its charge-mantle to be thinner and more concentrated.

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 don’t 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 doesn’t 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 it’s 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 sphere?

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 doesn’t compress the atmosphere very much. As a result, both planets, including atmospheres, may end up a similar size.

Extending this analogy to charged particles, it’s 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 that’s 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 electron’s mass, or slightly less than that amount.



It’s 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.


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Copyright 2010 Bernard Burchell, all rights reserved.