The Standard Model
This chart is what is known as the Standard Model. In it shows the elementary particles, i.e., particles which cannot be broken down any further. There are even more particles that we will be looking into. We see our old friend, the electron, but where’s the proton and neutron?
Well, we don’t see them, but we see their constituents, quarks. And better yet, those particles are held together by another particle– the gluon. Before we get ahead of ourselves, let’s go through all the particles in the chart:
These make up other particles, including the two nucleons, neutrons and protons. Quarks differ in their masses and electric charges (also, they’re the only particles to have fractional charges).
There are three main types with three neutrino counterparts, differing in mass and charge. Neutrinos have extremely tiny masses. In fact, billions are passing through your body every second!
These are called the force carriers. They are responsible for mediating the four fundamental forces-electromagnetic, strong nuclear force, weak nuclear force, and gravity…well, maybe gravity.
Four Fundamental Forces (FFF) and the Graviton
Since three of the FFF have a particle mediator, wouldn’t it make sense for gravity to have one? Enter the graviton. Gravitons are theoretical particles which are supposed to mediate gravitational force. Meanwhile, photons mediate electromagnetic force; W and Z bosons mediate the weak force; and gluons mediate the strong force. The strong force holds nuclei together, and the weak force holds together leptons and quarks. The weak force is also responsible for particle transmutation. Electromagnetism is seen in numerous ways, such as light, holding atoms together, friction, and lightning to name just a few. It’s also interesting to note that the electromagnetic and weak forces are often unified as one force- the electroweak force. At higher energies and smaller distances (attometers, or 10−18 meters), the two are essentially manifestations of the same thing.
The Notorious Higgs Boson and the Higgs Field
This is a special kind of boson which is responsible for giving objects their mass. Throughout the so-called Higgs Field, some particles interact with it and thus have a mass, whereas those which do not (photons) have no mass. In other words, particles have no mass until they interact with the Higgs field. The boson itself can be seen as the movement of the interactions of those particles within the field. Fermilab’s Senior Physicist Don Lincoln explains this visually with the analogy of a cocktail party.
Fermions, Bosons, and the Pauli Exclusion Principle (PEP)
“Fermion” is a name for any particle which obeys the PEP, while bosons do not. The PEP, simply put, states that no two particles can exist in the same spot at the same time. Imagine riding a roller coaster: the people riding it are particles, and only two can fit in each row. Since you cannot phase into the same spot somebody else is in, only two people can be in the row at once. This is the PEP. Okay, but how are there particles that can be in the same place at once? That’s because the roller coaster analogy is incomplete. The PEP states that two particles with the same spin cannot exist together in the same place, or quantum state. “Spin” is a shorthand for a particle’s intrinsic angular momentum; by nature, it “spins.” A “quantum state” is defined by specific properties and is not a physical location, as the reference to the analogy may suggest.
It sounds like something from an episode of Star Trek, but these are very real. For every particle, there is an antiparticle that is exactly the same as the original, except that it has an opposite electrical charge. The only boson with an antiparticle is the W boson, while the others are their own antiparticles. When an antiparticle and a particle collide, they annihilate each other and what’s left over is an immense amount of energy. Sometimes, as with muons and antimuons, other particles are produced. Do understand that this does not by any means say that mass or energy is created- the masses of the particles convert to energy and can be converted into mass. Remember E = mc2? Mass and energy are manifestations of the same thing.
If you’re reading a blog post about particle physics, you’ve likely heard of hadrons. More specifically, you may recognize it from the LHC, or Large Hadron Collider. There are two types of hadrons: baryons and mesons. Baryons are particles made up of 3 quarks (such as nucleons), and mesons are made of one quark and one antiquark.
Time to start getting theoretical. There is supposed by some scientists to exist a symmetric particle counterpart to every particle in existence. SUSY could link bosons and fermions together- a boson’s superpartner would be a fermion and a fermion’s superpartner would be boson. This would unify the particles which make up matter (fermions) and the particles which mediate forces (bosons).
I’m not even going deep into this one, but these are kind of particles and kind of not at the same time. They are used to describe properties in solids, or more technically, within and along their crystal lattice structures. Quasiparticles are property waves which describe things like heat transfer and vibrations. Scientifically speaking, they’re insane. But what’s more insane is that scientists have actually discovered these things. These are not just ideas or mathematically sound descriptions; they are real physical phenomena. For more info, click this link.
So the next time you wonder, “What is everything made of?” don’t think so much in terms of protons, neutrons, and electrons, but imagine a zoo of particles! Think of the particles making up those particles! Think of the particles that we may not have even found yet!
Just to blow your mind even further, it’s time to undermine this entire post and your understanding with this closing statement.
Nothing is made of particles, but everything is made of fields.