The Standard Model of Particle Physics Simplified
We explain the standard model of particle physics in simple terms for non-experts using videos, facts, and bullet points.
What is the Standard Model?
The standard model shows how elementary “quantum” particles interact to form the known universe (so it explains the fundamental building blocks of nature like quarks, electrons, and photons and their interactions). It sounds difficult, but it’s fairly simple once you understand the terms. Essentially, it works a lot like the atom you learned about in high school chemistry. In fact, it explains what an atom is made up of the same way that atoms explain what molecules are made up of, or the same way molecules explain what we are made of. Luckily, it is all governed by relatively few rules, which make it easy to learn.Theory of “Everything” (intro) – MinutePhysics. An introduction to the theory of [almost] everything, the standard model.
TIP: The Standard Model explains how the basic building blocks of matter interact, governed by four fundamental forces. That means on a fundamental level it is the theory of [almost] everything (aside from things like dark energy, the multiverse theories, string theory, etc). Learn more from CERN.
Standard Model Facts
Here are some standard model facts designed as a simple introduction and overview of the standard model of particle physics. See a more detailed breakdown of the standard model here.
- There are two types of elementary particles, Fermions (quarks and leptons) that form the basis of matter, and bosons that “mediate the interactions” between fermions.
- There is also a special type of boson; the”Higgs Boson” gives massless energy particles their mass.
- Each particle has an anti-particle or is its own anti-particle.
- When fermions interact they exchange virtual particles via the bosons.
- The four forces are electromagnetic force, gravitational force, weak nuclear force, and strong nuclear force. The two nuclear forces the hold particles together.
- In simple terms, each force has a corresponding boson. Importantly, the well-known photon is the only carrier of the electromagnetic force. The less common, but equally important gluon, “glues” composite particles together. Learn more about the four forces.
- There are still some things that the standard model doesn’t explain like dark energy, quantum gravity, and a few other complicated subjects. So it’s not a theory of everything.
- The best place for information on the standard model is CERN. I also love Fermilab’s YouTube channel and PBS spacetime. If something more basic is needed, SciShow is always a good choice.
- There are 17 known elementary particles (61 if you count versions of quark and gluon “colors”) that make up everything including all the fermions and bosons.
- Quark colors aren’t your usual colors, but just a model used to show how different quarks connect to make nuclei, protons, and neutrons. Words like color, flavor, and generation simply mean “type.”
- There are a lot of composite particles that elementary particles form temporarily when they break down or build up in uncommon ways. The standard model doesn’t explicitly count these, just as a periodic table doesn’t feature all states of each element.
- All particles are understood as particle-wave-fields, not a billiard ball, but a wave-like field with excited states called particles. Learn more about quantum field theory.
- All particles and forces can be explained in terms of mass-energy and motion. The only properties these elementary particles have can be measured as mass-energy and motion (i.e. charge, spin, mass, frequency).
- The only universal constants in the universe are related to the nature of mass-energy (light speed, Planck length, the gravitational force between two bodies). Almost all physics equations that explain the standard model have symbols relating to the universal constants and those variables like time and space which are relative from one’s frame of reference.
- The lepton or electron is the only non-quark part of atoms.
- Just like electrons in an atom, quarks have “charge” and spin which define how they can bind with other quarks via the strong force.
- Mass-energy can never be created or destroyed. By extension mass-energy and motion are always conserved as at least properties of elementary particles or the effects of composite particles.
- Atoms and some elementary particles are actually composite particles, at their core, all particles are thought to be massless energy particles.
FACT: At its core, chemistry is physics. All the periodic table elements are made from quantum particles.
|Total number of (known) elementary particles: