Standard Model of Particle Physics

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Table of Contents

  1. Overview
  2. What the Standard Model Explains
  3. Quantum Fields
  4. Elementary Particles
  5. Fundamental Interactions and Feynman Diagrams
  6. Two Fundamental Theories of Physics
    1. General Relativity
    2. Standard Model of Particle Physics
  7. Nuclear Fission and Fusion
  8. Observations and Experiments
  9. Quantum Field Theory (QFT)
  10. Development of the Standard Model


  • The core idea of the Standard Model is the Quantum Field.
    • Quantum Fields are the fundamental entities of the universe.
    • Particles are their localized vibrations.
  • Three kinds of Elementary Fields / Particles:
    • Matter
      • Kinds
        • Leptons
        • Quarks
      • Matter particles make up Composite Particles
        • For example, quarks make up protons and neutrons
    • Higgs
      • Provides mass to other particles
    • Exchange
      • Forces operate through Exchange Particles (aka Messenger Particles, Force-Carrier Particles, Gauge Bosons).
      • SMPP governs three of the four fundamental forces.
        • Electromagnetic Interaction
        • Strong Interaction
        • Weak Interaction
  • Particles have Antimatter counterparts
    • For example, electrons have positrons and protons have antiprotons.
    • When a particle collides with its antiparticle they annihilate each other, releasing large amounts of energy in the form of gamma rays or elementary particles.
  • Quantified Field Theory provides the equations governing the interactions among fields, particles, and forces.
    • Quantified Field Theory consists of
      • Quantum Electrodynamics (QED), governing the electromagnetic field.
      • Electroweak Theory (EWT), governing both the electromagnetic force and the weak force.
      • Quantum Chromodynamics (QCD), governing the strong force.
  • Data is gathered and predictions tested by
    • conducting laboratory experiments
    • observing cosmic rays
    • conducting experiments with particle accelerators
  • Energy, linear momentum, angular momentum, and electric charge obey Conservation Laws, keeping the same values through particle reactions.
  • Most subatomic particles exist for less than a millionth of a second

What the Standard Model Explains

  • Nature and behavior of elementary particles
    • Matter, Higgs, Exchange
  • Nature and behavior of composite particles
    • Protons, neutrons, atoms, ions, molecules
  • Nuclear reactions (change in the identity or characteristics of an atomic nucleus)
    • e.g. radioactivity, nuclear fission, nuclear fusion
  • Chemical reactions (rearrangement of the atoms of elements and compounds)
  • Chemical bonding (interactions by which atoms form molecules, ions, crystals, and other entities of the physical world)
  • Interaction between matter and electromagnetic radiation

Quantum Fields

  • Quantum Fields are the fundamental entities of the universe.
  • The fields are observed as particles, leaving tracks and traces in particle accelerators and cosmic ray detectors.

View Quantum Fields

Elementary Particles

View Elementary Particles

Fundamental Interactions and Feynman Diagrams

  • All forces of nature derive from four Fundamental Interactions (or Forces), which govern how particles interact and, in some cases, decay:
    • Electromagnetism
    • Strong Force
    • Weak Force
    • Gravity
  • The Standard Model governs the first three; General Relativity the last.

View Fundamental Interactions and Feynman Diagrams

Two Fundamental Theories of Physics

General Relativity
  • Developed by Albert Einstein from 1907 to 1915
  • Governs
    • Gravitational Force
  • Basic Idea
    • Gravity is Curved Spacetime
  • Confirmed Predictions
    • Gravitational Time Dilation, Gravity Waves, Gravitational Redshift, Gravitational Time Delay of Light, Mercury’s Orbit, Gravitational Deflection of Light
Standard Model of Particle Physics
  • Developed by dozens of physicists from the 1940s to the 1970s
  • Governs
    • Electromagnetic Force
    • Strong Nuclear Force
    • Weak Nuclear Force
  • Basic Idea
    • The fundamental entities of the universe are Quantum Fields
  • Confirmed Predictions
    • Existence of W and Z bosons (1983), top quark (1995), tau neutrino (2000), and Higgs Boson (2012)

Nuclear Fission and Fusion

In nuclear fission and fusion the mass of the reacting particles is greater than the mass of the product particles, the lost mass converted into energy per Einstein’s E=mc2.

View Nuclear Fission and Fusion

Observations and Experiments

Quantum Fields are detected only by their particles, which in turn are detected only by their tracks and traces, in some cases only by the tracks and traces of their debris.

View Observations and Experiments

Quantum Field Theory (QFT)

Quantum Field Theory, a collection of three theories, provides the equations governing the interaction among the fields, particles, and forces of the Standard Model:

View Quantum Field Theory (QFT)

Development of the Standard Model

From Newton to the Nobel laureates of the Standard model

View Development of the Standard Model