Physics:Quantum Standard Model

From HandWiki
Short description: Theory of forces and subatomic particles

← Back to Quantum field theory

The Standard Model of particle physics is the theory describing three of the four known fundamental forces (electromagnetic, weak and strong interactions – excluding gravity) in the universe and classifying all known elementary particles. It was developed in stages throughout the latter half of the 20th century, through the work of many scientists worldwide,[1] with the current formulation finalized in the mid-1970s upon experimental confirmation of the existence of quarks. The Standard Model is a paradigm of a quantum field theory, exhibiting phenomena such as spontaneous symmetry breaking, anomalies, and renormalization.[2]

Standard Model: unified description of strong, weak, and electromagnetic interactions in quantum field theory

Gauge structure

The Standard Model is defined by the gauge symmetry:

SU(3)×SU(2)L×U(1)Y

which corresponds to:

This symmetry determines the allowed interactions and particle content.[3]

Particle content

All particles can be classified into fermions and bosons.

Fermions

The Standard Model includes 12 fermions of spin 12, grouped into three generations.[4]

  • Quarks: up, down, charm, strange, top, bottom
  • Leptons: electron, muon, tau and their neutrinos

Quarks carry color charge and participate in the strong interaction, while leptons do not.

Fermions obey the Pauli exclusion principle and constitute all ordinary matter.[5]

Gauge bosons

Gauge bosons mediate the fundamental interactions:

  • Photon → electromagnetic force
  • Gluons → strong interaction
  • W and Z bosons → weak interaction

These arise from the gauge symmetry of the theory and act as force carriers.[6]

Higgs boson

The Higgs boson is a scalar particle responsible for mass generation via the Higgs mechanism.[7][8][9]

The Higgs field acquires a vacuum expectation value:

⟨ϕ⟩≠0

which leads to:

  • masses for W and Z bosons
  • masses for fermions
  • a massless photon
Overview of the Standard Model sectors and interactions

Lagrangian structure

The Standard Model is formulated as a quantum field theory with a Lagrangian composed of several sectors:

  • Quantum chromodynamics (QCD)
  • Electroweak sector
  • Higgs sector
  • Yukawa interactions

Each sector respects gauge invariance and contributes to the dynamics of particles and interactions.[10]

Fundamental interactions

The Standard Model describes three fundamental interactions:

  • Electromagnetism
  • Weak interaction
  • Strong interaction

These interactions arise from the exchange of gauge bosons between particles.[11]

Gravity is not included due to incompatibility with quantum field theory.[12]

Experimental confirmation

The Standard Model has been confirmed by numerous experiments, including:

  • discovery of quarks
  • observation of W and Z bosons
  • discovery of the Higgs boson (2012)[13]

Its predictions agree with experimental data to high precision.[14]

Limitations

Despite its success, the Standard Model is incomplete:

  • does not include gravity
  • does not explain dark matter or dark energy
  • does not explain matter–antimatter asymmetry
  • originally did not include neutrino masses

These issues motivate theories beyond the Standard Model.[15][16]

Historical development

The development of the Standard Model involved key contributions:

  • Dirac equation (1928) introducing antimatter[17]
  • Yang–Mills theory (1954) extending gauge symmetry[3]
  • Electroweak unification (Glashow, Weinberg, Salam)[18][19]
  • Introduction of quarks (Gell-Mann, Zweig)[20]
  • Higgs mechanism (1964)[7]
  • Asymptotic freedom in QCD (1973)[21][22]

These developments established the modern framework of particle physics.

Conceptual role

The Standard Model represents the culmination of:

  • gauge symmetry principles
  • non-Abelian gauge theory
  • quantum field theory

It unifies QED, QCD, and electroweak theory into a single framework describing fundamental interactions.[23]

See also

Table of contents (137 articles)

Index

Full contents

1. Foundations (7)
  1. Physics:Quantum basics
  2. Physics:Quantum Postulates
  3. Physics:Quantum Hilbert space
  4. Physics:Quantum Observables and operators
  5. Physics:Quantum mechanics
  6. Physics:Quantum mechanics measurements
  7. Physics:Quantum Mathematical Foundations of Quantum Theory

2. Conceptual and interpretations (10)
  1. Physics:Quantum Interpretations of quantum mechanics
  2. Physics:Quantum Wave–particle duality
  3. Physics:Quantum Complementarity principle
  4. Physics:Quantum Uncertainty principle
  5. Physics:Quantum Measurement problem
  6. Physics:Quantum Bell's theorem
  7. Physics:Quantum Hidden variable theory
  8. Physics:Quantum A Spooky Action at a Distance
  9. Physics:Quantum A Walk Through the Universe
  10. Physics:Quantum The Secret of Cohesion and How Waves Hold Matter Together

3. Mathematical structure and systems (11)
  1. Physics:Quantum Density matrix
  2. Physics:Quantum Exactly solvable quantum systems
  3. Physics:Quantum Formulas Collection
  4. Physics:Quantum A Matter Of Size
  5. Physics:Quantum Symmetry in quantum mechanics
  6. Physics:Quantum Angular momentum operator
  7. Physics:Runge–Lenz vector
  8. Physics:Quantum Approximation Methods
  9. Physics:Quantum Matter Elements and Particles
  10. Physics:Quantum Dirac equation
  11. Physics:Quantum Klein–Gordon equation

4. Atomic and spectroscopy (11)
    Quantum atomic structure and spectroscopy: orbitals, energy levels, and emission and absorption spectra.
  1. Physics:Quantum Atomic structure and spectroscopy
  2. Physics:Quantum Hydrogen atom
  3. Physics:Quantum Multi-electron atoms
  4. Physics:Quantum Fine structure
  5. Physics:Quantum Hyperfine structure
  6. Physics:Quantum Isotopic shift
  7. Physics:Quantum Zeeman effect
  8. Physics:Quantum Stark effect
  9. Physics:Quantum Spectral lines and series
  10. Physics:Quantum Selection rules
  11. Physics:Quantum Fermi's golden rule

5. Wavefunctions and modes (8)
    A quantum wavefunction showing probability amplitude in space; the square of its magnitude gives the probability density.
  1. Physics:Quantum Wavefunction
  2. Physics:Quantum Superposition principle
  3. Physics:Quantum Eigenstates and eigenvalues
  4. Physics:Quantum Boundary conditions and quantization
  5. Physics:Quantum Standing waves and modes
  6. Physics:Quantum Normal modes and field quantization
  7. Physics:Number of independent spatial modes in a spherical volume
  8. Physics:Quantum Density of states

6. Quantum dynamics and evolution (9)
  1. Physics:Quantum Time evolution
  2. Physics:Quantum Schrödinger equation
  3. Physics:Quantum Time-dependent Schrödinger equation
  4. Physics:Quantum Stationary states
  5. Physics:Quantum Perturbation theory
  6. Physics:Quantum Time-dependent perturbation theory
  7. Physics:Quantum Adiabatic theorem
  8. Physics:Quantum Scattering theory
  9. Physics:Quantum S-matrix

7. Measurement and information (6)
  1. Physics:Quantum Measurement theory
  2. Physics:Quantum Measurement operators
  3. Physics:Quantum Projective measurement
  4. Physics:Quantum POVM
  5. Physics:Quantum Weak measurement
  6. Physics:Quantum Measurement collapse

8. Quantum information and computing (6)
  1. Physics:Quantum information theory
  2. Physics:Quantum Qubit
  3. Physics:Quantum Entanglement
  4. Physics:Quantum Gates and circuits
  5. Physics:Quantum Computing Algorithms in the NISQ Era
  6. Physics:Quantum Noisy Qubits

9. Quantum optics and experiments (4)
    Experimental quantum physics: qubits, dilution refrigerators, quantum communication, and laboratory systems.
  1. Physics:Quantum Nonlinear King plot anomaly in calcium isotope spectroscopy
  2. Physics:Quantum optics beam splitter experiments
  3. Physics:Quantum Ultra fast lasers
  4. Physics:Quantum Experimental quantum physics
    5. Template:Quantum optics operators

10. Open quantum systems (7)
  1. Physics:Quantum Open systems
  2. Physics:Quantum Master equation
  3. Physics:Quantum Lindblad equation
  4. Physics:Quantum Decoherence
  5. Physics:Quantum Markovian dynamics
  6. Physics:Quantum Non-Markovian dynamics
  7. Physics:Quantum Trajectories

11. Quantum field theory (18)
    Structural dependency map of quantum field theory.
  1. Physics:Quantum field theory (QFT) basics
  2. Physics:Quantum field theory (QFT) core
  3. Physics:Quantum Fields and Particles
  4. Physics:Quantum Second quantization
  5. Physics:Quantum Harmonic Oscillator field modes
  6. Physics:Quantum Creation and annihilation operators
  7. Physics:Quantum vacuum fluctuations
  8. Physics:Quantum Propagators in quantum field theory
  9. Physics:Quantum Feynman diagrams
  10. Physics:Quantum Path integral formulation
  11. Physics:Quantum Renormalization in field theory
  12. Physics:Quantum Renormalization group
  13. Physics:Quantum Field Theory Gauge symmetry
  14. Physics:Quantum Non-Abelian gauge theory
  15. Physics:Quantum Electrodynamics (QED)
  16. Physics:Quantum chromodynamics (QCD)
  17. Physics:Quantum Electroweak theory
  18. Physics:Quantum Standard Model

12. Statistical mechanics and kinetic theory (10)
  1. Physics:Quantum Statistical mechanics
  2. Physics:Quantum Partition function
  3. Physics:Quantum Distribution functions
  4. Physics:Quantum Liouville equation
  5. Physics:Quantum Kinetic theory
  6. Physics:Quantum Boltzmann equation
  7. Physics:Quantum BBGKY hierarchy
  8. Physics:Quantum Transport theory
  9. Physics:Quantum Relaxation and thermalization
  10. Physics:Quantum Thermodynamics

13. Condensed matter and solid-state physics (7)
  1. Physics:Quantum Band structure
  2. Physics:Quantum Fermi surfaces
  3. Physics:Quantum Semiconductor physics
  4. Physics:Quantum Phonons
  5. Physics:Quantum Electron-phonon interaction
  6. Physics:Quantum Superconductivity
  7. Physics:Quantum Topological phases of matter

14. Plasma and fusion physics (9)
    Conceptual illustration of plasma physics in a fusion context, showing magnetically confined ionized gas in a tokamak and the collective behavior governed by electromagnetic fields and transport processes.
  1. Physics:Quantum Plasma (fusion context)
  2. Physics:Quantum Fusion reactions and Lawson criterion
  3. Physics:Quantum Magnetic confinement fusion
  4. Physics:Quantum Inertial confinement fusion
  5. Physics:Quantum Plasma instabilities and turbulence
  6. Physics:Quantum Tokamak
  7. Physics:Quantum Tokamak core plasma
  8. Physics:Quantum Tokamak edge physics and recycling asymmetries
  9. Physics:Quantum Stellarator

15. Timeline (7)
  1. Physics:Quantum mechanics/Timeline
  2. Physics:Quantum mechanics/Timeline/Pre-quantum era
  3. Physics:Quantum mechanics/Timeline/Old quantum theory
  4. Physics:Quantum mechanics/Timeline/Modern quantum mechanics
  5. Physics:Quantum mechanics/Timeline/Quantum field theory era
  6. Physics:Quantum mechanics/Timeline/Quantum information era
  7. Physics:Quantum_mechanics/Timeline/Quiz/

16. Advanced and frontier topics (6)
  1. Physics:Quantum Supersymmetry
  2. Physics:Quantum Black hole thermodynamics
  3. Physics:Quantum Holographic principle
  4. Physics:Quantum gravity
  5. Physics:Quantum De Sitter invariant special relativity
  6. Physics:Quantum Doubly special relativity

References

  1. ↑ R. Oerter (2006). The Theory of Almost Everything: The Standard Model, the Unsung Triumph of Modern Physics. Penguin Group. p. 2. ISBN 978-0-13-236678-6. 
  2. ↑ R. Mann (2010). An Introduction to Particle Physics and the Standard Model. CRC Press. doi:10.1201/9781420083002-25. 
  3. ↑ 3.0 3.1 C. N. Yang; R. Mills (1954). "Conservation of Isotopic Spin and Isotopic Gauge Invariance". Physical Review 96: 191–195. 
  4. ↑ "The Standard Model". https://www-project.slac.stanford.edu/e158/StandardModel.html. 
  5. ↑ Jens Eisert (2013). "Pauli Principle, Reloaded". Physics. 
  6. ↑ Gregg Jaeger (2021). "Exchange Forces in Particle Physics". Foundations of Physics. 
  7. ↑ 7.0 7.1 P. W. Higgs (1964). "Broken Symmetries and the Masses of Gauge Bosons". Physical Review Letters. 
  8. ↑ F. Englert; R. Brout (1964). "Broken Symmetry and the Mass of Gauge Vector Mesons". Physical Review Letters. 
  9. ↑ G. S. Guralnik; C. R. Hagen; T. W. B. Kibble (1964). "Global Conservation Laws and Massless Particles". Physical Review Letters. 
  10. ↑ S. Weinberg (2004). "The making of the Standard Model". European Physical Journal C. 
  11. ↑ "The Standard Model". CERN. 2023. 
  12. ↑ Abhay Ashtekar (2005). "Gravity and the quantum". New Journal of Physics. 
  13. ↑ "Observation of a New Particle with a Mass of 125 GeV". CERN. 2012. 
  14. ↑ Mary K. Gaillard (1999). "The Standard Model of Particle Physics". Reviews of Modern Physics. 
  15. ↑ Overbye, Dennis (2023). "Don't Expect a 'Theory of Everything' to Explain It All". 
  16. ↑ Sean Carroll (2007). Dark Matter, Dark Energy: The Dark Side of the Universe. 
  17. ↑ "The Dirac equation unifies quantum mechanics and relativity". APS. 2024. 
  18. ↑ S. L. Glashow (1961). "Partial symmetries of weak interactions". Nuclear Physics. 
  19. ↑ S. Weinberg (1967). "A Model of Leptons". Physical Review Letters. 
  20. ↑ O. Greenberg (2009). Color Charge Degree of Freedom in Particle Physics. 
  21. ↑ D. Gross; F. Wilczek (1973). "Ultraviolet behavior of non-abelian gauge theories". Physical Review Letters. 
  22. ↑ H. Politzer (1973). "Reliable perturbative results for strong interactions". Physical Review Letters. 
  23. ↑ Gregg Jaeger (2021). "The Elementary Particles of Quantum Fields". Entropy. 
Author: Harold Foppele





Retrieved from "https://handwiki.org/wiki/index.php?title=Physics:Quantum_Standard_Model&oldid=4297521"