A Gauge Theory for the Weak and Electromagnetic Interactions

2021 ◽  
pp. 388-404
Author(s):  
J. Iliopoulos ◽  
T.N. Tomaras
Keyword(s):  
Gauge Theory ◽  
Quark Model ◽  
Weak Interactions ◽  
Mass Matrix ◽  
Natural Source ◽  
Apparent Difference ◽  
Electromagnetic Interactions ◽  
Vector Bosons ◽  
Gim Mechanism ◽  
Intermediate Vector

In this chapter we develop the Glashow–Weinberg–Salam theory of electromagnetic and weak interactions based on the gauge group SU(2) × U(1). We show that the apparent difference in strength between the two interactions is due to the Brout–Englert–Higgs phenomenon which results in heavy intermediate vector bosons. The model is presented first for the leptons, and then we argue that the extension to hadrons requires the introduction of a fourth quark. We show that the GIM mechanism guarantees the natural suppression of strangeness changing neutral currents. In the same spirit, the need to introduce a natural source of CP-violation leads to a six quark model with the Cabibbo–Kobayashi–Maskawa mass matrix.

Introductory remarks about new particles

1977 ◽  
Vol 355 (1683) ◽  
pp. 443-445 ◽  
Keyword(s):  
Particle Physics ◽  
Direct Detection ◽  
Weak Interactions ◽  
Heavy Particle ◽  
New Era ◽  
Elementary Particle Physics ◽  
Electromagnetic Interactions ◽  
Vector Bosons ◽  
First Time ◽  
New Particles

On 11 November 1974, elementary particle physics entered a new era, with simultaneous announcements from the east and west coasts of America that a new heavy particle with astonishingly small decay width had been observed in two quite independent experiments, of different types. Since that time we have all been living through one of the most exciting periods which our field of research has known. The possibility that there might exist new particles of some kind, and possibly of more than one kind, was very much ‘in the air’ during the preceding year or so (Iliopoulos 1974). Attractive theoretical ideas had been put forward some years before (Weinberg 1967) suggesting that a finite gauge theory could be constructed for the weak interactions, which could achieve a unification of the weak and electromagnetic interactions, a goal long sought (Salam & Ward 1964). When a proof of this finiteness (renormalizability) was achieved by t’Hooft (1971 a , b ), physicists had for the first time calculable and meaningful theories unifying the weak and electromagnetic interactions, the analogue for the weak interactions to the photon for the electromagnetic field being very heavy vector bosons, both charged and neutral, whose direct detection still lies quite far in the future. However, not all such theories were necessarily finite. Further conditions had to be met, and a key feature of these is the situation concerning the neutral weak currents.

scholarly journals Astrophysical Consequences of the Existence of Charged Intermediate Vector Bosons

1968 ◽  
Vol 21 (2) ◽  
pp. 139 ◽  
Author(s):  
JA Campbell
Keyword(s):  
Weak Interactions ◽  
Vector Boson ◽  
Accurate Information ◽  
Coupling Constant ◽  
Evolutionary Time ◽  
Two Photon ◽  
Vector Bosons ◽  
Intermediate Vector ◽  
Photon Annihilation ◽  
Intermediate Vector Boson

Two-photon annihilation into a neutrino-antineutrino pair, which is forbidden to the lowest order in the coupling constant for weak interactions if the conventional form of weak interaction is assumed, is permitted at that order if it is supposed that the reaction is carried by a charged intermediate vector boson (W). The rate of loss of energy in stellar evolution through this process is calculated. Evolutionary time scales derived with and without this rate are compared with results from astronomical observations. Comparisons with present data are inconclusive, but further observations and calculations that may give more accurate information concerning the question of the existence of charged W mesons are suggested.

More on the Fundamental Forces and Their “Carriers”

2018 ◽  
pp. 40-51
Author(s):  
Alvaro De Rújula
Keyword(s):  
Quantum Chromodynamics ◽  
Weak Interactions ◽  
Vector Bosons ◽  
Fundamental Forces ◽  
Intermediate Vector ◽  
The Way

A discussion of the “carriers” of the basic forces of nature and the way they “work.” Electrical charges and their interaction with photons (QED). Gravitons and the identity of inertial and gravitational masses. Intermediate vector bosons and the weak interactions. Gluons and the “chromodynamic” interactions (Quantum Chromodynamics: QCD). Adding electric charges and “colored” chromodynamic charges. Confinement in QCD.

The Unification of Forces

2018 ◽  
pp. 76-84
Author(s):  
Alvaro De Rújula
Keyword(s):  
Solar Neutrinos ◽  
Unified Theory ◽  
Grand Unified Theory ◽  
Radio Waves ◽  
Electromagnetic Interactions ◽  
Weak Neutral Currents ◽  
Vector Bosons ◽  
Heinrich Hertz ◽  
Fundamental Forces ◽  
Intermediate Vector

The quest for a unified theory of all fundamental forces. Faraday’s unification of all “types” of electricity. Maxwell’s unification of electricity, magnetism and light. Heinrich Hertz, and radio waves. The unification of weak and electromagnetic interactions by Glashow, Weinberg, and Salam. “Weak neutral currents.” The discovery of the “Intermediate Vector Bosons.” The quest for a “Grand Unified Theory.” Proton decay. The core of the Sun. Serendipity, solar neutrinos, and the supernova SN1987A. Neutrino oscillations. What a “gauge theory” is.

The Standard Theory

2017 ◽  
Author(s):  
John Iliopoulos
Keyword(s):  
Gauge Theory ◽  
Invariant Theory ◽  
Standard Theory ◽  
Strong Interactions ◽  
Gauge Invariant ◽  
Electromagnetic Interactions ◽  
Protons And Neutrons ◽  
Free Particles ◽  
Theoretical Predictions ◽  
Theory And Experiment

All ingredients of the previous chapters are combined in order to build a gauge invariant theory of the interactions among the elementary particles. We start with a unified model of the weak and the electromagnetic interactions. The gauge symmetry is spontaneously broken through the BEH mechanism and we identify the resulting BEH boson. Then we describe the theory known as quantum chromodynamics (QCD), a gauge theory of the strong interactions. We present the property of confinement which explains why the quarks and the gluons cannot be extracted out of the protons and neutrons to form free particles. The last section contains a comparison of the theoretical predictions based on this theory with the experimental results. The agreement between theory and experiment is spectacular.

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