The Role of Symmetry Breaking in the Standard Model of Particle Physics

Author(s): Dr. KM Nirupma Kumari

Abstract:

This paper investigates the fundamental role of Spontaneous Symmetry Breaking (SSB) in the Standard Model (SM) of Particle Physics. The SM is constructed upon the principle of local gauge symmetry, which inherently requires all force carriers and matter particles to be massless, a prediction that fundamentally contradicts experimental evidence. The core objective of this study is to meticulously detail the theoretical mechanism by which the masses of the W and Z gauge bosons and all fundamental fermions are generated. We demonstrate that the Higgs mechanism, a process involving a complex scalar field acquiring a non-zero vacuum expectation value (v), spontaneously breaks the electroweak symmetry SU(2)L × U(1)Y down to the electromagnetic U(1)em.This breaking is shown to provide the longitudinal polarization (and hence mass) to the weak force carriers via the Brout-Englert-Higgs mechanism and, through the Yukawa coupling, imparts mass to the fundamental fermions. The successful prediction and subsequent 2012 discovery of the remnant excitation of this field, the Higgs boson, serves as the definitive experimental validation for the SSB paradigm as the cornerstone of mass generation within the Standard Model.

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Pages: 09-14     |    3 View     |    0 Download