The Standard Model and Beyond

This paper provides a brief overview for non-specialists of some of the highlights in the development of the theory of weak interactions during the past century.

Review of recent developments in attempts to go beyond the Standard Model is given. We concentrate on three main unresolved problems: mechanism of electroweak symmetry breaking, expected new physics at the TeV scale (mainly SUSY) and the origin of the Dark matter.

The Standard Model (SM) of particle physics is in such good agreement with experiment that it is currently accepted as providing an accurate model of reality, with the role of chiral symmetry breaking in electro-weak unification regarded as one of its major achievements. This work focusses on weaknesses in the algebraic formulation of the SM, especially the introduction of chirality, which is shown to be inconsistent with neutrinos being fermions, and conflicts with the exper...

Studies in nuclear and atomic physics have played an important role in developing our understanding of the Standard Model of electroweak interactions. We review the basic ingredients of the Standard Model, and discuss some key nuclear and atomic physics experiments used in testing these ideas. We also summarize the conceptual issues of the Standard Model that motivate the search for new physics.

In these lectures I describe some of the open questions in the standard model relating to the nature and origin of mass, forces and matter and discuss some of the speculative theoretical ideas put forth in this regard. Some of the topics touched upon include supsersymmetry, dynamical symmetry breaking, composite models, grand unified theories and superstrings.

The results of high precision weak neutral current (WNC), Z-pole, and high energy collider electroweak experiments have been the primary prediction and test of electroweak unification. The electroweak program is briefly reviewed from a historical perspective. The current status and the implications for the standard model and beyond are discussed.

I discuss some new trends in particle theory beyond the standard model. Some topics briefly covered include elecroweak baryogenesis, gauge versus non-gauge discrete symmetries, the strong CP problem, dynamical symmetry breaking scenarios, supersymmetric grand unification, new aspects in low energy supersymmetry and superstring phenomenology.

We present a concise review of the status of the Standard Model and of the search for new physics.

We review the experimental and theoretical status of the standard electroweak theory, and its fundamental parameters. We obtain the global best fit result for the Standard Model Higgs boson of M_H = 107^{+67}_{-45} GeV, and find the 95% upper limit of 255 GeV. Parameters describing physics beyond the Standard Model are discussed as well. Particular emphasis is given to implications for supersymmetric extensions of the Standard Model.

Without going to the details, I give a short, qualitative and historical description of the development of the Standard Model, from quantum electrodynamics, further through quantum chromodynamics, then to weak interactions with parity- and CP-violation, ending up with electroweak symmetry breaking and the Higgs boson. The presentation is based on my own experiences from the late 1960's up to the discovery of the Higgs boson. It is mainly meant for students at master level, an...