In these lectures I give a short review of the main theoretical ideas underlying the extensions of the Standard Model of elementary particle interactions.

In this chapter a double tensor index k implies summation from 1 to 4. There is no classical way to treat the spin and charge variables of elementary particles. ' Therefore we represent matter by a set of complex wave fields p„. The quantities J, and S„& occurring in (1.1) are formed from matrices j„and s„A, . if I =0. Eq. (1.3) takes the form of Dirac's equation for a particle with inherent ma...

The mystery of the cosmological constant is probably the most pressing obstacle to significantly improving the models of elementary particle physics derived from string theory. The problem arises because in the standard framework of low energy physics, there appears to be no natural explanation for vanishing or extreme smallness of the vacuum energy, while on the other hand it is very difficult...

We propose a scalar background in Minkowski spacetime imparting constant proper acceleration to a classical particle. In contrast to the case of a constant electric field the proposed scalar potential does not create particle-antiparticle pairs. Therefore an elementary particle accelerated by such field is a more appropriate candidate for an " Unruh-detector " than a particle moving in a consta...

In recent years a new potential symmetry of fundamental particle physics has been investigated — discrete quark-lepton symmetry. When this symmetry is implemented, however, it often leads to either of the unrealistic predictions m u = m e or m d = m e. This paper considers two possible ways models based on m d = m e can be made realistic.

A concise introduction to the Standard Model of fundamental particle interactions is presented. e-mail address: guido.altarelli@cern.ch

In this paper we consider a few important questions concerning the microuniverse of elementary physical systems. We know leptonic matter is characterized by negative electric charge and leptonic antimatter by positive electric charge. Conversely baryonic matter is characterized by positive electric charge and baryonic antimatter by negative electric charge. In the Non-Standard Model both, matte...

According to astrophysical and cosmological observations, about 20 percent of the total energy in the universe is contributed by dark matter, which, within present observational limits, only exhibits gravitational interaction. Meanwhile, the Standard Model of elementary particles don’t contain such weakly-interacting constituents. To solve this mystery several schemes extending the Standard Mod...

In this article we have summarized the status of the system SANC version 0.41. We have implemented theoretical predictions for many high energy interactions of fundamental particles at the one-loop precision level for up to 4-particle processes. In the present part of our SANC description we place emphasis on an extensive discussion of an important first step of calculations of the one-loop amp...

We present an extended problem appropriate for students in a semester-long introductory elementary particle physics class. This problem requires them to synthesize concepts and investigative approaches learned throughout the class, directed toward answering the question of why muon-to-electron conversion experiments are proposed, but not electron-to-muon experiments. Although direct electron-to...