# PHYSICS OF FUNDAMENTAL INTERACTIONS

## Learning outcomes of the course unit

The course has as its main objective the training to present the theoretical formulation and the main phenomenological implications of the physics of fundamental interactions between elementary entities and to make both the theoretical formulation and the main phenomenological implications familiar to the student giving him the capacity of handling both the concepts and giving him the technical ability of mastering the related calculations.

In particular in a list of progressive comprehention goals it is planned to present and discuss:

A basic treatment of the electroweak interaction and of the strong interaction with particular reference to:

The discussion of the fundamental aspects of the theories, their formulation and internal consistency.

The ability to describe phenomena in the formalism of the relativistic quantum field theory.

The ability to calculate physical quantities.

The comparison of the theoretical evaluations with the results of experiments. A main training goal is to give to the student the capacity of discussing and commenting critically the arguments. This goal will be pursued by lecturing critically always interacting with the students.

In particular the student should be able to:

1. Possess the basic concepts of the modern formulation of the theories of the fundamental interactions.

2. Have a knowledge of their limits of applicability and master the possible phenomenological applications.

3. Be able to present with sufficient technical competence results and implications also to non experts.

4. Be able to evaluate when faced with a new problem or case related to the concepts and themes already discussed in the course, to determine which would be the more appropriate way to solve it.

5. Establish links between the various topics discussed in the course being able to highlight similarities and differences by having acquired adequate learning skills.

## Prerequisites

As a prerequisite it is demanded a basic knowledge of the relativistic quantum field theory as well as of the relativistic kinematics.

## Course contents summary

Introduction: Quantum ElectroDynamics

The Lagrangian formulation of Quantum Electrodynamics

The 'Weak Interaction - The Fermi Theory of Beta Decay

The parity violation in weak interactions

The hypothesis of the intermediate bosons

The theory of Glashow-Weinberg-Salam

The renormalization of the Electroweak Theory

The Strong Interaction

The quark model and the parton model

The Lagrangian of Quantum Chromodynamics

The asymptotic freedom and confinement

The perturbative approach to Quantum Chromodynamics

The mechanism of Brout Englert Higgs and the masses of the intermediate bosons

The Standard Model of Fundamental Interactions SU(3)xSU(2)xU(1)

## Course contents

Introduction: Quantum ElectroDynamics

The Lagrangian formulation of Quantum Electrodynamics

The 'Weak Interaction - The Fermi Theory of Beta Decay

The parity violation in weak interactions

The hypothesis of the intermediate bosons

The theory of Glashow-Weinberg-Salam

The renormalization of the Electroweak Theory

The Strong Interaction

The quark model and the parton model

The Lagrangian of Quantum Chromodynamics

The asymptotic freedom and confinement

The perturbative approach to Quantum Chromodynamics

The mechanism of Brout Englert Higgs and the masses of the intermediate bosons

The Standard Model of Fundamental Interactions SU(3)xSU(2)xU(1)

## Recommended readings

Advanced Quantum Mechanics J. J. Sakurai

The Quantum Vacuum - An Introduction to QED P. W. Milonni

Dynamics of the Standard Model J.F. Donogue, E. Golowich, B. L. Holstein

## Teaching methods

Lectures, exercises.

During lectures a series of excercises will be presented as explicit examples of complete evaluations of physics quantities.

As home works the studet will individually consider analogous or related evaluations in order to apply concepts and tecniques already discussed.

Relative results will be discussed in the susequent lectures together with the related physical implications.

Some of the main scientific papers concerning the themes of the course will be object of detailed and critical discussion.

## Assessment methods and criteria

In order to pass the final exam the student will be required:

a sufficiently adequate understanding of the main aspects of the physics of fundamental interactions.

a sufficient familiarity with the main formal tools and the ability to understand the derivation and calculation of the main physical observables.

The ability to read and understand scientific articles on the most important topics of the course.

The summary assessment of the learning is carried out through a final written exam:

The written examination, which lasts 2 hours, consists of 3 open questions (each for the

Score ranges from 0 to 10)

The student must demonstrate that he has understood, and is able to apply, the fundamental concepts of

Every topic discussed.

Exam results are published on the Esse3 portal within one week of the examination date. The students

They can view the exam, after appointment with the teacher.