
Course unit
ADVANCED TOPICS IN THE THEORY OF THE FUNDAMENTAL INTERACTIONS
SCP7081741, A.A. 2019/20
Information concerning the students who enrolled in A.Y. 2018/19
ECTS: details
Type 
ScientificDisciplinary Sector 
Credits allocated 
Educational activities in elective or integrative disciplines 
FIS/02 
Theoretical Physics, Mathematical Models and Methods 
6.0 
Course unit organization
Period 
First semester 
Year 
2nd Year 
Teaching method 
frontal 
Type of hours 
Credits 
Teaching hours 
Hours of Individual study 
Shifts 
Lecture 
6.0 
48 
102.0 
No turn 
Examination board
Board 
From 
To 
Members of the board 
2 ADVANCED TOPICS IN THE THEORY OF THE FUNDAMENTAL INTERACTIONS 
01/10/2019 
30/11/2020 
FERUGLIO
FERRUCCIO
(Presidente)
GIUSTO
STEFANO
(Membro Effettivo)
RIGOLIN
STEFANO
(Supplente)

1 ADVANCED TOPICS IN THE THEORY OF THE FUNDAMENTAL INTERACTIONS 
01/10/2018 
30/11/2019 
CASSANI
DAVIDE
(Presidente)
BELLAZZINI
BRANDO
(Membro Effettivo)
GIUSTO
STEFANO
(Membro Effettivo)
RIGOLIN
STEFANO
(Supplente)

Prerequisites:

A basic knowledge of theoretical physics of the fundamental interactions, in particular of
quantum field theory. 
Target skills and knowledge:

The course is focused on effective field theories (EFT), a general tool to describe
physical systems in the framework of a quantum field theory. We will proceed through explicit examples of the main ideas, focusing on those that are both pedagogical and relevant in physical systems that have been observed, or that are looked for, experimentally. 
Examination methods:

Discussion of selected topics from the program of the course, including resolution of problems. 
Assessment criteria:

Knowledge and understanding of the topics explained during the lectures and ability to solve related elementary problems. 
Course unit contents:

Part 1: INTRODUCTION AND EXAMPLES
 INTRODUCTION:
Characterization of a physical system:
degrees of freedom, relevant scale(s), symmetries.
 EXAMPLES OF EFT:
the Fermi theory of weak interactions;
derivation from the full electroweak theory.
beyond the treelevel: EulerHeisenberg Lagrangian;
symmetry considerations and derivation from QED.
 THE SM AS AN EFT:
recap of SM nonanomalous global symmetries;
dimension 5 operators, violation of (BL) and neutrino masses;
possible microscopic origin (seesaw mechanism).
dimension 6 operators, violation of B and proton decay;
possible microscopic origin (GUTs);
dimension 6 operators and flavour physics.
 EFT IN NONPERTURBATIVE REGIME:
the chiral Lagrangian; chiral symmetry breaking in QCD;
EFT for light pseudoscalar mesons; breaking effects;
anomaly of isoaxial current and neutral pion decay.
 OTHER EXAMPLES
Part 2: FORMAL ASPECTS
 EFT AND POWER COUNTING.
 INTEGRATING OUT HEAVY MODES:
RGE flow and matching conditions;
revisitation of the EulerHeisenberg Lagrangian;
other examples.
 APPELQUISTCARAZZONE DECOUPLING THEOREM.
 EQUIVALENT EFFECTIVE LAGRANGIANS;
independence of Smatrix elements on local field redefinitions.
 OPERATOR MIXING;
anomalous dimensions; examples;
 EFT DESCRIBING A BROKEN PHASE:
CCWZ construction; revisitation of the chiral Lagrangian;
other examples. 
Planned learning activities and teaching methods:

Blackboard lessons, discussion of examples, homework assignments. 
Additional notes about suggested reading:

A list of online lecture notes will be provided during the course. 
Textbooks (and optional supplementary readings) 

Innovative teaching methods: Teaching and learning strategies
 Lecturing
 Problem based learning
 Questioning
 Problem solving
 Loading of files and pages (web pages, Moodle, ...)

