Academic year2016/17
CoursePHYSICS
Code197BB
Credits9
PeriodSemester 2
LanguageItalian
| Modules | Area | Type | Hours | Teacher(s) |
| CROMODINAMICA QUANTISTICA | FIS/02 | LEZIONI | 54 | |
Programma non disponibile nella lingua selezionata
Knowledge
The student who successfully completes the course will be able to demonstrate a solid knowledge of the field theory known as Quantum Chromo-Dynamics (QCD).
He or she will acquire knowledge of the quark model, of the foundations of
non-Abelian gauge theories and of the basic results in perturbative QCD.
He or she will also acquire knowledge of the main nonperturbative aspects
of QCD, such as lattice QCD, instantons, 1/N expansion and chiral symmetries.
In particular, he or she will acquire a solid and detailed knowledge of the
problem of chiral symmetries of strong interactions, of their "spontaneous
breaking" (including the effects of the quantum anomaly in the so-called "U(1) problem"), and of the so-called "Chiral Effective Lagrangians".
Assessment criteria of knowledge
The student will be assessed on his/her demonstrated ability to discuss the main course contents using the appropriate terminology. Moreover, during the examination
the student will be required to present (as a written report) and discuss the solution of the problems assigned by the teacher during the course.
Methods:
- Final oral exam
- Written report
Teaching methods
Delivery: face to face
Learning activities:
- attending lectures
- preparation of oral/written report
- individual study
- Bibliography search
Attendance: Advised
Teaching methods:
- Lectures
- Task-based learning/problem-based learning/inquiry-based learning
Syllabus
A. FOUNDATIONS AND PERTURBATIVE METHODS IN QCD:
The "Eightfold Way" of Gell-Mann & Ne'eman, i.e., the SU(3) "flavour" symmetry.
The quark model of Gell-Mann & Zweig. The quantum number of "colour".
Gauge-invariance and Yang-Mills non-Abelian gauge theories. Quantum Chromo-Dynamics (QCD) as a non-Abelian gauge theory with SU(3) "colour" symmetry.
The quantization of gauge theories in the path-integral formalism. The Feynman rules for QCD. The "beta function" of Gell-Mann--Low and the "asymptotic freedom" of QCD. The "running coupling constant".
B. NON PERTURBATIVE METHODS IN QCD:
The Wilson formulation (in the Euclidean space) of "Lattice Gauge Theories". The problem of "confinament" and the Wilson criterion: the "string tension".
The chiral symmetries of strong interactions and their spontaneous breaking.
The method of "Effective Field Theories" and the so-called "Chiral Effective Lagrangians". The quark mass term and the masses of the pseudoscalar mesons.
The "U(1) problem" and the solution given by 'tHooft, Witten and Veneziano.
The limit of large number N of colours ("1/N expansion").
Instantons. The "theta" angle and the problem of strong P and CP violation.
Bibliography
Recommended reading includes the following works:
1) S. Weinberg, "The Quantum Theory of Fields, Volume I: Foundations;
Volume II: Modern Applications".
2) T.-P. Cheng & L.-F. Li, "Gauge Theory of Elementary Particle Physics".
3) T. Muta, "Foundations of Quantum Chromodynamics".
4) A. Smilga, "Lectures on Quantum Chromodynamics".
5) H. Georgi, "Weak Interactions and Modern Particle Theory".
Further bibliography for the most relevant original works appeared in the
specialized literature will be indicated during the course.
Updated: 14/11/2016 17:27
