PHYSICS OF COMPLEX SYSTEMS
cod. 1001046

Academic year 2010/11
1° year of course - First semester
Professor
Academic discipline
Fisica teorica, modelli e metodi matematici (FIS/02)
Field
Teorico e dei fondamenti della fisica
Type of training activity
Characterising
48 hours
of face-to-face activities
6 credits
hub:
course unit
in - - -

Learning objectives

The course will be devoted to the conceptual and quantitative study of several systems featuring complex behavior, in the physics of matter, in graphs and network theory, in biological systems, in computer science and in other interdisciplinary applications. We will consider several aspects of the most advanced theoretical approaches and of their application, providing the basis for theoretical modelling and for the application of methods in statistical mechanics and in dynamics to the study of complex systems.

Prerequisites

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Course unit content

Advanced methods in statistical mechanics for complex systems, in physics and in interdisciplinary domains.

Full programme

- Advanced methods in statistical mechanics for complex systems: singularities, phase transitions and ergodicity breaking. Systems at a critical point, scaling and universality. Order parameters and spontaneous symmetry breaking. Mean field, Laundau-Ginzburg theory. Critical dimensions. Static and dynamical scaling. Spin models. Variational methods for free energies.

- The effects of disorder: Harris criterion, Griffith singularities. Spin glasses, SK model and p-spin modes. Random fields models, supersymmetry and dimensional reduction. Spin models and optimization problems, phase transitions in complexity classes. Polymers in equilibrium. Percolation.

- Dynamics: stochastic differential equations and supersymmetric models. Asymptotic out of equilibrium regimes. Growth models, coarsening. KPZ equation for surface growth. Polimers, statics and dynamics. Fluctuation dissipation theorem and its estension.

- Complex networks: graph theory, topological characterization of graphs and complex networks. Spectral properties on finite and infinite graphs. Statistical models and diffusion on graphs. Syncronization. Biological networks: neural networks, immune networks. Harmonic oscillations and normal modes in proteins.

- Quantum phase transitions: an introduction.

Bibliography

Chapters from the following books:
G. Parisi, Statistical Field Theory, Addison-Wesley (1988)
N. Goldenfeld, Lectures On Phase Transitions And The Renormalization Group Frontiers in physics (1992)
J. P. Sethna, Statistical Mechanics: Entropy, Order Parameters, and Complexity, Oxford University Press (2007)
Course Material and Articles

Teaching methods

Oral and practical lessons

Assessment methods and criteria

Oral exam

Other information

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