Advanced Statistical Physics

 

Lectures: Johannes Berg
Exercise classes: Arman Angaji


Statistical physics describes systems with many interacting degrees of freedom. Tools and concepts of statistical physics have applications
in condensed matter physics, but also far beyond the traditional realm of physics, for instance in the modelling of biological, economic,
or social systems. This lecture course covers the basic tools of modern statistical physics, as well as the required mathematical apparatus.
A key concept to address fluctuations on different length-scales is the so-called renormalisation group, which emerges as the shared language
between quantum field theory, condensed matter physics, statistical physics, and even cosmology. Particular topics are
This lecture course is part of the Master course in physics.

Schedule

Lectures are on Tuesdays 8:00-09:30 and Thursdays 10:00-11:30 in lecture theater III; the course will start on 11.11. All lectures will also be recorded.

Registration: If you are going to take this class for credit (this is most of you), please sign up on KLIPS2.0. Registering should automatically give you access to the relevant ILIAS page. Otherwise, connect to this ILIAS page and sign up for membership. Use the rider "Sprache" (language) on the top right to set the language to English. Let me know via email if there are technical problems or if you have questions.

There will be weekly tutorial classes, both in person and online. Registration will be via the Ilias page.

Exams: 9.2.2023, 12:00 - 15:00
Retake: 22.3.2021, 9:00 -12:00
Both exams will be in Lecture Theatre 1.

Resources and teaching materials

The central resource for lectures and problem sets is the ILIAS page here. There is also a discussion board where you can ask and answer questions.

Below, I will place Mathematica notebooks on some analytically solvable models addressed in this course, as well as links to applets
and other material of interest. To view the results you can use the free Wolfram CDF Player (500Mb, sorry!). To explore the solutions
further on your own, you can use the Mathematica notebooks (.nb) on the computers in the CIP-lab, which run Mathematica.

Ising model in 1D .cdf .nb .pdf
Ising model in 2D .cdf .nb .pdf
Weiss' model of the ferromagnet .cdf .nb .pdf

There are many applets simulating the 2D-Ising model. This one here lets you change both the temperature and the magnetic field (try it!).
Dominik Derigs (thanks!) has produced an animation of the free energy function of the Curie-Weiss (mean field) ferromagnet, available here.
Watch the parameters beta and h in the bottom right corner.
A handout covering the RG analysis of the Landau-Ginzburg action for the coupling parameter g is available here.


Literature

N. Goldenfeld, Lectures on phase transitions and the renormalization group, Westview Press
N.G. van Kampen, Stochastic Processes in Physics and Chemistry, North Holland
M. Kardar, Statistical Physics of Fields, Cambridge University Press
M. Plischke and B. Bergersen, Equilibrium Statistical Physics, World Scientific
(in German) H. Römer and T. Fink, Statistische Mechanik, VCH

The best single book to start with is Kardar. This is the second volume of two. You may also want to look at the first volume
(Statistical Physics of Particles) to refresh your knowledge of elementary statistical physics. The topics of scaling and renormalisation are covered optimally in Goldenfeld.






Picture credit: Mietitor17, see here for details and licensing.