Thermal Field Theory



Related summer school lectures, from 2010, in slide format .

Lecturer: Mikko Laine
Time: Tue 10-12, Thu 12-14, starting 16.10.2007.
Place: D6-135.
Background: Quantum field theory / statistical physics.
Literature: * C. Gale and J.I. Kapusta, Finite-Temperature Field Theory.
* M. Le Bellac, Thermal Field Theory.
Schedule: Contents.
16.10.: Quantum mechanics. Partition function Z. Path integral for Z.
18.10.: No lecture.
23.10.: Evaluation of Z for harmonic oscillator. Exercise 1 & solution.
25.10.: Free scalar fields. Path integral for Z. Fourier representation.
30.10.: Evaluation of thermal sums. Exercise 2 & solution. Low-T expansion.
01.11.: No lecture.
06.11.: High-T expansion. Gamma and zeta functions. Exercise 3 & solution.
08.11.: Interactions. Weak coupling expansion. Wick theorem. Propagator.
13.11.: Z naively to order lambda & lambda**2. Exercise 4 & solution.
15.11.: UV renormalisation. Z properly to order lambda.
20.11.: IR resummation. Z properly to order lambda**3/2. Exercise 5 & solution.
22.11.: Path integral for Z of fermionic harmonic oscillator.
27.11.: The Dirac field at finite T. Fermionic sums. Exercise 6 & solution.
29.11.: Gauge fields. Path integral for Z.
04.12.: No lecture.
06.12.: Gauge fixing, ghosts. Feynman rules. Exercise 7 & solution.
11.12.: Thermal gluon mass.
13.12.: Z to order g**3. Exercise 8 & solution.
18.12.: The IR problem at finite T. Low-energy effective field theories.
20.12.: Dimensional reduction of QCD. Exercise 9 & solution.
08.01.: Finite density. Complex scalar field. Effective potential; BEC.
10.01.: Dirac fermion. Chemical potentials and gauge symmetry. Exercise 10 & solution.
15.01.: Real-time observables. Different Green's functions.
17.01.: From Euclidean correlator to spectral function. Exercise 11 & solution.
22.01.: Hard Thermal Loops.
24.01.: Relation to classical kinetic theory. Exercise 12 & solution.
29.01.: Thermal phase transitions.
31.01.: Bubble nucleation rate. Exercise 13 & solution.
Particle production rate.
05.02.: Dark matter abundance in cosmology.
07.02.: Transport coefficients.
Further reading.
As a reference: Old version.