FSI3330 Thermal Field Theory 7.5 credits

Part I:

• Introduction. General concepts of statistical physics and quantum field theory
• Quantization of the bosonic field at finite temperature; Matsubara frequencies; Feynman rules at finite temperature
• Quantization of the fermionic field at finite temperature; fermionic path integrals and coherent state formalism
• Quantization of the gauge fields at finite temperature; ghosts and blackbody radiation; static screening
• Renormalization and infrared problems
• Collective excitations in a plasma
• Equivalence of real-time and imaginary-time formalism

Part II:

• Linear response theory
• Resummation and effective actions; Daisy diagrams
• Hard thermal loop expansion
• Dynamical screening

Part III:

• Spontaneous symmetry breaking and restoration
• Phase transitions and inflation
• Transport equations and baryogenesis; Kadanoff-Baym equations in Wigner space

Upon passing the course the student should:

• Be able to recount how a finite temperature and density background affects field theoretical computations.
• Treat bosonic and fermionic systems and quantization within thermal field theory.
• Be able to use thermal field theory to describe spontaneous symmetry breaking at finite temperature.

The course is mainly intended to graduate students with interest in theoretical physics and cosmology. Basic knowledge in statistical mechanics and quantum field theory are prerequesites.

• M. Le Bellac, Thermal field theory, Cambridge University Press, 1996
• J. I. Kapusta, Finite-temperature field theory, Cambridge University Press, 1989

If the course is discontinued, students may request to be examined during the following two academic years.

• INL1 - Assignment, 7.5 credits, grading scale: P, F

Based on recommendation from KTH’s coordinator for disabilities, the examiner will decide how to adapt an examination for students with documented disability.

The examiner may apply another examination format when re-examining individual students.

Hand in assignments.

Tommy Ohlsson

• All members of a group are responsible for the group's work.
• In any assessment, every student shall honestly disclose any help received and sources used.
• In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.