The title of the course can be in fact considered fluctuating; if it goes well enough, I would probably change the title to “Diagrammatic methods in the theory of cosmological perturbations”. In this case, topics signed by * in the program will be discussed in more details.

Lectures: Fridays, 10-12 (Physicum, A315); please note that I will be away from Jan 27 till Feb 5, and there will be no lectures and seminars during that week.

Seminars: Wednesdays, 15-16 (Physicum, A315); first seminar is on Jan 23.

Recommended (but not required) background: Cosmology I and II, general relativity, CMB physics, diagrammatic methods in QFT. 

Lectures: program

Lecture 1: Introduction - the Large Scale Structure of the Universe. Newtonian linear perturbation theory. Linear perturbations in the presence of expansion. Adiabatic and entropy perturbations. Jeans length.

Lecture 2: Perturbation theory in general relativity I: scalar, vector and tensor perturbations in GR, gauge transformations.

Lecture 3: Inflation: reminder.

Lecture 4: QFT in de Sitter space, quantization of inflationary perturbations, generation of cosmological perturbations during inflation.

Lecture 5: Non-gaussianities from inflation: introduction. 3-point function, equilateral and squeezed limits.

Lecture 6: Eternal inflation - stochastic approach. Langevin and Fokker-Planck equations.

Seminars: program

Seminar 1. Zel'dovich approximation. Crocce-Scoccimarro LSS diagrammar.*

Seminar 2. Cosmological perturbations in the presence of hydrodynamic matter.

Seminar 3. Inflationary RG flow. Cosmological perturbations in the universe filled with a scalar field

Seminar 4. QFT in de Sitter space. Spectrum of inflationary perturbations. Rindler universe: thermal radiation from horizon

Seminar 5. δN formalism at tree level. Byrnes-Koyama-Sasaki-Wands diagrammar for non-gaussianities.