Syllabus
* Basic cosmological models
Reminders from the General theory of relativity course (NTMF111): basic cosmological observations (distribution of matter in the universe, cosmic structures, large-scale homogeneity and isotropy), Olbers' paradox, cosmic expansion, big bang, CMBR; cosmological principle, spaces of constant curvature, FLRW metric; matter and radiation as “cosmic fluid”, evolution of their density; Friedmann equation, inventory of possible cosmic evolutions, role of matter, radiation, spatial curvature and cosmological constant; language of Omega-factors and current “concordance” parameter values. Geodesics, properties of the cosmic-fluid congruence; cosmological redshift; standard candles, cosmological distances (luminosity and angular-diameter distance), redshift-distance relation; cosmological particle and event horizons. Dynamics of expansion, cosmological evolution of crucial quantities. Dark matter, dark energy, problems of FLRW models.
* Early universe
Thermal history of the universe; nucleosynthesis, baryon-to-photon ratio, baryon asymmetry, cosmic baryogenesis, Sakharov’s conditions, washout, baryogenesis in the Standard Model of particle interactions (baryon number violation, CP violation, instantons and sphalerons, problems of weak-scale baryogenesis), baryon-to-lepton number transitions, leptogenesis in the Standard Model with massive neutrinos, Davidson-Ibarra limit, grand unification.
* Very early universe: Cosmic inflation
Shortcomings of the standard model of cosmology, introduction of the idea of inflationary expansion. Scalar field as a model for inflationary behaviour, Guth’s inflation, additional inflationary models based on scalar fields (connection with GUT and early universe); phase transitions, bubble dynamics, (classical) evolution of scalar field’s quantum fluctuations and metric fluctuations. Observational signatures of inflation, alternative realizations of inflation.
* Fluctuations, perturbations and structure growth
Perturbative treatment of matter clustering (connection with basic cosmology), definition of metric perturbations, derivation of Jeans’ criteria and description of linear collapse, gauge problem in relativistic perturbations, Bardeen’s approach to gauge invariant perturbations, basic ideas of covariant perturbations, non-linear perturbations and structure growth (basic ideas).
* Cosmic microwave background radiation
Detailed description of the matter era (dust and radiation), origin of CMB radiation, multifluid perturbation theory, characterization of the primary anisotropies (acoustic oscillations, Silk damping), secondary anisotropies (gravitational lensing, Sachs-Wolfe effect, Sunyaev-Zel'dovich effect), polarization (E modes and B modes), CMB spectrum features and its significance, CMB fast algorithm, CAMB algorithm.
* Dark sides of the universe
Dark energy, dark matter - basic observations, cosmological constant, time dependent cosmological constant and quintessence, X-essence, current models of dark energy (inhomogeneous universe and averaging, modified gravity). Dark matter distribution from weak lensing and from cosmic shear, observational constraints on dark matter and dark-energy models.
* Dark ages, new enlightenment and structure formation
Dark ages, atoms, molecules, stars, galaxies: structure-formation models and simulations. Large-scale structure of the universe. Baryon acoustic oscillations.
* Final destiny of the universe
Very-long-range forecasts…
Annotation
Second semester of a modern theoretical-cosmology course. Basic cosmological models; early universe and cosmic inflation; fluctuations, perturbations and structure growth; gravitational lensing; dark matter; cosmic microwave background radiation and its anisotropies.
Mainly for master and PhD students of theoretical physics, nuclear and particle physics and astrophysics. Knowledge of general relativity and quantum field theory is assumed at the level of NTMF111 and NJSF068 courses.
The course is taught in English.