# General Relativity and Cosmology

*20 credits / 30 lectures per semester*

1st semester (Theoretical Cosmology):

- What is cosmology? (And what is it not?)
- The background Universe: kinematics and dynamics in the expanding Friedmann spacetime (metric, lightcones, distances, 4-velocity, 4-wave vector, redshift, energy-momentum tensor, hot Big Bang model, Dark Energy, Inflation)
- Cosmological perturbation theory: basics (overview of how fluctuations originate and then grow to generate the cosmic microwave background (CMB) anisotropies and galaxies; perturbations in density, velocity and metric potentials)
- The perturbed Einstein field equations: the evolution of density, velocity and curvature perturbations in the radiation, matter and Dark Energy eras (how modes evolve from Inflation; transfer functions; the effect of Dark Energy; analytical and numerical solutions)
- The galaxy correlation function and power spectrum (galaxy bias; galaxy number counts and variance; evolution of the power spectrum in the matter and Dark Energy eras)
- Probing the expansion history and the growth of large-scale structure via galaxy surveys (the BAO feature in the galaxy power spectrum; the growth rate from RSD in the galaxy power spectrum)

2nd semester (Modern Cosmological Physics):

This module will cover many areas of active research today. Specific topics to be covered:

- Black holes
- Gravitational waves
- Early universe physics
- Particle astrophysics

Prerequisites:

The undergraduate module 3GR (General Relativity), or equivalent, is required.