Lectures were given at the Italian Society of Gravitational Physics Summer School "Relativistic Cosmology: Theory and Observation" in Como, Italy (May 2000); preprint no. RAP-290. astro-ph/0102402

Abstract: This set of lectures provides an overview of the basic theory and phenomenology of the cosmic microwave background. Topics include a brief historical review; the physics of temperature and polarization fluctuations; acoustic oscillations of the primordial plasma; the space of inflationary cosmological models; current and potential constraints on these models from the microwave background; and constraints on inflation. These lectures were given at the Italian Society of Gravitational Physics Summer School "Relativistic Cosmology: Theory and Observation" in Como, Italy (May 2000).

Table of Contents

• INTRODUCTION
• A BRIEF HISTORICAL PERSPECTIVE
• PHYSICS OF TEMPERATURE FLUCTUATIONS
• Causes of temperature fluctuations
• A formal description
• Tight coupling
• Free streaming
• Diffusion damping
• The resulting power spectrum
• PHYSICS OF POLARIZATION FLUCTUATIONS
• Stokes parameters
• Thomson scattering and the quadrupolar source
• Harmonic expansions and power spectra
• ACOUSTIC OSCILLATIONS
• An oscillator equation
• Initial conditions
• Coherent oscillations
• The effect of baryons
• COSMOLOGICAL MODELS AND CONSTRAINTS
• A space of models
• Physical quantities
• Power spectrum degeneracies
• Idealized experiments
• Current constraints and upcoming experiments
• MODEL-INDEPENDENT COSMOLOGICAL CONSTRAINTS
• Flatness
• Coherent acoustic oscillations
• Adiabatic primordial perturbations
• Gaussian primordial perturbations
• Tensor or vector perturbations
• Reionization redshift
• Magnetic Fields
• The topology of the universe
• FINALE: TESTING INFLATIONARY COSMOLOGY
• REFERENCES