Physics of the Cosmic Microwave Background and the Planck Mission

TL;DR

This paper reviews the physics behind the cosmic microwave background anisotropies, their origins from primordial perturbations, and discusses the Planck satellite's mission to observe these phenomena.

Contribution

It provides a comprehensive overview of the physical processes causing CMB anisotropies and details the objectives and methods of the Planck satellite mission.

Findings

Identification of four main contributions to anisotropy

Explanation of primordial perturbations from quantum fluctuations

Description of Planck mission's observational goals

Abstract

This lecture is a sketch of the physics of the cosmic microwave background. The observed anisotropy can be divided into four main contributions: variations in the temperature and gravitational potential of the primordial plasma, Doppler effect from its motion, and a net red/blueshift the photons accumulate from traveling through evolving gravitational potentials on their way from the primordial plasma to here. These variations are due to primordial perturbations, probably caused by quantum fluctuations in the very early universe. The ongoing Planck satellite mission to observe the cosmic microwave background is also described.