TASI Lectures on Inflation

TL;DR

This paper provides a comprehensive pedagogical review of cosmological inflation, covering its theoretical foundations, quantum fluctuations, and observational comparisons, aimed at advanced students and early researchers.

Contribution

It offers an accessible, structured overview of inflationary theory, including recent observational constraints and future directions, tailored for learners with basic physics backgrounds.

Findings

Inflation solves horizon and flatness problems.

Primordial fluctuations are generated during inflation.

WMAP data constrains inflationary models.

Abstract

This series of lectures gives a pedagogical review of the subject of cosmological inflation. I discuss Friedmann-Robertson-Walker cosmology and the horizon and flatness problems of the standard hot Big Bang, and introduce inflation as a solution to those problems, focusing on the simple scenario of inflation from a single scalar field. I discuss quantum modes in inflation and the generation of primordial tensor and scalar fluctuations. Finally, I provide comparison of inflationary models to the WMAP satellite measurement of the Cosmic Microwave Background, and briefly discuss future directions for inflationary physics. The majority of the lectures should be accessible to advanced undergraduates or beginning graduate students with only a background in Special Relativity, although familiarity with General Relativity and quantum field theory will be helpful for the more technical sections.