Modern Cosmology

Citation

Dodelson, S., & Schmidt, F. (2025). Modern Cosmology (3rd ed.). Academic Press.

Chapter Summary

The third edition has 14 chapters in about 520 pages. The publisher describes a two-stage structure. It begins with the smooth, homogeneous universe described by a Friedmann–Lemaître–Robertson–Walker (FLRW) metric, with careful treatments of dark energy, big bang nucleosynthesis, recombination and dark matter. It then introduces perturbations about an FLRW universe: their evolution with the Einstein–Boltzmann equations, their primordial generation by inflation, and their observational consequences in the cosmic microwave background (CMB), gravitational lensing and galaxy clustering. The last chapter turns to the statistics of comparing models with data.

Chapters 1–4: The Concordance Model of Cosmology; The Expanding Universe; The Fundamental Equations of Cosmology; The Origin of Species

The smooth-universe part of the book. The opening chapter presents the concordance model, and the next chapters develop the expanding universe and the fundamental equations. The publisher's description lists dark energy, big bang nucleosynthesis, recombination and dark matter among the topics treated carefully in this part.

Chapters 5–6: The Inhomogeneous Universe: Matter & Radiation; The Inhomogeneous Universe: Gravity

The step from the smooth universe to perturbations. One chapter takes matter and radiation, the other gravity; together they lead to the Einstein–Boltzmann equations that the description names as the tool for evolving perturbations.

Chapters 7–8: Initial Conditions; Growth of Structure: Linear Theory

How the perturbations begin, which the description links to their primordial generation by inflation, and how they evolve in linear theory.

Chapters 9–10: The Cosmic Microwave Background; The Polarized CMB

The acoustic peaks of the CMB temperature spectrum, followed by polarization and its decomposition into E and B modes.

Chapters 11–13: Probes of Structure: Tracers; Growth of Structure: Beyond Linear Theory; Probes of Structure: Lensing

Tracers of structure (the description names the baryon acoustic oscillation ruler and redshift-space distortions in galaxy clustering), growth of structure beyond linear theory, and gravitational lensing of the CMB and of large-scale structure.

Chapter 14: Analysis and Inference

The closing chapter on how cosmological data are analysed and parameters inferred; the publisher mentions a new section on emergent analysis techniques in this edition.

Key Concepts

• Concordance model and FLRW universe: the standard picture and its smooth background (Chapters 1–3).
• Dark energy, nucleosynthesis, recombination and dark matter: the main components and episodes of the background universe, as listed in the publisher's description (Chapters 1–4).
• Einstein–Boltzmann equations: the coupled equations that evolve perturbations (Chapters 5–6).
• Initial conditions from inflation: the primordial seeds of structure (Chapter 7).
• Linear growth of structure: perturbation evolution while it is small (Chapter 8).
• CMB acoustic peaks and E/B polarization: the central CMB observables (Chapters 9–10).
• BAO standard ruler and redshift-space distortions: probes in galaxy clustering (Chapter 11).
• Gravitational lensing: of the CMB and large-scale structure (Chapter 13).
• Statistical inference: parameter estimation from data (Chapter 14).

Critical Analysis

Strengths

• A full path from background to data. The chapter order moves from the expanding universe through perturbation theory to the CMB, large-scale structure, lensing and inference, which shows how theory connects to measurement.
• Practical orientation. Elsevier's key features describe a practical approach to learning how to perform cosmological calculations.
• Updated for recent developments. The third edition adds material on gravitational waves, line intensity mapping and emergent analysis techniques, expands the sections on CMB secondaries, adds material on theory, simulations and analysis of nonlinear structures, and revises figures and pedagogy.
• Authors active in the field. The authors work on the CMB, large-scale structure, dark energy and nonlinear structure formation, which corresponds to the book's emphasis.

Limitations

• Graduate-level and specialised. The publisher names physics graduate students in cosmology courses and researchers as the readership; the contents have no introductory astronomy or general-relativity primer.
• Focus on perturbations and observables. Most of the 14 chapters concern inhomogeneities, the CMB and large-scale structure; broader topics in astrophysics such as stars and galaxies appear in the contents only through structure and tracers.
• Substantial assumed background. The site lists general relativity or cosmology, statistical mechanics, quantum mechanics and Fourier methods as prerequisites, so the book is not suited to a first encounter with the subject.

Where It Fits in the Course

Dodelson and Schmidt is the graduate cosmology text in the astrophysics and cosmology list. The other books lead up to it. Fraknoi, Morrison and Wolff's Astronomy 2e is a largely non-mathematical introduction to the whole universe, and Binney's Astrophysics: A Very Short Introduction concentrates on the physical processes at work in astronomical objects. Carroll and Ostlie's An Introduction to Modern Astrophysics is a comprehensive calculus-based survey ending with cosmology, and Maoz's Astrophysics in a Nutshell is a concise one-semester course with cosmology as its final topic. Liddle's An Introduction to Modern Cosmology is the short undergraduate route into Big Bang cosmology, deriving the expansion and thermal history with Newtonian arguments where they suffice.

The natural sequence for a student aiming at research cosmology is an undergraduate treatment such as Liddle, then Dodelson and Schmidt for perturbation theory and observables.

How to Use This Book

The book is for physics graduate students and researchers who have undergraduate general relativity or cosmology, statistical mechanics and quantum mechanics, and who are comfortable with Fourier methods.

A practical plan: use Chapters 1–3 to establish the background, treating them as review if an undergraduate cosmology course has been taken. Chapters 5–8 are the technical core: the Einstein–Boltzmann equations, initial conditions and linear growth. The CMB chapters (9–10) and the large-scale-structure chapters (11–13) can then be taken in either order depending on the course emphasis. Chapter 14 suits readers who will work with data. Because the book teaches cosmological calculations, work through the derivations by hand rather than reading them passively.