Includes bibliographical references and index.

Machine generated contents note: 1. Overview; 2. Expansion history of the universe; 3. Correlation function and power spectrum; 4. Basics of cosmological perturbation theory; 5. Observational evidence of dark energy; 6. Cosmological constant; 7. Dark energy as a modified form of matter I: quintessence; 8. Dark energy as a modified form of matter II; 9. Dark energy as a modification of gravity; 10. Cosmic acceleration without dark energy; 11. Dark energy and linear cosmological perturbations; 12. Non-linear cosmological perturbations; 13. Statistical methods in cosmology; 14. Future observational constraints on the nature of dark energy; 15. Conclusion and outlook; 16. Answers to the problems; 17. Mathematical appendix; Index.

"Dark energy, the mysterious cause of the accelerating expansion of the Universe, is one of the most important fields of research in astrophysics and cosmology today. Introducing the theoretical ideas, observational methods and results, this textbook is ideally suited to graduate courses on dark energy, and will also supplement advanced cosmology courses. Providing a thorough introduction to this exciting field, the textbook covers the cosmological constant, quintessence, k-essence, perfect fluid models, extradimensional models, and modified gravity. Observational research is reviewed, from the cosmic microwave background to baryon acoustic oscillations, weak lensing, and cluster abundances. Every chapter ends with problems, with full solutions provided, and any calculations are worked through step-by-step. "--