A. Solomon – Cosmology Beyond Einstein (2017)

Автор: A. Solomon
Название книги: Cosmology Beyond Einstein (2017)
Формат: PDF
Жанр: Физика
Страницы: 239
Качество: Изначально компьютерное, E-book

This work investigates the theoretical and cosmological implications of modifying Einstein's theory of general relativity. It explores two classes of modifications to gravity: those in which the graviton is given a small mass, and those in which Lorentz invariance is spontaneously broken. It elucidates the nature of cosmological perturbations in theories of massive bimetric gravity, including a potentially deadly instability. Theories of gravity beyond general relativity could explain why the expansion of the Universe is accelerating, obviating the need for a dark energy, and can also affect the evolution of the early Universe. Next, it investigates the nature of spacetime in massive gravity theories that contain two different spacetime metrics. Lastly, the strongest constraints to date are placed on the size of Lorentz-violating effects in the gravity sector during inflation.
Contents:
Introduction
Gravity Beyond General Relativity
Cosmological Stability of Massive Bigravity
Linear Structure Growth in Massive Bigravity
The Geometry of Doubly-Coupled Bigravity
Cosmological Implications of Doubly-Coupled Massive Bigravity
Cosmological Implications of Doubly-Coupled Massive Gravity
Lorentz Violation During Inflation
Discussion and Conclusions