Accelerating Expansion: Philosophy and Physics with a Positive Cosmological Constant

Accelerating Expansion delves into the philosophical implications of modern cosmology, particularly the discovery of the Universe's accelerating expansion. It examines the nature of time, geometry, and physics in de Sitter worlds, discusses the limited extent of observation, and explores the problem of Boltzmann brains.

Format: Hardback
Length: 240 pages
Publication date: 24 August 2023
Publisher: Oxford University Press

Accelerating Expansion delves into the profound philosophical ramifications of contemporary cosmology, particularly emphasizing the profound impact of the discovery of the Universe's accelerating expansion on our comprehension of time, geometry, and physics. The inclusion of the cosmological constant in the equations of general relativity enables the modeling of universes characterized by an inherent tendency for spatial expansion. This constant, initially proposed by Einstein but later abandoned, regained prominence with the revelation of the accelerating expansion. This essay, designed with pedagogical intent, begins by examining the most fundamental and elegant relativistic world, characterized by a positive cosmological constant, de Sitter spacetime. It then explores the relatives of de Sitter spacetime that dominate modern relativistic cosmology. Some of the topics addressed include: the nature of time and simultaneity in de Sitter worlds; the remarkable dynamical attractor properties of de Sitter spacetime; the limitations of observation in revealing the topology of space in a world undergoing accelerated expansion; and cosmologists' perennial skepticism regarding the reliability of evidence and the possibility of knowledge, known as the problem of Boltzmann brains.

Weight: 430g
Dimension: 146 x 224 x 21 (mm)
ISBN-13: 9780192866462