Bangs, Crunches, Whimpers, and Shrieks: Singularities and Acausalities in Relativistic SpacetimesAlmost from its inception, Einstein's general theory of relativity was known to sanction spacetime models harboring singularities. Until the 1960s, however, spacetime singularities were thought to be artifacts of the idealizations of the models. This attitude evaporated in the face of a series of theorems, due largely to Stephen Hawking and Roger Penrose, which showed that Einstein's general theory implies that singularities can be expected to occur in a wide variety of conditions in both gravitational collapse and in cosmology. In the light of these results some physicists adopted the attitude that, since spacetime singularities are intolerable, general relativity contains within itself the seeds of its own destruction. Others hoped that peaceful coexistence with singularities could be achieved by proving a form of Roger Penrose's cosmic censorship hypothesis, which would place singularities safely inside black holes. Whatever the attitude one adopts toward spacetime singularities, it is evident that they raise a number of foundational problems for physics and have profound implications for the philosophy of space and time. However, philosophers of science have been slow to awaken to the significance of these developments. Indeed, this is the first serious book-length study of the subject by a philosopher of science. It features an overview of the literature on singularities, as well as an analytic commentary on their significance to a number of scientific and philosophical issues. |
Contents
3 | |
2 Defining Characterizing and Proving the Existence of Spacetime Singularities | 27 |
3 Cosmic Censorship | 64 |
4 Supertasks | 103 |
5 The Big Bang and the Horizon Problem | 124 |
6 Time Travel | 160 |
Other editions - View all
Bangs, Crunches, Whimpers, and Shrieks: Singularities and Acausalities in ... John Earman Limited preview - 1995 |
Common terms and phrases
b-incomplete big bang big bang model black hole Cauchy surface chapter chronology chronology-violating classical GTR closed timelike curves common cause compact conjecture consistency constraints coordinate cosmic censorship cosmic censorship hypothesis cosmological models counterexample CTCs curvature singularities definition discussion Einstein Einstein's field equations energy condition entails example existence extension finite future geodesic incompleteness Geroch globally hyperbolic Gödel spacetime Gödelian time travel grandfather paradox gravitational collapse gravitational field half-curve Hawking and Ellis horizon problem hypersurface infinite infinity initial conditions initial data laws M-H spacetimes machine matter maximal metric Minkowski spacetime naked singularities null geodesics observer partial Cauchy surface particle horizons Penrose philosophical Physical Review physically possible predictability quantum gravity relativistic spacetimes result scalar Schwarzschild sense signal slices solutions to EFE space spacelike spacetime singularities spatially standard big bang structure supertasks tensor theorem theory timelike geodesic topology violation Wald world line wormhole y₁