The Renaissance of General Relativity and Cosmology Book contents
- Frontmatter
- Contents
- Author Addresses
- 1 Introduction
- 2 Exact and inexact solutions of the Einstein field equations
- 3 Inertial forces in general relativity
- 4 Relativistic radiation hydrodynamics: a covariant theory of flux-limiters
- 5 Relativistic gravitational collapse
- 6 The cosmic censorship hypothesis
- 7 The Kerr metric: a gateway to the roots of gravity?
- 8 Galactic astronomy since 1950
- 9 Galaxy distribution functions
- 10 Nonlinear galaxy clustering
- 11 Quasars: progress and prospects
- 12 Decaying neutrinos in astronomy and cosmology
- 13 Cosmological principles
- 14 Anisotropic and inhomogeneous cosmologies
- 15 Mach's principle and isotropic singularities
- 16 Implications of superconductivity in cosmic string theory
- 17 The formation and evaporation of primordial black holes
- 18 Evaporation of two dimensional black holes
- 19 Topology and topology change in general relativity
- 20 Decoherence of the cluttered quantum vacuum
- 21 Quantum non-locality and complex reality
- 22 The different levels of connections between science and objective reality
8 - Galactic astronomy since 1950
Published online by Cambridge University Press: 15 December 2009
- Frontmatter
- Contents
- Author Addresses
- 1 Introduction
- 2 Exact and inexact solutions of the Einstein field equations
- 3 Inertial forces in general relativity
- 4 Relativistic radiation hydrodynamics: a covariant theory of flux-limiters
- 5 Relativistic gravitational collapse
- 6 The cosmic censorship hypothesis
- 7 The Kerr metric: a gateway to the roots of gravity?
- 8 Galactic astronomy since 1950
- 9 Galaxy distribution functions
- 10 Nonlinear galaxy clustering
- 11 Quasars: progress and prospects
- 12 Decaying neutrinos in astronomy and cosmology
- 13 Cosmological principles
- 14 Anisotropic and inhomogeneous cosmologies
- 15 Mach's principle and isotropic singularities
- 16 Implications of superconductivity in cosmic string theory
- 17 The formation and evaporation of primordial black holes
- 18 Evaporation of two dimensional black holes
- 19 Topology and topology change in general relativity
- 20 Decoherence of the cluttered quantum vacuum
- 21 Quantum non-locality and complex reality
- 22 The different levels of connections between science and objective reality
Summary
Galaxies are the building blocks of the Universe, and most of what we know about them has been discovered since Dennis Sciama became a research student. In the space available to me it is not possible to cover even in outline all significant developments during this period. So I have tried to concentrate on what seem to me to be the most important themes. My choice must surely be heavily influenced by personal taste and experience; I hope only that my prejudices are not too glaringly evident.
THE STRUCTURE OF THE MILKY WAY
Galactic astronomy in the 1950s was dominated by the discovery (Ewen & Purcell, 1951) of the 21 cm line predicted by H. C. van der Hulst in 1944. This made it possible for the first time to study the large-scale kinematics of the Milky Way. For the most part the 21 cm observations confirmed the picture of a disk in differential rotation developed by Oort more than twenty years before. However, there were surprises — most notably the discovery that the disk is warped rather than being perfectly flat (Burke, 1957; Kerr, 1957).
Extinction of stars by dust had first betrayed the existence of the interstellar medium (Trumpler 1930).
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- Chapter
- Information
- The Renaissance of General Relativity and CosmologyA Survey to Celebrate the 65th Birthday of Dennis Sciama, pp. 110 - 129Publisher: Cambridge University PressPrint publication year: 1993