A look at the abandoned contributions to cosmology of Dirac, Sciama, and Dicke
Abstract
The separate contributions to cosmology of the above researchers are revisited and a cosmology encompassing their basic ideas is proposed. We study Dirac's article on the large number hypothesis (1938), Sciama's proposal of realizing Mach's principle (1953), and Dicke's considerations (1957) on a flat-space representation of general relativity with a variable speed of light (VSL). Dicke's tentative theory can be formulated in a way which is compatible with Sciama's hypothesis on the gravitational constant G. Additionally, such a cosmological model is shown to satisfy Dirac's second `large number' hypothesis on the total number of particles in the universe being proportional to the square of the epoch. In the same context, Dirac's first hypothesis on an epoch-dependent G-contrary to his prediction- does not necessarily produce a visible time dependence of G. While Dicke's proposalreproduces the classical tests of GR in first approximation, the cosmological redshift is described by a shortening of measuring rods rather than an expansion of space. Since the temporal evolution of the horizon R is governed by \dot R(t) =c(t), the flatness and horizon problems do not arise in the common form.
- Publication:
-
Annalen der Physik
- Pub Date:
- February 2009
- DOI:
- 10.1002/andp.200810335
- arXiv:
- arXiv:0708.3518
- Bibcode:
- 2009AnP...521...57U
- Keywords:
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- Physics - General Physics;
- General Relativity and Quantum Cosmology
- E-Print:
- 15 pages LaTeX, v5: version (almost identical) accepted for publication in Annalen der Physik