The Cosmological Constant Problems
@inproceedings{Weinberg2000TheCC, title={The Cosmological Constant Problems}, author={Steven Weinberg}, year={2000} }
The old cosmological constant problem is to understand why the vacuum energy is so small; the new problem is to understand why it is comparable to the present mass density. Several approaches to these problems are reviewed. Quintessence does not help with either; anthropic considerations offer a possibility of solving both. In theories with a scalar field that takes random initial values, the anthropic principle may apply to the cosmological constant, but probably to nothing else.
209 Citations
Anthropic Approach to the Cosmological Constant Problems
- Physics
- 2003
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- Physics, Philosophy
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BRANE UNIVERSES AND THE COSMOLOGICAL CONSTANT
- Physics, Philosophy
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The cosmological constant problem and brane universes are reviewed briefly. We discuss how the cosmological constant problem manifests itself in various scenarios for brane universes. We review…
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An artificial scale of observable cosmological constant is dynamically related to its natural bare value due to an installation of relevant coherent state for the inflationary field in a finite…
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