Space-times with constant vacuum energy density and a conformal Killing vector
We find a class of solutions to the Einstein field equations with constant vacuum energy density (''cosmological constant'') that has a similarity symmetry of the second kind. We show this symmetry to be a global conformal symmetry. Nontrivial analytic solutions are given and one in particular (exhibiting intrinsic symmetry) is shown to evolve to a nonempty Robertson-Walker space-time with ''steady-state'' metric. This is found to be due to particle production associated with the negative matter pressure that is required by the assumed symmetry. These models can describe, classically, an origin of the Universe in terms of particle production from the vacuum, driving an exponential (de Sitter) expansion. This solution is inhomogeneous and anisotropic, but tends to homogeneity and isotropy at early times and large distances, and at late times and small distances. The solution therefore corresponds to the outward motion of a spherical disturbance which distorts the local homogeneity and isotropy in an asymptotically homogeneous and isotropic universe. The limiting homogeneous and isotropic forms are discussed.
- Research Organization:
- Astronomy Group, Department of Physics, Queen's University at Kingston, Kingston, Ontario K7L 3N6 Canada
- OSTI ID:
- 6268258
- Journal Information:
- Phys. Rev. D; (United States), Vol. 27:6
- Country of Publication:
- United States
- Language:
- English
Similar Records
Light-cone averages in a Swiss-cheese universe
Short distance and initial state effects in inflation: Stress tensor and decoherence
Related Subjects
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
EINSTEIN FIELD EQUATIONS
VACUUM STATES
COSMOLOGICAL MODELS
ENERGY DENSITY
METRICS
PARTICLE PRODUCTION
SPACE-TIME
SYMMETRY BREAKING
UNIVERSE
EQUATIONS
FIELD EQUATIONS
MATHEMATICAL MODELS
640106* - Astrophysics & Cosmology- Cosmology
645400 - High Energy Physics- Field Theory