Grand unification and cosmological matter density
Two problems involving the consequences of grand unification for cosmology are investigated. In the first, the author explores the reconciliation of solution of the strong CP problem with an invisible axion with the explanation of the baryon number of the universe from grand unification. Imposition of Peccei-Quinn symmetry renders the baryon asymmetry too small, if the dominant mechanism is decay of superheavy scalars. The author shows that grand unified theories with automatic axion invisibility can avoid this difficulty. He investigates the level of baryosynthesis for several such models and finds that SU(7) is the most attractive model considered. In the second problem, the author investigates an inflationary universe with a non-zero cosmological constant. Standard inflation assumes a vanishing cosmological constant and hence predicts a universe at precisely the critical density (Omega/sub 0/ = 1). This prediction is modified if a non-zero cosmological constant is allowed. The author finds the new limits on Omega/sub 0/, which can have consequences for the searches for dark matter.
- Research Organization:
- North Carolina Univ., Chapel Hill (USA)
- OSTI ID:
- 6020085
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COSMOLOGY
GRAND UNIFIED THEORY
AXIONS
BARYON NUMBER
CP INVARIANCE
DENSITY
EXPANSION
FUNDAMENTAL CONSTANTS
NUCLEOSYNTHESIS
STRONG INTERACTIONS
BASIC INTERACTIONS
BOSONS
ELEMENTARY PARTICLES
FIELD THEORIES
GOLDSTONE BOSONS
INTERACTIONS
INVARIANCE PRINCIPLES
MATHEMATICAL MODELS
PARTICLE MODELS
PHYSICAL PROPERTIES
POSTULATED PARTICLES
SYNTHESIS
UNIFIED GAUGE MODELS
UNIFIED-FIELD THEORIES
640106* - Astrophysics & Cosmology- Cosmology
645400 - High Energy Physics- Field Theory