2 research outputs found
Inflation in Realistic D-Brane Models
We find successful models of D-brane/anti-brane inflation within a string
context. We work within the GKP-KKLT class of type IIB string vacua for which
many moduli are stabilized through fluxes, as recently modified to include
`realistic' orbifold sectors containing standard-model type particles. We allow
all moduli to roll when searching for inflationary solutions and find that
inflation is not generic inasmuch as special choices must be made for the
parameters describing the vacuum. But given these choices inflation can occur
for a reasonably wide range of initial conditions for the brane and antibrane.
We find that D-terms associated with the orbifold blowing-up modes play an
important role in the inflationary dynamics. Since the models contain a
standard-model-like sector after inflation, they open up the possibility of
addressing reheating issues. We calculate predictions for the CMB temperature
fluctuations and find that these can be consistent with observations, but are
generically not deep within the scale-invariant regime and so can allow
appreciable values for as well as predicting a potentially
observable gravity-wave signal. It is also possible to generate some admixture
of isocurvature fluctuations.Comment: 39 pages, 21 figures; added references; identified parameters
combining successful inflation with strong warping, as needed for consistency
of the approximation
Theory and Phenomenology of Type I strings and M-theory
The physical motivations and the basic construction rules for Type I strings
and M-theory compactifications are reviewed in light of the recent
developments. The first part contains the basic theoretical ingredients needed
for building four-dimensional supersymmetric models, models with broken
supersymmetry and for computing low-energy actions and quantum corrections to
them. The second part contains some phenomenological applications to brane
world scenarios with low values of the string scale and large extra dimensions.Comment: 129 pages, 7 eps figures, LaTeX, version to appear in Class. Quantum
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