Multibrane inflation and dynamical flattening of the inflaton potential

Journal Article · Thu Dec 15 04:00:00 EST 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.126004· OSTI ID:20774558

Cline, James M; Stoica, Horace ^[1]

---

1. Physics Department, McGill University, 3600 University Street, Montreal, Quebec, H3A 2T8 (Canada)

We investigate the problem of fine-tuning of the potential in the KLMT warped flux compactification scenario for brane-antibrane inflation in Type IIB string theory. We argue for the importance of an additional parameter {psi}{sub 0} (approximated as zero by KLMT), namely, the position of the antibrane, relative to the equilibrium position of the brane in the absence of the antibrane. We show that for a range of values of a particular combination of the Kaehler modulus, warp factor, and {psi}{sub 0}, the inflaton potential can be sufficiently flat. We point out a novel mechanism for dynamically achieving flatness within this part of parameter space: the presence of multiple mobile branes can lead to a potential which initially has a metastable local minimum, but gradually becomes flat as some of the branes tunnel out. Eventually the local minimum disappears and the remaining branes slowly roll together, with assisted inflation further enhancing the effective flatness of the potential. With the addition of Kaehler and superpotential corrections, this mechanism can completely remove the fine-tuning problem of brane inflation, within large regions of parameter space. The model can be falsified if future cosmic microwave background observations confirm the hint of a large running spectral index.

• OSTI ID: 20774558
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 12 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COMPACTIFICATION
CORRECTIONS
INFLATIONARY UNIVERSE
MEMBRANES
POTENTIALS
QUANTUM FIELD THEORY
RELICT RADIATION
SPACE
STRING MODELS