Investigating Inflation in Type IIA

Journal Article · Fri Dec 14 00:00:00 EST 2007 · Journal of High Energy Physics (JHEP)

DOI:https://doi.org/10.1088/1126-6708/2007/12/095· OSTI ID:921008

Hertzberg, Mark P; Kachru, Shamit; Taylor, Washington; Tegmark, Max

We prove that inflation is forbidden in the most well understood class of semi-realistic type IIA string compactifications: Calabi-Yau compactifications with only standard NS-NS 3-form flux, R-R fluxes, D6-branes and O6-planes at large volume and small string coupling. With these ingredients, the first slow-roll parameter satisfies {epsilon} {ge} 27/13 whenever V > 0, ruling out both inflation (including brane/anti-brane inflation) and de Sitter vacua in this limit. Our proof is based on the dependence of the 4-dimensional potential on the volume and dilaton moduli in the presence of fluxes and branes. We also describe broader classes of IIA models which may include cosmologies with inflation and/or de Sitter vacua. The inclusion of extra ingredients, such as NS 5-branes and geometric or non-geometric NS-NS fluxes, evades the assumptions used in deriving the no-go theorem. We focus on NS 5-branes and outline how such ingredients may prove fruitful for cosmology, but we do not provide an explicit model. We contrast the results of our IIA analysis with the rather different situation in IIB.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 921008
• Report Number(s): SLAC-PUB-12999; arXiv:0711.2512
• Journal Information: Journal of High Energy Physics (JHEP), Journal Name: Journal of High Energy Physics (JHEP)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
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HIGH ENERGY PHYSICS
STANFORD LINEAR ACCELERATOR CENTER
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