Large Gravitational Waves and Lyth Bound in Multi Brane Inflation
نویسنده
چکیده
It is shown that multi M5-brane inflation in heterotic M-theory gives rise to a detectable gravitational wave power spectrum with tensor fraction r typically larger than the projected experimental sensitivity, rexp = 0.01. A measurable gravitational wave power spectrum entails a large inflationary energy scale and a super-Planckian inflaton variation. They present serious problems for particle theory model building resp. a reliable effective field theory description. These problems are eased or even absent in multi-brane inflation models and multi M5-brane inflation, in particular. PACS: 98.80.Cq, 12.60.Jv, 11.25.Yb
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