The Lyth Bound and the end of inflation

摘要: We derive an extended version of the well-known Lyth Bound on total variation inflaton field, incorporating higher-order corrections in slow roll. connect field Δ to both spectral index scalar perturbations and amplitude tensor modes. then investigate implications this bound for 'small field' potentials, where rolls off a local maximum potential. The during inflation is generically order mPl, even potentials with suppressed tensor/scalar ratio. Much excursion arises last e-fold single models problem can only be avoided via fine-tuning or imposition symmetry. Finally, we discuss result inflationary model building string theory supergravity.