Backreaction issues in axion monodromy and Minkowski 4-forms

Abstract

Abstract We clarify the differences between the usual Kaloper-Sorbo description of axion monodromy and the effective axionic potential in terms of Minkowski 4-forms derived in string compactifications. The fact that the metric of the 3-form fields coming from string theory is field dependent (unlike in Kaloper-Sorbo) leads to the backreaction issues recently studied in axion monodromy models within string theory. We reanalyse these problems in terms of the 4-forms focusing on the case in which the non-periodic scalars backreact on the Kahler metric of the inflaton reducing the physical field range. In the closed string sector of Type II Calabi-Yau compactifications with fluxes the metric becomes field dependent precisely when Δϕ ∼ M p , independently of the choice of fluxes. We propose, however, some counter-examples to this universal behaviour by including open string fields.

Keywords

• Cosmology of Theories beyond the SM
• Flux compactifications
• Superstring Vacua