2014/05/31 by Liam McAllister, Eva Silverstein, Alexander Westphal +1 · 3 citations
Mathematics · Physics and Astronomy · #Axion #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Inflation (cosmology) #Inflaton #Mathematical physics #Mathematics #Moduli #Monodromy #Particle physics #Physics #Pure mathematics #Quantum mechanics #String theory #Theoretical physics #astro-ph.CO #hep-ph #hep-th
paper · pdf · doi:10.1007/jhep09(2014)123
published as JHEP 1409:123,2014 · 36 pages; v2: fixed typos, added references
arxiv created 2014/07/09 · openalex publication_date 2014/09/01 · arxiv updated 2014/09/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Flux couplings to string theory axions yield super-Planckian field ranges along which the axion potential energy grows. At the same time, other aspects of the physics remain essentially unchanged along these large displacements, respecting a discrete shift symmetry with a sub-Planckian period. After a general overview of this monodromy effect and its application to large-field inflation, we present new classes of specific models of monodromy inflation, with monomial potentials μ 4−p ϕ p . A key simplification in these models is that the inflaton potential energy plays a leading role in moduli stabilization during inflation. The resulting inflaton-dependent shifts in the moduli fields lead to an effective flattening of the inflaton potential, i.e. a reduction of the exponent from a fiducial value p 0 to p < p 0. We focus on examples arising in compactifications of type IIB string theory on products of tori or Riemann surfaces, where the inflaton descends from the NS-NS two-form potential B 2, with monodromy induced by a coupling to the R-R field strength F 1. In this setting we exhibit models with p = 2/3, 4/3, 2, and 3, corresponding to predictions for the tensor-to-scalar ratio of r ≈ 0.04, 0.09, 0.13, and 0.2, respectively. Using mirror symmetry, we also motivate a second class of examples with the role of the axions played by the real parts of complex structure moduli, with fluxes inducing monodromy.