Aligned natural inflation in the Large Volume Scenario

Stephen Angus, Kang Sin Choi, Chang Sub Shin

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


We embed natural inflation in an explict string theory model and derive observables in cosmology. We achieve this by compactifying the type IIB string on a Calabi-Yau orientifold, stabilizing moduli via the Large Volume Scenario, and configuring axions using D7-brane stacks. In order to obtain a large effective decay constant, we employ the Kim-Nilles-Peloso alignment mechanism, with the required multiple axions arising naturally from generically anisotropic bulk geometries. The bulk volumes, and hence the axion decay constants, are stabilized by generalized one-loop corrections and subject to various conditions: the Kähler cone condition on the string geometry; the convex hull condition of the weak gravity conjecture; and the constraint from the power spectrum of scalar perturbations. We find that all constraints can be satisfied in a geometry with relatively small volume and thus heavy bulk axion mass. We also covariantize the convex hull condition for the axion-dilaton-instanton system and verify the normalization of the extremal bound.

Original languageEnglish
Article number248
JournalJournal of High Energy Physics
Issue number10
StatePublished - Oct 2021

Bibliographical note

Publisher Copyright:
© 2021, The Author(s).


  • Cosmology of Theories beyond the SM
  • Flux compactifications


Dive into the research topics of 'Aligned natural inflation in the Large Volume Scenario'. Together they form a unique fingerprint.

Cite this