2018/06/30 by Evan McDonough, Stephon Alexander · 2 citations
Physics and Astronomy · #Axion #Black Holes and Theoretical Physics #Cosmic string #Cosmology and Gravitation Theories #Gravitation #Gravitational wave #Inflation (cosmology) #Monodromy #Observable #Quantum Chromodynamics and Particle Interactions #String (physics) #String theory #astro-ph.CO #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1088/1475-7516/2018/11/030
published as JCAP11(2018)030 · 12 pages. v2: matches published version
openalex created_date 2018/06/21 · openalex publication_date 2018/11/19 · arxiv created 2018/11/20 · arxiv updated 2018/11/21 · openalex updated_date 2026/08/05
We consider gravitational wave production during inflation in type IIB string theory, and the possibility of observable gravitational waves in small field inflation. We show that the gauge field excitations on a set of coincident D7 branes, itself critical for moduli stabilization and hence intrinsic to inflation in string theory, coupled with axion fields from bulk fluxes, can act as a spectator sector during inflation. This results in a large production of chiral gravitational waves, even for relatively small values of the axion-gauge field coupling. We extend this to include a monodromy for the axion, and demonstrate that in both cases an observable level of gravitational waves is produced in small field inflation in string theory, with a spectrum that is maximally chiral. Finally, we demonstrate the consistency with moduli stabilization and with arbitrary (large or small field) inflationary dynamics of the host model, considering as an explicit example Kahler Moduli Inflation.