Skip to content

Interferometer constraints on the inflationary field content

Research output: Contribution to journalArticlepeer-review

With an energy scale that can be as high as 1014 GeV, inflation may provide a unique probe of high-energy physics. Both scalar and tensor fluctuations generated during this early accelerated expansion contain crucial information about the particle content of the primordial universe. The advent of ground- and space-based interferometers enables us to probe primordial physics at length-scales much smaller than those corresponding to current CMB constraints. One key prediction of single-field slow-roll inflation is a red-tilted gravitational wave spectrum, currently inaccessible at interferometer scales. Interferometers probe directly inflationary physics that deviates from the minimal scenario and in particular additional particle content with sizeable couplings to the inflaton field. We adopt here an effective description for such fields and focus on the case of extra spin-2 fields. We find that a time-dependent sound speed for the helicity-2 modes can generate primordial gravitational waves with a blue-tilted spectrum, potentially detectable at interferometer scales.
Original languageEnglish
Article number31
Number of pages19
JournalJournal of Cosmology and Astroparticle Physics
Issue number03
Publication statusPublished - 13 Mar 2020


  • Iacconi_AAM

    Rights statement: This Accepted Manuscript is available for reuse under a CC BY-NC-ND 3.0 licence after the 12 month embargo period provided that all the terms and conditions of the licence are adhered to.

    Accepted author manuscript (Post-print), 1.92 MB, PDF document

    Due to publisher’s copyright restrictions, this document is not freely available to download from this website until: 13/03/21

    Licence: CC BY-NC-ND

Relations Get citation (various referencing formats)

ID: 20698592