Generalised conditions for rapid-turn inflation

Journal of Cosmology and Astroparticle Physics, vol. 2024, pp. 079

Abstract

Abstract Rapid-turn slow-roll inflationary trajectories have been shown to be an attractor in two-field models, provided the turn rate is near constant and larger than the slow-roll parameters. These trajectories can produce primordial spectra consistent with current observations on CMB scales. We present the generalized consistency condition for sustained rapid-turn inflationary trajectory with two fields, arbitrary field-space metric and potential valid for any value of the turn rate. This has to be supplemented by a second condition to ensure slow roll evolution. Both conditions together constitute a tool to identify inflationary trajectories with arbitrary values of the turning rate without having to solve the equations of motion. We present a Python package for the numerical identification of regions in field-space and parameter space that allow for rapid-turn trajectories.

Authors 3

1. Raúl Wolters Aachen Institute Lorentz of Theoretical Physics

   Leiden University · Utrecht University

   Affiliation as printed

   Institute Lorentz of Theoretical Physics, Leiden University, Leiden 2333 CA, The Netherlands

   Institute for Theoretical Physics, Utrecht University, Utrecht 3584 CE, The Netherlands

2. Oksana Iarygina

   Stockholm University · KTH Royal Institute of Technology

   Affiliation as printed

   Nordita, KTH Royal Institute of Technology and Stockholm University, Hannes Alfvéns väg 12, Stockholm 10691, Sweden

   The Oskar Klein Centre, Department of Astronomy, Stockholm University, Stockholm 10691, Sweden

3. Ana Achúcarro Aachen Institute Lorentz of Theoretical Physics

   Leiden University · University of the Basque Country

   Affiliation as printed

   Department of Theoretical Physics, University of the Basque Country, UPV-EHU, Bilbao 48080, Spain

   Institute Lorentz of Theoretical Physics, Leiden University, Leiden 2333 CA, The Netherlands