TransportEqsCurvedFieldSpace.pdf (2.07 MB)
Numerical evaluation of inflationary 3-point functions on curved field space
We extend the public CppTransport code to calculate the statistical properties of fluctuations in multiple-field inflationary models with curved field space. Our implementation accounts for all physical effects at tree-level in the 'in-in' diagrammatic expansion. This includes particle production due to time-varying masses, but excludes scenarios where the curvature perturbation is generated by averaging over the decay of more than one particle. We test our implementation by comparing results in Cartesian and polar field-space coordinates, showing excellent numerical agreement and only minor degradation in compute time. We compare our results with the PyTransport 2.0 code, which uses the same computational approach but a different numerical implementation, finding good agreement. Finally, we use our tools to study a class of gelaton-like models which could produce an enhanced non-Gaussian signal on equilateral configurations of the Fourier bispectrum. We show this is difficult to achieve using hyperbolic field-space manifolds and simple inflationary potentials.
Funding
Precisions tests of the inflationary scenario; G0918; EUROPEAN UNION; 308082
History
Publication status
- Published
File Version
- Accepted version
Journal
Journal of Cosmology and Astroparticle PhysicsISSN
1475-7516Publisher
IOP PublishingExternal DOI
Issue
07Volume
2018Page range
031Department affiliated with
- Physics and Astronomy Publications
Research groups affiliated with
- Astronomy Centre Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2018-07-18First Open Access (FOA) Date
2019-07-16First Compliant Deposit (FCD) Date
2018-07-18Usage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC