Dynamically generated inflationary two-field potential via non-Riemannian volume forms
- We consider a simple model of modified gravity interacting with a single scalar field ϕ with weakly coupled exponential potential within the framework of non-Riemannian spacetime volume-form formalism. The specific form of the action is fixed by the requirement of invariance under global Weyl-scale symmetry. Upon passing to the physical Einstein frame we show how the non-Riemannian volume elements create a second canonical scalar field u and dynamically generate a non-trivial two-scalar-field potential Ueff(u,ϕ) with two remarkable features: (i) it possesses a large flat region for large u describing a slow-roll inflation; (ii) it has a stable low-lying minimum w.r.t. (u,ϕ) representing the dark energy density in the “late universe”. We study the corresponding two-field slow-roll inflation and show that the pertinent slow-roll inflationary curve ϕ = ϕ(u) in the two-field space (u,ϕ) has a very small curvature, i.e., ϕ changes very little during the inflationary evolution of u on the flat region of Ueff(u,ϕ). Explicit expressions are found for the slow-roll parameters which differ from those in the single-field inflationary counterpart. Numerical solutions for the scalar spectral index and the tensor-to-scalar ratio are derived agreeing with the observational data.
Author: | David BenistyORCiD, Eduardo I. Guendelman, Emil Nissimov, Svetlana Pacheva |
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URN: | urn:nbn:de:hebis:30:3-536050 |
DOI: | https://doi.org/10.1016/j.nuclphysb.2019.114907 |
ISSN: | 1873-1562 |
ISSN: | 0550-3213 |
Parent Title (German): | Nuclear Physics B |
Publisher: | Elsevier |
Place of publication: | Amsterdam |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2019/12/28 |
Date of first Publication: | 2019/12/28 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2020/05/07 |
Volume: | 951.2020 |
Issue: | 114907 |
Page Number: | 12 |
HeBIS-PPN: | 466011156 |
Institutes: | Physik / Physik |
Wissenschaftliche Zentren und koordinierte Programme / Frankfurt Institute for Advanced Studies (FIAS) | |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Sammlungen: | Universitätspublikationen |
Licence (German): | ![]() |