Einstein-Gauss-Bonnet quintessential inflation: From super-inflation to emergent warm inflation
Abstract
This work presents a unified inflationary and late-time cosmology, developed within Einstein-Gauss-Bonnet gravity coupled to three scalar fields, governed by a single potential and coupling function throughout cosmic history. Permitting the Gauss-Bonnet coupling to depend on the field content, rather than assigning it arbitrarily, produces a two-phase inflationary scenario: the higher-curvature term initially drives expansion and later becomes a subdominant. The initial super-inflationary stage ends dynamically when the geometrically induced stabilization of the waterfall field fails, at a field value determined by the combination (n−1)Q. Coherent oscillations of the waterfall condensate serve as the initial radiation source, replacing conventional reheating and establishing the thermal bath necessary for the subsequent warm phase. Utilizing a two-stage dissipation mechanism with Γϕ∝ T3, the scalar and tensor spectra are derived while retaining Gauss-Bonnet contributions, demonstrating that the growth of inflaton fluctuations is regulated by the shear viscosity of the bath, which is essential for model viability. A quartic potential, previously excluded in the cold scenario, becomes viable, with ns within the Planck 1σ band and r suppressed. Agreement with the spectral index is generic, while internal consistency confines the model to a narrow band in (n−1)Q. Finally, the release of the third scalar near matter-radiation equality transforms a very small mass scale into a very large coupling by a logic inverse to the seesaw mechanism. At late times, the inflaton persists as dark energy.
Related
- Circuit Complexity of Scalar and Tensor Perturbations in Luminal Einstein--Gauss--Bonnet Inflation
- Early inflation in Gauss–Bonnet gravity coupled with a scalar field in an inverse-square potential
- Alleviating cosmological strong coupling with torsion in regularized 4D Einstein-Gauss-Bonnet gravity
- An Exact Single-Rotating Near-Horizon Geometry in Einstein-Gauss-Bonnet Gravity
- Nonlinear scalarization and thermodynamics in Einstein-Phantom scalar-Gauss-Bonnet theory
BibTeX
@misc{chahboun2026einsteingaussbonnet,
title = {{Einstein-Gauss-Bonnet quintessential inflation: From super-inflation to emergent warm inflation}},
author = {Omar Chahboun and Rachid Ahl Laamara and El Hassan Saidi},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.01665},
eprint = {2610.01665},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.01665},
}
RIS
TY - UNPB
TI - Einstein-Gauss-Bonnet quintessential inflation: From super-inflation to emergent warm inflation
AU - Omar Chahboun
AU - Rachid Ahl Laamara
AU - El Hassan Saidi
PY - 2026
DA - 2026/10/10
PB - arXiv
DO - 10.48550/arxiv.2610.01665
UR - https://arxiv.org/abs/2610.01665
AB - This work presents a unified inflationary and late-time cosmology, developed within Einstein-Gauss-Bonnet gravity coupled to three scalar fields, governed by a single potential and coupling function throughout cosmic history. Permitting the Gauss-Bonnet coupling to depend on the field content, rather than assigning it arbitrarily, produces a two-phase inflationary scenario: the higher-curvature term initially drives expansion and later becomes a subdominant. The initial super-inflationary stage ends dynamically when the geometrically induced stabilization of the waterfall field fails, at a field value determined by the combination (n−1)Q. Coherent oscillations of the waterfall condensate serve as the initial radiation source, replacing conventional reheating and establishing the thermal bath necessary for the subsequent warm phase. Utilizing a two-stage dissipation mechanism with Γ_ϕ∝ T^3, the scalar and tensor spectra are derived while retaining Gauss-Bonnet contributions, demonstrating that the growth of inflaton fluctuations is regulated by the shear viscosity of the bath, which is essential for model viability. A quartic potential, previously excluded in the cold scenario, becomes viable, with n_s within the Planck 1σ band and r suppressed. Agreement with the spectral index is generic, while internal consistency confines the model to a narrow band in (n−1)Q. Finally, the release of the third scalar near matter-radiation equality transforms a very small mass scale into a very large coupling by a logic inverse to the seesaw mechanism. At late times, the inflaton persists as dark energy.
ER -