Positive running of the spectral index is achievable in Einstein-Gauss-Bonnet gravity with viable inflation, unlike standard scalar field and F(R) models which face challenges.
Fibre Inflation Meets Quintessence: Implications of Perturbative Stabilisation
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
In this paper, we have discovered a new avenue of fibre inflation in perturbative large volume scenario (pLVS) due to the redefinition of the base modulus. pLVS offers a novel regime where large volume of the internal space is guaranteed without the need of non-perturbative effects. In this setup, we study the possibility where a base redefinition allows to assess different versions of fibre inflation whose spectral index aligns with Atacama Cosmology Telescope (ACT) data and produces tensor-to-scalar ratio in the range $0.008\lesssim r\lesssim 0.01$ in different setups we have considered. The leading order flat direction - which in our case is the fibre modulus - is lifted with the combinations of string loop corrections, leading order $\alpha^{\prime 3}$$R^4$-correction, higher derivative $F^{4}$ corrections as well as our new ingredient redefinition of the modulus. Since recent Dark Energy Spectroscopic Instrument (DESI) results appear to favour a dynamical explanation for late-time acceleration over a simple cosmological constant, exploring quintessence offers a more suitable approach. In this lore, we also examine the quintessence sector to complete our model and account for both early- and late-time cosmic acceleration. In this framework, the poly-instanton correction generates a potential along the axionic directions, and we find that the resulting quintessence behaviour and the subsequent cosmological predictions about dark matter closely resemble the predictions of the original fibre inflation scenario studied earlier.
citation-role summary
citation-polarity summary
years
2026 4verdicts
UNVERDICTED 4roles
background 2polarities
background 2representative citing papers
Four Einstein-Gauss-Bonnet inflationary models are reconstructed from a chosen tensor-to-scalar ratio and shown to satisfy ACT and GW170817 constraints including scalar perturbation amplitude.
MCMC analysis of sixteen ghost-free f(R,G) inflation models shows all reproduce ns ≈ 0.97 at 60 e-folds with stable μ ≈ 0.1, preference set by Hubble parametrization.
Examines thermal effects on moduli in perturbatively stabilized LVS, deriving T_max dependence on loop corrections and showing thermal metastability is sensitive to post-inflationary history while favoring high-scale inflation.
citing papers explorer
-
Positive Running of the Spectral Index for Scalar Theory and Modified Gravity
Positive running of the spectral index is achievable in Einstein-Gauss-Bonnet gravity with viable inflation, unlike standard scalar field and F(R) models which face challenges.
-
Reconstructing ACT-compatible and GW170817-compatible Einstein-Gauss-Bonnet Inflation from the Observational Indices
Four Einstein-Gauss-Bonnet inflationary models are reconstructed from a chosen tensor-to-scalar ratio and shown to satisfy ACT and GW170817 constraints including scalar perturbation amplitude.
-
String-inspired Gauss-Bonnet Gravity Inflation and ACT
MCMC analysis of sixteen ghost-free f(R,G) inflation models shows all reproduce ns ≈ 0.97 at 60 e-folds with stable μ ≈ 0.1, preference set by Hubble parametrization.
-
Thermal effects and finite-temperature cosmology in perturbatively stabilized large volume scenarios
Examines thermal effects on moduli in perturbatively stabilized LVS, deriving T_max dependence on loop corrections and showing thermal metastability is sensitive to post-inflationary history while favoring high-scale inflation.