Inflation with Gauss-Bonnet Correction and Higgs Potential

We investigate the cosmological inflation for the Einstein-Hilbert action plus the Higgs potential function and the Gauss-Bonnet term coupled with the Higgs scalar field through a dilaton-like coupling. Then, using the Friedmann-Lemaître-Robertson-Walker metric and considering the appropriate slow-roll parameters, we derive the necessary equations of motion. In the proposed model, since the e-folding integral cannot be easily solved analytically, we first utilize a well-known Taylor expansion. Then, with a certain range of values derived for the model parameters, utilizing a mixture of several diagrams and numerical analysis methods, we obtain results for the tensor-to-scalar ratio and the scalar spectral index that are in good agreement the latest observational data, particularly from ACT DR6, w within the acceptable range of the e-folding values. Also, in the absence of the Gauss-Bonnet term, we find that the inflationary observables are roughly the same as the predictions of the chaotic inflation model.

💡 Research Summary

The paper presents a novel inflationary scenario in which the Standard Model Higgs field plays the role of the inflaton, while a Gauss‑Bonnet (GB) curvature invariant is coupled to the Higgs through a dilaton‑like exponential function. The starting point is the four‑dimensional action

S = ∫ d⁴x √−g