Derive the dissipation coefficient and perturbation-growth function self-consistently

Derive the warm-inflation dissipation coefficient and the perturbation-growth function self-consistently in the Einstein–Gauss–Bonnet model, rather than relying on numerical fits obtained within general relativity.

Background

The warm-inflation analysis uses phenomenological or fitted descriptions for the dissipative coefficient and for the function describing the growth of inflaton perturbations sourced by radiation fluctuations. In particular, the paper states that no closed-form analytical solution is known for the coupled inflaton–radiation perturbation system and adopts a fitted form for the growth function.

The conclusion identifies a self-consistent calculation as preferable because the existing dissipation coefficient and growth-function fits were derived within general relativity, whereas the model includes a nontrivial Gauss–Bonnet coupling. Establishing these quantities directly in the modified-gravity setting would test the reliability of the predicted scalar spectrum and viable parameter region.

References

No closed-form analytical solution for this coupled system is known, and the function $G(Q_{\rm wi})$ must be determined numerically by solving the perturbation equations and fitting the result as a function of the dissipation ratio $Q_{\rm wi}$.

— Einstein-Gauss-Bonnet quintessential inflation: From super-inflation to emergent warm inflation  (2610.01665 - Chahboun et al., 1 Oct 2026) in Conclusion and comments, Section 6; Section 4, discussion following Eq. (59)