Toward a gravitational network: Bridging metric-affine gravity and no-scale supergravity

TL;DR

This work investigates a bridge between metric-affine gravity and no-scale supergravity to enrich inflationary model-building. By matching Einstein-frame dynamics of representative metric-affine constructions (including Palatini-R^2, nonminimal couplings, pure gravitational actions, and Weyl-invariant variants) to the bosonic sector of no-scale supergravity, the authors identify corresponding superpotentials Z(T) that reproduce the same inflationary behavior. Although the correspondence is phenomenological rather than strictly formal, the study shows how noncanonical kinetic terms and scalar potentials found in metric-affine gravity can be realized within no-scale supergravity through carefully chosen superpotentials. Overall, the results broaden the set of viable no-scale inflationary models and demonstrate the versatility of the no-scale framework in accommodating inflationary dynamics compatible with observations.

Abstract

We consider a class of models in the framework of metric-affine gravity and establish their correspondence to the bosonic sector of a class of no-scale supergravity models. The excellent inflationary behavior of the gravitational models considered is carried over to the corresponding supergravity ones, thus, enriching the landscape of inflation-compatible models.

Figures (1)

• Figure 1: Visualization of the "bridge" linking no-scale supergravity with metric-affine gravity models. For simplicity, constants and numerical coefficients are omitted in the metric-affine models shown, though they are retained in the main text.