Circumventing the Ricci-inverse no-go theorem with complexifiable singularities: a novel dark energy model

TL;DR

This paper introduces a new class of Ricci-inverse gravity theories that avoid singularities and can explain the universe's accelerated expansion as a stable attractor, offering a viable dark energy model.

Contribution

It presents a novel method to bypass the Ricci-inverse no-go theorem, enabling Ricci-inverse cosmologies to model dark energy without singularities.

Findings

Successfully designed Ricci-inverse models with stable accelerated expansion

Circumvented the no-go theorem using complexifiable singularities

Demonstrated viability of Ricci-inverse theories as dark energy models

Abstract

Ricci-inverse gravity is a new type of fourth-order gravity theory based on the anti-curvature tensor, that is, the inverse of the Ricci tensor. In this context, we introduce a novel method to circumvent the binding effects of a well-known no-go theorem for cosmic trajectories that cannot smoothly join a decelerated cosmic age with the current accelerated expansion of the universe. We therefore design a new class of Ricci-inverse theories whose cosmologies, without falling into no-go singularities, achieve the observed expansion as a stable attractor solution. This new perspective retrains Ricci-inverse cosmologies as viable dark energy models.