Multi-pole Dark Energy

TL;DR

This paper introduces a multi-pole dark energy model with multiple poles in the scalar field's kinetic term, leading to a flat potential after transformation and resulting in a stable late-time universe dominated by scalar field potential.

Contribution

It generalizes pole dark energy models to include multiple poles, analyzing their effects on scalar field dynamics and late-time cosmological evolution.

Findings

Poles restrict the scalar field's original values.

Transformed fields have flat potentials even if original potentials are steep.

The two-pole model exhibits explicit late-time evolution; multiple poles have stable attractors.

Abstract

While a scalar field with a pole in its kinetic term is often used to study the cosmological inflation, it can also play the role of dark energy, which is called the pole dark energy model. We propose a generalized model that the scalar field may have two or even multiple poles in the kinetic term and we call it the multi-pole dark energy. We find the poles can place some restrictions on the values of the original scalar field with non-canonical kinetic term. After transforming to the canonical form, we get a flat potential for the transformed new scalar field even if the original field has a steep one. It The late-time evolution of the universe is obtained explicitly for the two pole model, while dynamical analysis is performed for the multiple pole model. We find that it does have a stable attractor solution, which corresponds to the universe dominated by the potential of the scalar field.