Oscillatory Freeze from Inertial Holographic Dark Energy

TL;DR

This paper introduces a generalized holographic dark energy model with higher derivatives of the Hubble parameter, leading to oscillatory late-time cosmic behavior and an asymptotically Minkowski universe, consistent with current observational data.

Contribution

It proposes a novel holographic dark energy model incorporating second derivatives of the Hubble parameter, revealing oscillatory and relaxation dynamics not previously explored.

Findings

The model predicts exponentially damped oscillations in the Hubble parameter.

The universe approaches a Minkowski state without future singularities.

The model fits late-time cosmic expansion data with reduced chi-squared ~0.52.

Abstract

We study a generalized holographic dark energy model in which the infrared cutoff depends on the Hubble parameter and its first two time derivatives. The inclusion of the $\ddot H$ term introduces a finite relaxation timescale for the horizon degrees of freedom, which can be interpreted as an effective entropic inertia of the holographic vacuum energy. The resulting background dynamics admit late--time solutions in which the cosmic expansion gradually halts. In the underdamped regime, the Hubble parameter undergoes exponentially damped oscillations and asymptotically approaches $H\to0$. The scale factor grows monotonically but by a finite amount, while curvature invariants decay exponentially, leading to an asymptotically Minkowski spacetime without future singularities. We confront the full nonlinear background evolution with cosmic chronometer measurements of the Hubble parameter and find good agreement with current late--time expansion data, with a reduced chi--squared $\chi^2/\nu\simeq0.52$. At observable redshifts, oscillatory features are strongly suppressed and remain consistent with existing constraints.