Behaviours of rip cosmological models in $f(Q,C)$ gravity

TL;DR

This paper explores rip cosmological models within $f(Q,C)$ gravity, analyzing their physical parameters, energy conditions, and compatibility with observational data, revealing models that avoid singularities and exhibit phantom behavior.

Contribution

It introduces a specific $f(Q,C)$ gravity model and analyzes its implications for rip cosmologies, including physical parameters and observational consistency.

Findings

Models exhibit phantom-like EoS parameters close to $\, ext{Lambda}$CDM.

Energy conditions show violation of strong energy constraint.

Models successfully avoid singularities and fit current cosmic data.

Abstract

In this study, the Universe's rip cosmology theories have been provided for the $f(Q,C)$ gravity theory, where $Q$ and $C$ stand for the non-metricity scalar and boundary term. We assumed $f(Q,C)=\alpha Q^{n}+\beta C$ and analyzed the nature of the physical parameters for the Little Rip, Big Rip and Pseudo Rip models. In the LR and PR models, the EoS parameter exhibits phantom characteristics but remains closely aligned with the $\Lambda$CDM line. After investigating the energy conditions, we recognised that our model violates the strong energy constraint. Avoiding singularity situations has been noted in all of these accelerated models. The characteristics of the jerk and snap parameters have been investigated. Our model provides an effective description of the Universe's evolutionary history and fits well with contemporary cosmic data.