collaborators

5 papers

astro-ph.CO2026

Late-time Background Constraints on Linear and Non-linear Interacting Dark Energy after DESI DR2

David Figueruelo, Marcel van der Westhuizen, Amare Abebe +1

In this study, we present observational constraints on a class of phenomenological interacting dark energy (IDE) models that admit analytical solutions for the Hubble parameter $H(…

gr-qc2025

III. Interacting Dark Energy: Summary of Models, Pathologies, and Constraints

Marcel van der Westhuizen, Amare Abebe, Eleonora Di Valentino

We present an overview of the main results from our two companion papers that are relevant for observational constraints on interacting dark energy (IDE) models. We provide analyti…

astro-ph.CO2025

Compartmentalization in the Dark Sector of the Universe after DESI DR2 BAO data

Marcel van der Westhuizen, David Figueruelo, Rethabile Thubisi +3

We consider a non-linear interaction between the dark matter and dark energy components of the universe. In particular, within the FLRW geometry, where dark matter is described by…

gr-qc2025

I. Linear Interacting Dark Energy: Analytical Solutions and Theoretical Pathologies

Marcel van der Westhuizen, Amare Abebe, Eleonora Di Valentino

Interacting dark energy (IDE) models, in which dark matter (DM) and dark energy (DE) exchange energy through a non-gravitational interaction, have long been proposed as candidates…

gr-qc2025

II. Non-Linear Interacting Dark Energy: Analytical Solutions and Theoretical Pathologies

Marcel van der Westhuizen, Amare Abebe, Eleonora Di Valentino

We investigate interacting dark energy (IDE) models with phenomenological, non-linear interaction kernels , specifically $Q_{1}=3Hδ\left(\frac{ρ_{\rm dm}ρ_{\rm de}}{ρ_{\rm d…