Dust matter cosmology in modified symmetric teleparallel f(Q, T) gravity
Physics of the Dark Universe, cilt.54, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 54
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.dark.2026.102497
- Dergi Adı: Physics of the Dark Universe
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, INSPEC
- Anahtar Kelimeler: Cosmography, Dark energy, f(Q, T) gravity, Hubble tension, Observational constraints
- İstanbul Üniversitesi Adresli: Evet
Özet
We investigate the nonlinear f (Q, T) gravity model, f(Q,T)=αQn+βT+γ, which represents a nontrivial coupling between geometry and matter in the context of a dust-dominated Universe. The model parameters (H 0, α, β, γ, n) are constrained using recent cosmological observations, including Hubble parameter measurements H (z), the Pantheon+SH0ES dataset, and DESI BAO data. The analysis shows that the Hubble constant exhibits dataset-dependent variations, reflecting the persisting Hubble tension, while α and γ are tightly constrained and β remains weakly determined. The nonlinear exponent n introduces an additional degree of freedom that enhances the model’s flexibility in reproducing observational trends. The cosmographic diagnostics, including the deceleration, jerk, snap, and lerk parameters, indicate a Universe transitioning from early deceleration to late-time acceleration, with present values closely aligned with ΛCDM predictions and far-future behavior approaching a de Sitter phase. These results demonstrate that the nonlinear f (Q, T) model provides a simple and viable framework to describe late-time cosmic acceleration, accommodate observational tensions, and reproduce ΛCDM-like dynamics with subtle deviations.