Testing a varying-Λ model for dark energy within co-varying physical couplings framework

• DOI: 10.1093/mnras/stac2039
• Publication Date: 2022-07-24T02:38:40Z
• Authors: R R Cuzinatto; R P Gupta; R F L Holanda; J F Jesus; S H Pereira
• Keywords: Ansatz; Parametrization (atmospheric modeling); Cosmological constant

ABSTRACT The Co-varying Physical Couplings (CPC) framework is a modified gravity set up assuming Einstein Field Equations wherein the quantities {G, c, Λ} are promoted to space–time functions. Bianchi identity and requirement of stress-energy tensor conservation entangle possible variations couplings Λ}, which forced co-vary as dictated by General Constraint (GC). In this paper, we explore cosmological model G, Λ functions redshift respecting GC CPC framework. We assume linear parametrization in terms scale factor a. use ansatz $\dot{G}/G = \sigma \left(\dot{c}/c \right)$ with σ constant deduce functional forms c c(z) G G(z). show that varying-{G, fits SNe Ia data H(z) 3. parameters can be constrained describe dark energy at background level.