Answers are grounded in this paper and cite their sources.
Within the FLRW framework, we reconstruct the late-time expansion history in f(R,Lₘ,T) gravity using a redshift-dependent parametrization of the deceleration parameter. Its free parameters are constrained using Cosmic Chronometers~(CC), DESI DR2 baryon acoustic oscillations and Pantheon+ Type Ia supernovae data. The reconstructed expansion history consistently indicates a transition from deceleration to acceleration at zₜ≈0.6, with the present-day deceleration parameter constrained to q₀=-0.52 for both the CC and CC+DESI DR2 combinations and q₀=-0.50 for the combined CC+DESI DR2+Pantheon+ dataset. The Statefinder diagnostic reveals a non-monotonic kinematic evolution, with the reconstructed trajectories successively passing through Chaplygin gas-like, ΛCDM-like and quintessence-like regimes before returning toward the Chaplygin gas-like region near the present epoch. The reconstructed cosmic age is t₀≈13.0--13.3~Gyr, while the present-day effective equation of state parameter is ω₀≈ -0.70, consistent with accelerated expansion. The NEC and DEC remain satisfied, whereas the SEC is violated at late times. Statistical comparison using the AIC and BIC shows that the proposed model describes the observational data with an accuracy comparable to ΛCDM, while the BIC generally favors the simpler ΛCDM model because of its lower complexity.
No takes yet. Share an insight, caveat, or question.
Singh et al. (2026) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: