Constraining viscous-fluid models in f(Q) gravity with data
Abstract We investigate the impact of bulk viscosity on the accelerating expansion and large-scale structure formation of a Universe in which the underlying gravitational interaction is described by f(Q) gravity. Various paradigmatic choices of the f(Q) gravity theory, including power-law, exponenti...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
SpringerOpen
2025-07-01
|
| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | https://doi.org/10.1140/epjc/s10052-025-14432-2 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Abstract We investigate the impact of bulk viscosity on the accelerating expansion and large-scale structure formation of a Universe in which the underlying gravitational interaction is described by f(Q) gravity. Various paradigmatic choices of the f(Q) gravity theory, including power-law, exponential, and logarithmic models, are considered. To test the cosmological viability of these f(Q) gravity models, we use the Baryon Acoustic Oscillations (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI) Survey, cosmic chronometers (CC) from Hubble measurements, the SNIa distance moduli measurements from the PantheonP + SH0ES, growth rate (f-data), and redshift-space distortions $$(f\sigma _8)$$ ( f σ 8 ) datasets, the latter two once the linear cosmological perturbations, growth rate f(z), and redshift-space distortion $$f\sigma _8(z)$$ f σ 8 ( z ) are studied. Thus, we perform the combined analyses for: PantheonP + SH0ES, PantheonP + SH0ES + f, and PantheonP + SH0ES + $$f\sigma _8$$ f σ 8 . We compute the best-fit values $$\varOmega _m,$$ Ω m , $$H_0\,\mathrm {(km/s/Mpc)},$$ H 0 ( km / s / Mpc ) , $$r_d,$$ r d , $$M_{abs},$$ M abs , $$\gamma ,$$ γ , $$\sigma _8,$$ σ 8 , n, p and $$\varGamma $$ Γ including the bulk viscosity coefficient $$\zeta .$$ ζ . Through a detailed statistical analysis, based on the Akaike Information Criterion (AIC) and Bayesian/Schwartz Information Criterion (BIC), a statistical comparison of the f(Q) gravity models with $$\varLambda $$ Λ CDM is made. Among the three f(Q) models, only the non-viscous f(Q) power-law model yields robust parameter estimates and substantial observational support without any outright rejections. In contrast, both exponential and logarithmic f(Q) models (with or without bulk viscosity) are rejected by multiple model selection criteria. Moreover, adding bulk viscosity consistently increases $$\varDelta $$ Δ AIC and $$\varDelta $$ Δ BIC values, indicating that its inclusion is not statistically justified. |
|---|---|
| ISSN: | 1434-6052 |