The role of anisotropy in f(Q) gravity: insights from cosmological observations
Abstract
We investigate the cosmological dynamics of Bianchi-I spacetime in symmetric teleparallel f(Q) gravity through a dynamical system approach to analyse observational constraints. By reformulating the modified field equations into an autonomous system, we analyse two representative f(Q) models and constrain their parameters using Pantheon Plus, DES Y5, DESI DR2, and compressed CMB data. The observational analysis yields consistent constraints across all dataset combinations and tightly bounds the anisotropic contribution, indicating that deviations from isotropy remain small. Both models reproduce the standard matter-dominated evolution and the observed late-time accelerated expansion while exhibiting distinct dark-energy dynamics. Model I undergoes a smooth phantom-divide crossing and approaches a de Sitter phase in the asymptotic future, whereas Model II evolves from an early phantom regime toward a cosmological-constant-like state around the present epoch, closely mimicking the late-time evolution of the ΛCDM model. These results indicate that anisotropic f(Q) cosmology remains consistent with current background observations while admitting characteristic dark-energy evolution that may be testable with future cosmological surveys.
Related
- Dark Energy Constraints and Joint Cosmological Inference from Mutually Inconsistent Observations
- Cosmological constraints on single-field inflation models from ACT/SPT data and observations at sub-Mpc scales
- Constraints from big bang nucleosynthesis and cosmological observations on varying Higgs vacuum expectation value
- Testing dark matter models and modified gravity theories with spatially resolved HI observations
- Consistency between cosmological and standard siren observations in evolving dark energy
BibTeX
@misc{murtaza2026role,
title = {{The role of anisotropy in $f(Q)$ gravity: insights from cosmological observations}},
author = {Ghulam Murtaza and Nandan Roy and Avik De},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.04235},
eprint = {2609.04235},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.04235},
}
RIS
TY - UNPB
TI - The role of anisotropy in f(Q) gravity: insights from cosmological observations
AU - Ghulam Murtaza
AU - Nandan Roy
AU - Avik De
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.04235
UR - https://arxiv.org/abs/2609.04235
AB - We investigate the cosmological dynamics of Bianchi-I spacetime in symmetric teleparallel f(Q) gravity through a dynamical system approach to analyse observational constraints. By reformulating the modified field equations into an autonomous system, we analyse two representative f(Q) models and constrain their parameters using Pantheon Plus, DES Y5, DESI DR2, and compressed CMB data. The observational analysis yields consistent constraints across all dataset combinations and tightly bounds the anisotropic contribution, indicating that deviations from isotropy remain small. Both models reproduce the standard matter-dominated evolution and the observed late-time accelerated expansion while exhibiting distinct dark-energy dynamics. Model I undergoes a smooth phantom-divide crossing and approaches a de Sitter phase in the asymptotic future, whereas Model II evolves from an early phantom regime toward a cosmological-constant-like state around the present epoch, closely mimicking the late-time evolution of the ΛCDM model. These results indicate that anisotropic f(Q) cosmology remains consistent with current background observations while admitting characteristic dark-energy evolution that may be testable with future cosmological surveys.
ER -