AI 中文总结
该研究通过动力学系统方法分析对称远平行$f(Q)$引力中Bianchi-I时空的宇宙学动力学，利用多组观测数据约束模型参数，发现各向异性偏差小，两个模型可重现标准宇宙学演化且暗能量动力学有特征，未来巡天或可检验。
AI 中文摘要
我们通过动力学系统方法研究对称远平行$f(Q)$引力中Bianchi-I时空的宇宙学动力学，以分析观测约束。通过将修正的场方程重新表述为自治系统，我们分析了两个具有代表性的$f(Q)$模型，并使用Pantheon Plus、DES Y5、DESI DR2和压缩CMB数据对其参数进行约束。观测分析在所有数据集组合中得出一致的约束，并对各向异性贡献进行了严格限制，表明各向同性偏差仍很小。两个模型均重现了标准物质主导的演化和观测到的晚期加速膨胀，同时呈现出不同的暗能量动力学：模型I经历了平滑的幻影分界线穿越，并在渐近未来趋近于德西特相；模型II从早期幻影态演化至当前 epoch 附近的宇宙学常数类态，紧密模仿$\boldsymbol{\rm \u039A}$CDM模型的晚期演化。这些结果表明，各向异性$f(Q)$宇宙学与当前背景观测一致，同时允许特征性的暗能量演化，未来宇宙学巡天或可对其进行检验。
英文摘要
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 $Λ$CDM 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.
