发表机构
Department of Physics, S.P. College, Sido Kanhu Murmu University（Sido Kanhu Murmu大学SP学院物理系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究在CLASS中实现旋量场精质暗能量模型，结合多类观测数据约束参数，发现其与常数w模型预测偏差小，拟合结果与ΛCDM等无显著差异，为常数w暗能量提供场论实现。
AI 中文摘要
我们通过在爱因斯坦-玻尔兹曼求解器CLASS中实现旋量场形式的精质暗能量模型，研究其线性扰动宇宙学。利用马尔可夫链蒙特卡罗分析，结合Pantheon⁺ Ia型超新星、宇宙计时器、DESI DR2重子声学振荡、红移空间畸变以及Planck 2018 CMB距离先验数据，对模型参数进行约束。对于全部联合数据集，我们得到暗能量状态方程参数w_de=-0.9710⁺⁰.⁰²⁰⁶₋₀.₀₂₀₆，当前物质密度参数Ω_m0=0.2939⁺⁰.⁰⁰⁴⁷₋₀.₀₀₄₇，哈勃常数H0=66.23⁺⁰.⁵⁵₋₀.₅₃ km s⁻¹ Mpc⁻¹；对应的扰动量为σ8=0.7537⁺⁰.⁰⁰⁷⁶₋₀.₀₀₇₅，S8=0.7459⁺⁰.⁰⁰⁶⁷₋₀.₀₀₆₅。我们发现旋量精质模型在物质功率谱、增长速率可观测量fσ8、增长指数以及CMB温度各向异性谱中，与唯象的常数w模型的预测结果高度吻合，偏差通常低于1%。与ΛCDM和wCDM模型的拟合结果在统计上无显著差异，不过贝叶斯信息准则更倾向于更简单的ΛCDM模型。我们的结果表明，当一致处理旋量场精质模型的扰动演化时，该场景仍与当前宇宙膨胀历史和结构增长观测相符，为背景和线性扰动层面的常数w暗能量提供了具有场论动机的实现方案。
英文摘要
We investigate the linear perturbation cosmology of a spinor-field realization of quintessence dark energy by implementing the model in the Einstein--Boltzmann solver \texttt{CLASS}. The model parameters are constrained using a Markov Chain Monte Carlo analysis with Pantheon$^{+}$ Type Ia supernovae, cosmic chronometers, DESI DR2 baryon acoustic oscillations, redshift-space distortions, and Planck 2018 CMB distance-prior data. For the full combined dataset, we obtain $w_{\rm de}=-0.9710^{+0.0206}_{-0.0206}$, $Ω_{m0}=0.2939^{+0.0047}_{-0.0047}$, and $H_0=66.23^{+0.55}_{-0.53},\mathrm{kms^{-1}Mpc^{-1}}$. The corresponding perturbation quantities are $σ_8=0.7537^{+0.0076}_{-0.0075}$ and $S_8=0.7459^{+0.0067}_{-0.0065}$. We find that the spinor-quintessence model closely reproduces the predictions of a phenomenological constant-$w$ model in the matter power spectrum, growth-rate observable $fσ_8$, growth index, and CMB temperature anisotropy spectrum, with deviations generally below the percent level. A comparison with $Λ$CDM and $w$CDM shows statistically indistinguishable fits, although the Bayesian information criterion favors the simpler $Λ$CDM model. Our results demonstrate that the spinor-field quintessence scenario remains consistent with current expansion-history and structure-growth observations when its perturbation evolution is treated consistently, providing a field-theoretically motivated realization of constant-$w$ dark energy at the background and linear perturbation levels.
Comments19 pages, 5 figures
