发表机构
School of Physics and Astronomy, University of Birmingham; Department of Physics, University of Trento; Trento Institute for Fundamental Physics and Applications (TIFPA)-INFN（伯明翰大学物理与天文学院; 特伦托大学物理系; 特伦托基础物理与应用研究所（TIFPA）-意大利国家核物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文利用高斯过程非参数方法，结合超新星与BAO/CC数据确定空间曲率，结果轻微倾向开放宇宙，且不依赖CMB或参数化暗能量模型。
AI 中文摘要
我们提出了一种仅使用晚期几何探针的非参数空间曲率确定方法。在高斯过程平滑先验下，我们联合约束无量纲膨胀历史和$\Omega_K$，将三个Ia型超新星（SNeIa）样本与DESI DR2视线方向重子声学振荡（BAO）或宇宙学钟（CC）数据相结合。基于我们的基线SNeIa+BAO分析，对于PantheonPlus、DES Dovekie和Union3 SNeIa样本，我们分别得到$\Omega_K=0.219^{+0.110}_{-0.111}$、$\Omega_K=0.330^{+0.098}_{-0.150}$和$\Omega_K=0.260^{+0.124}_{-0.127}$。这些非参数结果轻微倾向于开放宇宙，支持了近期在此方向上的暗示，并将该方法先前应用的灵敏度提高了最多约2.5倍。我们发现将SNeIa与CC结合时得到一致的约束，而将SNeIa数据限制在BAO覆盖的红移范围内则会略微削弱约束，并将PantheonPlus的中心值移至$\Omega_K<0$。我们的结果仅依赖于晚期相对距离和膨胀速率，因此对绝对距离尺度校准不敏感，同时既不依赖宇宙微波背景数据，也不依赖参数化暗能量模型。
英文摘要
We present a nonparametric determination of spatial curvature using only late-time geometrical probes. Under a Gaussian Process smoothness prior, we jointly constrain the dimensionless expansion history and $Ω_K$, combining three Type Ia Supernovae (SNeIa) samples with either DESI DR2 line-of-sight baryon acoustic oscillations (BAO) or cosmic chronometers (CC) data. From our baseline SNeIa+BAO analyses we find $Ω_K=0.219^{+0.110}_{-0.111}$, $Ω_K=0.330^{+0.098}_{-0.150}$ and $Ω_K=0.260^{+0.124}_{-0.127}$ for the PantheonPlus, DES Dovekie and Union3 SNeIa samples respectively. These nonparametric results mildly favour an open Universe, supporting recent hints in this direction, and improve on the sensitivity of a previous application of the method by up to a factor of $\sim 2.5$. We find consistent constraints combining SNeIa and CC, whereas restricting SNeIa data to the redshift range covered by BAO somewhat weakens the constraints and shifts the PantheonPlus central value to $Ω_K<0$. Our results depend only on late-time relative distances and expansion rates, making them insensitive to the absolute distance scale calibration, while relying neither on Cosmic Microwave Background data nor on a parametric dark energy model.
Comments6 pages, 1 figure, to be submitted to MNRAS letters
