论文标题
部分可观测时空混沌系统的无模型预测
Pantheon+ constraints on dark energy and modified gravity: An evidence of dynamical dark energy
论文作者
论文摘要
储层计算是预测湍流的有力工具，其简单的架构具有处理大型系统的计算效率。然而，其实现通常需要完整的状态向量测量和系统非线性知识。我们使用非线性投影函数将系统测量扩展到高维空间，然后将其输入到储层中以获得预测。我们展示了这种储层计算网络在时空混沌系统上的应用，该系统模拟了湍流的若干特征。我们表明，使用径向基函数作为非线性投影器，即使只有部分观测并且不知道控制方程，也能稳健地捕捉复杂的系统非线性。最后，我们表明，当测量稀疏、不完整且带有噪声，甚至控制方程变得不准确时，我们的网络仍然可以产生相当准确的预测，从而为实际湍流系统的无模型预测铺平了道路。
We use the latest Type Ia supernovae sample Pantheon+ to explore new physics on cosmic scales. Specifically, in light of this new sample, we constrain the interacting dark energy and Hu-Sawicki $f(R)$ gravity models and employ the model-independent Gaussian processes to investigate whether there is an evidence of dark energy evolution. We find that Pantheon+ alone just gives weak constraints. However, a data combination of Pantheon+ with cosmic microwave background, baryon acoustic oscillations and cosmic chronometers gives a strong constraint on the modified matter expansion rate $ε=0.048\pm0.026$, which indicates that the momentum may transfer from dark energy to dark matter in the dark sector of the universe at the $1.85\,σ$ confidence level. In the meantime, we obtain a very tight constraint on the deviation from general relativity $\log_{10} f_{R0}< -6.32$ at the $2\,σ$ confidence level. Interestingly, when combining Pantheon+ with cosmic chronometers and cosmic microwave background data, we find a quintessence-like dark energy signal beyond the $2\,σ$ confidence level in the redshift range $z\in[0.70,1.05]$. This implies the nature of dark energy may actually be dynamical.
