论文标题
贝叶斯的速度快:通过减少基础方法模拟的协变能量密度的不确定性定量
Bayes goes fast: Uncertainty Quantification for a Covariant Energy Density Functional emulated by the Reduced Basis Method
论文作者
论文摘要
通过实验性结合能和几种魔术和半魔法核的电荷半径告知,使用原则的贝叶斯统计框架对协变量密度的功能进行校准。通过实施减少基础方法(RBM),通过仿真高保真模型来实现校准所需的贝叶斯采样,这是一组降低降低性降低技术,这些技术可以加快涉及涉及部分微分方程的计算的速度,从而涉及多个数量级。我们构建的RBM模拟器 - 仅使用100个高保真模型评估 - 能够在个人计算机上以数十毫秒的数十毫秒来准确地重现模型计算,与原始求解器相比,速度的增加了近3300倍。除了对参数的后验分布的分析外,我们还提出了预测,对未包含的观察结果进行了正确估计的不确定性,特别是中子皮肤厚度为208pb和48ca,如Prex和Crex协作所报道。 RBM的直接实施和出色的性能使其成为协助核理论社区提供可靠估计的理想工具,并通过适当量化的物理可观察到的不确定性。考虑到最近就职典礼和未来的实验和观察设施的数据的预期丰富性,这种不确定性量化工具将成为必不可少的。
A covariant energy density functional is calibrated using a principled Bayesian statistical framework informed by experimental binding energies and charge radii of several magic and semi-magic nuclei. The Bayesian sampling required for the calibration is enabled by the emulation of the high-fidelity model through the implementation of a reduced basis method (RBM) - a set of dimensionality reduction techniques that can speed up demanding calculations involving partial differential equations by several orders of magnitude. The RBM emulator we build - using only 100 evaluations of the high-fidelity model - is able to accurately reproduce the model calculations in tens of milliseconds on a personal computer, an increase in speed of nearly a factor of 3,300 when compared to the original solver. Besides the analysis of the posterior distribution of parameters, we present predictions with properly estimated uncertainties for observables not included in the fit, specifically the neutron skin thickness of 208Pb and 48Ca, as reported by PREX and CREX collaborations. The straightforward implementation and outstanding performance of the RBM makes it an ideal tool for assisting the nuclear theory community in providing reliable estimates with properly quantified uncertainties of physical observables. Such uncertainty quantification tools will become essential given the expected abundance of data from the recently inaugurated and future experimental and observational facilities.