晶格QCD中夸克-胶子耦合的高精度计算
近日，西班牙CSIC-瓦伦西亚大学Alberto Ramos团队报道了晶格QCD中夸克-胶子耦合的高精度计算。2026年4月8日，《自然》杂志发表了这一成果。
现代粒子物理实验（如欧洲核子研究中心大型强子对撞机上的质子-质子对撞）的结果，在很大程度上依赖于基于基本相互作用对散射过程的精确描述。在所有已知的贡献相互作用中，对强核力的有限理解是理论不精确的一个关键来源。在基本层面上，强力由量子色动力学（即夸克与胶子的理论）描述。其耦合常数αs在高能下变弱（渐近自由），使得αs的幂级数展开成为可能，但夸克被禁闭在强子束缚态中通常需要额外的模型假设。因此，从实验确定αs大多仍带有较大的系统理论误差。
研究组报告了基于低能实验输入，结合在时空格点上对量子色动力学第一性原理表述的大规模数值模拟，以空前的精度无模型地确定了αs。其不确定度约为所有其他结果总和的一半，主要源于蒙特卡洛统计评估，并具有清晰的概率解释。所得的αs值既能借助格点量子色动力学描述低能强子物理，也能利用微扰展开描述高能散射。通过消除一个理论不确定性来源，研究组对αs的估算能够显著改进对许多高能实验的分析。这将有助于提高发现未知物理微小效应的可能性，并能够对标准模型进行严格的精确检验。
附：英文原文
Title: High-precision calculation of the quark–gluon coupling from lattice QCD
Author: Dalla Brida, Mattia, Hllwieser, Roman, Knechtli, Francesco, Korzec, Tomasz, Ramos, Alberto, Sint, Stefan, Sommer, Rainer
Issue&Volume: 2026-04-08
Abstract: The outcomes of modern particle physics experiments, such as proton–proton collisions at the Large Hadron Collider at CERN (European Organization for Nuclear Research), depend crucially on the precise description of the scattering processes in terms of the fundamental forces. Among all the known forces that contribute, the limited understanding of the strong nuclear force is a key source of inaccuracy. At the fundamental level, the strong force is described by quantum chromodynamics, the theory of quarks and gluons. Their coupling, αs, becomes weaker at high energies (asymptotic freedom), enabling power series expansions in αs, but the confinement of quarks in hadronic bound states usually requires additional model assumptions. Consequently, determinations of αs from experiment mostly remain with large systematic theory errors1,2. Here we report the model-free determination of αs with unprecedented precision from low-energy experimental input combined with large-scale numerical simulations of the first-principles formulation of quantum chromodynamics on a space–time lattice. The uncertainty, about half that of all other results combined3, originates predominantly from the statistical Monte Carlo evaluation and has a clear probabilistic interpretation. The result for αs describes both low-energy hadronic physics with the help of lattice quantum chromodynamics and high-energy scattering using the perturbative expansion. By removing a source of theoretical uncertainty, our estimate of αs could enable markedly improved analyses of many high-energy experiments4. This will contribute to the likelihood that small effects of yet unknown physics are uncovered, as well as enable stringent precision tests of the Standard Model.
DOI: 10.1038/s41586-026-10339-4
Source: https://www.nature.com/articles/s41586-026-10339-4
期刊信息
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
投稿链接：http://www.nature.com/authors/submit_manuscript.html
