Precision Physics in Finite and Infinite Volume

有限和无限体积中的精密物理

• 批准号: EP/X021971/1
• 负责人: Nils Hermansson Truedsson
• 金额: $ 24.26万
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX021971%2F1
• 关键词: Precision; Physics; Finite; Infinite; Volume

The Standard Model (SM) of particle physics has had great success in its many predictions, but in certain cases there appears to betension with experimental measurements. These discrepancies could be hints of physics hitherto unknown, so it is of greatimportance to discover all flaws in the model. In this two-year project I will do timely and ambitious low-energy SM calculationsneeded for precision tests that in the future can guide in the search for a new model.This project is divided in two areas. The first focusses on flavour physics where quark interactions lead tocharge-parity violation, a phenomenon connected to the matter-antimatter asymmetry of the Universe. I willhere study kaon decays in a finite-volume spacetime, including electromagnetic corrections. The major focus point will be how toanalytically convert finite-volume lattice results for these kaon decays to physical predictions. A key intermediate step will be theunderstanding of pion-pion scattering including electromagnetic corrections, which on its own also is of interest for extraction ofscattering parameters from the lattice.The second focus area concerns the muon magnetic moment for which a possible discrepancy with experiments has beendiscovered. The main focus here will be on analytical calculations to reduce the error on the SM prediction. In one sub-project we willderive the leading structure-dependent finite-volume effects for the hadronic vacuum polarisation allowing for future improvedprecision tests from lattice QCD+QED of the quantity in question. In the other sub-project we will derive short-distance constraints onthe electroweak contribution to the muon magnetic moment with the help of the operator product expansion. These short-distanceconstraints will reduce the current uncertainty on the electroweak contribution.

粒子物理学的标准模型（SM）在它的许多预言中取得了巨大的成功，但在某些情况下，它似乎与实验测量相矛盾。这些差异可能是迄今为止未知的物理暗示，因此发现模型中的所有缺陷至关重要。在这个为期两年的项目中，我将做及时和雄心勃勃的低能量SM计算所需的精度测试，在未来可以指导在寻找一个新的模型。第一个重点是味物理学，夸克相互作用导致电荷宇称破坏，这是一种与宇宙的物质-反物质不对称性有关的现象。我将在这里研究有限体积时空中的k介子衰变，包括电磁修正。主要的焦点将是如何将这些k介子衰变的有限体积晶格结果解析地转换为物理预测。一个关键的中间步骤将是理解包括电磁修正在内的π-π散射，这本身也是从晶格中提取散射参数的兴趣所在。第二个焦点领域涉及μ子磁矩，其中发现了与实验可能存在的差异。这里的主要重点将是分析计算，以减少误差的SM预测。在一个子项目中，我们将推导出强子真空极化的主要结构相关有限体积效应，以便将来从格点QCD+QED中对所讨论的量进行更精确的测试。在另一个子项目中，我们将借助算符乘积展开导出关于μ子磁矩的电弱贡献的短距离约束。这些短距离的约束将减少电流对电弱贡献的不确定性。