Understanding helicity structure and the out-of-equilibrium dynamics of anomalies in high-energy QCD

虽然众所周知，宇宙中可见物质的最基本组成部分是质子和中子，它们本身由更基本的夸克和胶子组成，但这些物质的基本组成部分的性质和对称性的出现还远远没有被理解。基本对称性在上个世纪主导了物理学的概念进展，最终成功地用规范理论的语言提出了物理学的标准模型。对对称性和对称性破坏的考虑已经允许导出基本的自然规律和动力学，通过一组基本的“规则”和方程来表达和理解。然而，从上述方程中无法看出对称性破缺的有趣来源：量子反常与量子理论本身的（真空）结构有关，它们产生于自然界从经典到量子水平的过渡。反常的意义是巨大的，因为它们被认为是宇宙中物质-反物质不对称的原因。尽管它们对自然界有着深刻的重要性，量子反常现象的实验验证仍然是难以捉摸的，中性π介子的衰变或η素介子的质量是有限的例外。直到最近，才有可能对异常的非平衡动态进行经验验证：量子反常的一个引人注目的实验表现是拓扑跃迁的相互作用，例如通过手征磁效应（CME）在高能重离子碰撞中的sphalerons和大磁场。物质基本成分的许多其他性质是难以捉摸的，一个关键的例子是质子自旋的起源，其中只有大约30%可以通过实验追踪到它的成分，夸克和胶子。这个问题和其他问题是未来电子-离子-对撞机的中心目标。利用新的理论思想，我的目标是有助于理解高能QCD的自旋结构。对反常和拓扑动力学的实时动力学以及高能QCD结构的理论理解是极具挑战性的。因此，在这个建议中，我将概述如何使用新技术（如费米子和规范场的实时晶格模拟）和弦理论启发的方法（如世界线方法）来研究异常的非平衡动力学以及高能QCD的结构。

While it is well know that the most fundamental constituents of the visible matter in the universe are protons and neutron which themselves are comprised of the more fundamental quarks and gluons, the emergence of the properties and symmetries ofthese building blocks of matter is far from being understood.Elementary symmetries have dominated the conceptual progress in physics over the last century, culminating in the successful formulation of the standard model of physics, postulated in the language of gauge theories. Considerations about symmetry and symmetry violation have allowed to derive the basic laws and dynamics of nature, expressed and understood by an elementary set of 'rules' and equations. However an intriguing source of symmetry breaking cannot be perceived from the aforementioned equations: quantum anomalies are tied to the (vacuum) structure of the quantum theory itself and they arise from the passage between the classical to the quantum level of nature.The significance of anomalies out-of-equilibrium is enormous, as they are conjectured to be responsible for the observed matter-antimatter asymmetry of the universe.Despite their deep importance for nature, the experimental verification of quantum anomalies has remained elusive, with the decay of the the neutral pion or the mass of the eta-prime meson being limited exceptions. Only very recently, the empirical verification of the out-of-equilibrium dynamics of anomalies has become possible: a striking experimental manifestation of quantum anomalies out-of-equilibrium is the interplay of topological transitions, such as sphalerons, and large magnetic fields in high-energy heavy ion collisions via the Chiral Magnetic Effect (CME).Many other properties of the fundamental constituents of matter are elusive, a key example being the origin of the protons spin, of which only roughly 30% can be experimentally traced to its constituents, quarks and gluons. This and otherquestions are the central goals of the future Electron-Ion-Collider. Using noveltheoretical ideas I aim to contribute to the understanding of the spin structureof high energy QCD. The theoretical understanding of the real-time dynamics of anomalous and topological dynamics, as well as of the structure of high energy QCD is extremely challenging. In this proposal I will therefore outline how the out-of-equilibrium dynamics of anomalies, as well as the structure of high energy QCD, can be investigated using novel techniques such as real-time lattice simulations of fermions and gauge fields and string-theory-inspired methods such as the world-line method.