New Tools to Study Strong Interaction Physics

公认的强核力理论，将原子核保持在一起，称为QCD（量子色动力学）已经知道了35年，但非常难以使用，并且在它最突出的地区知之甚少;例如，我们知道质子和中子（统称为“核子”）是由更小的成分夸克和胶子组成的，但它们如何组装成核子的确切情况充其量仍然是模糊的。 在这项资助中，Belitsky和Lebed将使用各种高性能的数学工具，通常是从弦理论中借用的工具，在这个复杂的领域取得进展。贝利茨基是广义部分子分布理论的专家，广义部分子分布是核子中最精确定义的可观测量，而列别德是大Nc QCD的专家，在大Nc QCD中，通过增加比自然界中更多的自由度，解决QCD变得更简单。 此外，Belitsky还精通一种称为可积性的强大技术，其中QCD和类似理论可以在数学上与铁磁体和其他“自旋链”等系统的物理学相关。 与此同时，Lebed正在研究“全息QCD”，这是基于弦理论的一个想法，即QCD和相关的强相互作用理论可以与弯曲空间上的弱相互作用引力相关。 贝利茨基和列别德将分别指导一位博士。学生在这些项目中。

The accepted theory of the strong nuclear force that holds atomic nuclei together, called QCD (Quantum Chromodynamics) has been known for 35 years, but is extraordinarily difficult to use and is poorly understood in precisely the regions where it is most prominent; for example, we know that protons and neutrons (collectively, "nucleons") are made of smaller constituents named quarks and gluons, but exactly how they are assembled into nucleons remains murky at best. In this grant, Belitsky and Lebed will use a variety of high-powered mathematical tools, often ones borrowed from string theory, to make headway in this complicated landscape. Belitsky is an expert in the theory of generalized parton distributions, which are the most precisely defined observables possible for nucleons, while Lebed is an expert on large Nc QCD, in which solving QCD becomes paradoxically simpler to solve by adding more degrees of freedom than occur in nature. In addition, Belitsky has become adept in a powerful technique called integrability, in which QCD and similar theories can be mathematically related to the physics of systems like ferromagnets and other "spin-chains". Meanwhile, Lebed is studying "holographic QCD," which is based upon an idea from string theory, that QCD and related strongly-interacting theories can be related to weakly-interacting gravity on a curved space. Each of Belitsky and Lebed will mentor a Ph.D. student in these project areas.