Topological Solitons in Low-energy Effective Lagrangians

我们对以下两个课题进行了研究。qcd重子中的拓扑孤子可以看作介子系统中的拓扑孤子（Skyrmions）。简单的Skyrme模型能以30%的准确度解释核子的性质。第一个项目是通过将矢量介子纳入系统来提高数值一致性。修正后的模型是一个温伯格型手性模型，由于涉及到几个有待确定的新函数，该模型变得相当复杂。然而，我们获得的最佳拟合精度不超过25%。我们的下一个项目是研究温伯格型手性模型中包含的主要衰变为介子的准稳定孤子。我们预测这是最近发现的介子，因为它主要在介子中衰变。我们对一个准稳定孤子进行了数值研究，以确定它的质量和寿命。我们也尝试给准稳定孤子适当的量子数，但没有成功，因为拓扑孤子的同位旋和自旋不能独立地分配给skyrmions。弦理论中的拓扑孤子人们认为，基本粒子的终极理论是弦理论。如果所有的基本粒子都能从26维玻色子弦中推导出来，那将是令人兴奋的。作为实现这一目标的第一个项目，我们已经证明了10维超弦是从26维玻色子弦中产生的，其中时空旋量是拓扑孤子。在我们的工作中，我们明确地构造了一个OSp(9,1/2)xOSp（3,3/6）超多元作为26维玻色子弦的拓扑孤子。这里，OSp（9,1/2）超多元精确地描述了10维超弦。我们还证明了OSp（3,3/6）超多元是一致解耦的，其机制类似于协变弦理论中的不去定理。

We have made researches on the following two subjects.1. Topological Solitons in QCDBaryons can be considered as topological solitons (Skyrmions) in the system of mesons. The simple Skyrme model accounts for properties of nucleons with 30 % of accuracy. The first project was to improve numerical agreement by including vector mesons into the system. The modified model, which is a Weinberg-type chiral model, has become considerably complicated since it involves several new functions to bedetermined. However, the best fit we obtained was not better than 25% of accuracy. Our next project was to study quasi-stable solitons, which the Weinberg-type chiral model contains, decaying mainly into -mesons. We predict this to be the -meson recently discovered because it decays mainly in -mesons. We made numerical studies of a quasi-stable soliton to determine its mass and life-time. We have also tried to give proper quantum numbers to the quasi-stable solitons, without success, because isospin and spin of the topological soliton cannot be assigned independently to the Skyrmions.2. Topological Solitons in String TheoriesIt is believed that the ultimate theory of the elementary particles is the string theory. It would be exciting if all the elementary particles can be derived from the 26-dimensional bosonic sring. As a first project towards this goal we have shown that the 10-dimensional superstring emerges from the 26-dimensional bosonic string, where the space-time spinors are topological solitons. In our work we have explicitly constructed an OSp(9,1/2)xOSp(3,3/6) supermultiplet as topological solitons in the 26-dimensional bosonic string. Here, the OSp(9,1/2) supermultiplet describes precisely the 10-dimensional superstring. We have also proved that the OSp(3,3/6) supermultiplet is decoupled consistently by a mechanism similar to the no-go theorem in the covariant string theory.