Title: Diagonal deformations of thin center vortices and their stability in Yang-Mills theories Show Chinese title

Title: 薄中心涡旋的对角变形及其在杨-米尔斯理论中的稳定性

Abstract: The importance of center vortices for the understanding of the confining properties of SU(N) Yang-Mills theories is well established in the lattice. However, in the continuum, there is a problem concerning the relevance of center vortex backgrounds. They display the so called Savvidy-Nielsen-Olesen instability, associated with a gyromagnetic ratio $g^{(b)}_m=2$ for the off-diagonal gluons. In this work, we initially consider the usual definition of a {\it thin} center vortex and rewrite it in terms of a local color frame in SU(N) Yang-Mills theories. Then, we define a thick center vortex as a diagonal deformation of the thin object. Besides the usual thick background profile, this deformation also contains a frame defect coupled with gyromagnetic ratio $g^{(d)}_m=1$, originated from the charged sector. As a consequence, the analysis of stability is modified. In particular, we point out that the defect should stabilize a vortex configuration formed by a pair of straight components separated by an appropriate finite distance. Show Chinese abstract

Abstract: 中心涡旋在理解SU(N)杨-米尔斯理论的约束性质方面的重要性已在格点上得到确立。 然而，在连续体中，存在关于中心涡旋背景相关性的问题。 它们表现出所谓的萨维迪-尼尔森-奥利森不稳定性，与非对角胶子的回磁比$g^{(b)}_m=2$相关。 在这项工作中，我们首先考虑通常定义的{\it 薄的}中心涡旋，并将其用SU(N)杨-米尔斯理论中的局部颜色框架来重新表述。 然后，我们将厚中心涡旋定义为薄物体的对角变形。 除了通常的厚背景轮廓外，这种变形还包含一个与回磁比$g^{(d)}_m=1$耦合的框架缺陷，该缺陷来源于带电部分。 因此，稳定性分析被修改。 特别是，我们指出，缺陷应稳定由一对相隔适当有限距离的直线成分组成的涡旋配置。