arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1905.02416hep-th
收藏

区间上的Grassmannian和Flag西格玛模型:相结构和L-依赖

Grassmannian and Flag sigma models on interval: phase structure and L-dependence

D. Pavshinkin

摘要:

讨论了有限区间上的二维格拉斯曼$SU(N)/S(U(N-2)\times U(2))$和旗$SU(N)/S(U(N-2)\times U(1)\times U(1))$西格玛模型,构造了大N极限下间隙方程的解析解.我们表明,旗模型承认一个均匀的解决方案的'混合'狄利克雷-诺依曼(DN)边界条件,只有足够大的长度$L$和经历了相变的阶段部分破缺规范对称性($U(1)$)的对称阶段($U(1)\times U(1)$)大$L$。另一方面,格拉斯曼模型有一个分离相,其中有一个质量和一个无质量的非零凝聚体,完全打破了$U(2)$规范对称性。该相存在于从上方有界的$L$区域上,并且必须使用Robin边界条件。我们还研究了L-依赖的总能量和检测固有的线性增长限制字符串在所有阶段。

英文摘要:

We discuss the two-dimensional Grassmannian $SU(N)/S(U(N-2)\times U(2))$ and the flag $SU(N)/S(U(N-2)\times U(1)\times U(1))$ sigma models on a finite interval and construct analytical solutions of gap equations in the large N limit. We show that the flag model admits a homogeneous solution for `mixed' Dirichlet-Neumann (DN) boundary conditions only for sufficiently large length $L$ and undergoes a phase transition from the phase of partly broken gauge symmetry ($U(1)$) to the symmetric phase ($U(1)\times U(1)$) for large $L$. On the other hand, the Grassmannian model has a detached phase with one massive and one massless non-zero condensates that completely break $U(2)$ gauge symmetry. This phase lives on a region of $L$ bounded from above and has to use the Robin boundary conditions. We also examine the L-dependence of the total energy and detect the linear growth inherent to confining string in all phases.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑