We investigate the thermodynamics and phase structure of 𝑆⁢𝑈⁡(3) Yang-Mills theory on 𝕋2×ℝ2 in Euclidean spacetime in an effective-model approach. The model incorporates two Polyakov loops along two compactified directions as dynamical variables, and is constructed to reproduce thermodynamics on 𝕋2×ℝ2 measured on the lattice. The model analysis indicates the existence of a novel first-order phase transition on 𝕋2×ℝ2 in the deconfined phase, which terminates at critical points that should belong to the two-dimensional 𝑍2 universality class. We argue that the interplay of the Polyakov loops induced by their cross-term in the Polyakov-loop potential is responsible for the manifestation of the first-order transition.

中文翻译：

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具有空间压缩的 SU（3） Yang-Mills 理论中的新型一阶相变和临界点


我们以有效的模型方法研究了 SU（3） Yang-Mills 理论在欧几里得时空中 T2×R2 的热力学和相结构。该模型将沿两个压缩方向的两个 Polyakov 环作为动力学变量，并构建以重现在晶格上测量的 T2×R2 的热力学。模型分析表明，在去约束期中，T2×R2 上存在一种新的一阶相变，该相变终止于应属于二维 Z2 普遍性类的关键点。我们认为，Polyakov 环在 Polyakov 环势中的交叉项诱导的相互作用是一阶跃迁表现的原因。