AI 中文总结
该研究提出弱不可约性作为相共存的谱判据，明确 sector 平衡与连接性的谱作用，揭示真实相共存是有限尺寸避碰共存的奇异极限，并在装饰双层 Ising 模型中开展相关研究。
AI 中文摘要
传统有限尺寸理论通过自由能竞争和界面隧穿描述一阶共存，但 sector 平衡与 sector 间连接性的独特谱作用通常未明确体现。我们证明伪相变和热力学相共存由两个谱坐标控制：sector 失衡定位平衡位置，而连接性决定该平衡是否仍为避碰。在平衡处，有限连接性在对称化双 sector 表示中产生具有相等谱权重的唯一主导态。对于具有正界面张力的短程系统，界面成本指数抑制连接性、闭合共存分裂并渐近恢复可约性。因此，真实相共存是有限尺寸避碰共存的奇异极限，而一维伪相变保持有限连接性。在装饰双层 Ising 模型中，独立估计的共存间隙……
英文摘要
Conventional finite-size theories describe first-order coexistence through free-energy competition and interfacial tunneling, but the distinct spectral roles of sector balance and inter-sector connectivity are not usually explicit. We show that pseudo-transitions and thermodynamic phase coexistence are governed by two spectral coordinates: sector imbalance locates balance, while connectivity determines whether that balance remains avoided. At balance, finite connectivity produces a unique dominant state with equal spectral weights in the symmetrized two-sector representation. For short-range systems with positive interface tension, interfacial costs suppress the connectivity exponentially, close the coexistence splitting, and asymptotically restore reducibility. Thus, genuine phase coexistence emerges as the singular limit of finite-size avoided coexistence, whereas one-dimensional pseudo-transitions retain finite connectivity. In a decorated bilayer Ising model, the coexistence gap at independently est
Comments13 pages, 3 figures
Journal refPhys. Lett. A, 598, 132234 (2026)
DOI：10.1016/j.physleta.2026.132234
