广义Lipkin-Meshkov-Glick哈密顿量
Extended Lipkin-Meshkov-Glick Hamiltonian
摘要：
设计Lipkin-Meshkov-Glick（LMG）模型来检验不同近似形式对处理多粒子系统的有效性。该模型被构造为精确可解且非平凡的，以捕捉真实物理系统的一些主要特征。在目前的贡献，我们明确审查的事实，不同的多体近似通常用于在物理学的不同领域显然无法描述精确的LMG解决方案。与LMG模型所采用的假设类似，我们提出了一个新的基于一般两体相互作用的哈密顿量。新的模型（扩展LMG）不仅比原来的LMG模型更一般，因此，具有潜在的更大的适用范围，而且其精确解背后的物理可以更好地捕捉到常见的多体近似。在这种改进的基础上，是一个新的长期的哈密顿量，取决于数量的成分和极化的系统;相关的对称性破缺进行了讨论，以及一些影响更现实的系统的研究。
英文摘要：
The Lipkin-Meshkov-Glick (LMG) model was devised to test the validity of different approximate formalisms to treat many-particle systems. The model was constructed to be exactly solvable and yet non-trivial, in order to capture some of the main features of real physical systems. In the present contribution, we explicitly review the fact that different many-body approximations commonly used in different fields in physics clearly fail to describe the exact LMG solution. With similar assumptions as those adopted for the LMG model, we propose a new Hamiltonian based on a general two-body interaction. The new model (Extended LMG) is not only more general than the original LMG model and, therefore, with a potentially larger spectrum of applicability, but also the physics behind its exact solution can be much better captured by common many-body approximations. At the basis of this improvement lies a new term in the Hamiltonian that depends on the number of constituents and polarizes the system; the associated symmetry breaking is discussed, together with some implications for the study of more realistic systems.
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。
