标题： 经典和非相对论量子力学中出现自发对称破缺的简单模型 显示英文标题

标题： Simple models exhibiting spontaneous symmetry breakdown in classical and non-relativistic quantum mechanics

摘要： 首先，分析了一个经典自发对称破缺模型的性质。然后，讨论了一些用于说明自发对称破缺的教育性非相对论量子力学模型的优缺点。最后，提出一个简单的量子力学玩具模型（线上的旋量，具有自旋相关的相互作用），该模型展示了内部对称性的自发破缺。 显示英文摘要

摘要： First, the properties of a classical model of spontaneous symmetry breakdown are analyzed. Then, the pros and cons of some pedagogical non-relativistic quantum-mechanical models, also used to illustrate spontaneous symmetry breakdown, are discussed. Finally, a simple quantum-mechanical toy model (a spinor on the line, with a spin-dependent interaction) is presented, that exhibits the spontaneous breaking of an internal symmetry.