The paper discusses current theories of melting of two-dimensional systems that are mainly based on the concepts of the Berezinskii–Kosterlitz–Thouless (BKT) theory of phase transitions in two-dimensional systems with continuous symmetry. At present there are three basic scenarios of melting of two-dimensional crystals that as shown by computer simulation are implemented in the two-dimensional system of Hertzian spheres used to describe the behavior of a number of soft matter systems. The system demonstrates complex phase behavior with the presence of all three melting scenarios in the various parts of the phase diagram.

中文翻译：

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二维系统的Berezinskii–Kosterlitz–Thouless过渡和熔化场景

本文讨论了当前的二维系统熔化理论，这些理论主要基于具有连续对称性的二维系统中相变的贝雷津斯基-科斯特里茨-图莱斯（BKT）理论。目前，存在三种熔化二维晶体的基本方案，如计算机模拟所示，该方案在用于描述许多软物质系统行为的赫兹球二维系统中实现。该系统演示了复杂的相行为，并且在相图的各个部分中存在所有三种熔化情况。