从物理学角度，本文简要介绍凝聚态物质系统中拓扑缺陷的概念，并阐述拓扑缺陷如何深刻影响各类凝聚态系统的相变和集体行为等问题.
From the perspective of physics, this paper presents an introduction to the concept of topological defect in condensed matter systems, and illustrates the fundamental role of topological defects on phase transitions and collective behaviors of condensed matters.
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