共变














































































































共变（共变性）可指：



  • 共变函子

  • 共变张量场

  • 共变导数


  • 共变和反变（数学）

  • 洛伦兹协变性


协变可以指：



  • 协变和逆变（计算机科学）

其对偶概念为反变。













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