環圈














在环面上的二個環圈a及b


數學中的環圈（loop）是拓扑空间X上的连续函数f，其定義域為单位区间I = [0,1]，而且f(0) = f(1)。換句話說，環圈是拓扑學中，起點和終點相同的道路[1]。



相關條目



  • 基本群

  • 拟群

  • 環 (圖論)



參考資料





  1. ^ Adams, John Frank, Infinite Loop Spaces, Annals of mathematics studies 90, Princeton University Press: 3, 1978, ISBN 9780691082066 .




KleinBottle-01.png  環圈是一个关于拓扑学的小作品。你可以通过编辑与修订扩充其内容。







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