复合形在欧氏空间中的同痕问题（Ⅰ）
On the isotopy of a complex in a Euclidean space (ⅰ)
如果一个圈与某个群同痕，那么它与此群同构，因此也为一个群。
If a loop is isotopic to a group , then it is isomorphic to that group and thus is itself a group .
同痕