论文标题
结与反向之间的恢复距离
The cobordism distance between a knot and its reverse
论文作者
论文摘要
D(K,J)之间的COBORDISM距离等于四生G_4(K#-J)。我们考虑d(k,k^r),其中k^r是k的相反。这里表明,对于G_4(k)= g_3(k)的任何结(例如,具有G_3(k)= 1的非裂缝结或非常明显的准阳性结),一个人的D(k,k^r)严格少于两次G_4(k)。结果表明,对于任意正g,存在d(k,k^r)= g = g_4(k)的结。尚无d(k,k^r)> g_4(k)的已知示例。
The cobordism distance between knots, d(K,J), equals the four-genus g_4(K # -J). We consider d(K,K^r), where K^r is the reverse of K. It is elementary that 0 \le d(K,K^r) \le 2g_4(K) and it is known that there are knots K for which d(K,K^r) is arbitrarily large. Here it is shown that for any knot for which g_4(K) = g_3(K) (such as non-slice knots with g_3(K) = 1 or strongly quasi-positive knots), one has that d(K,K^r) is strictly less that twice g_4(K). It is shown that for arbitrary positive g, there exist knots for which d(K,K^r) = g = g_4(K). There are no known examples for which d(K,K^r) > g_4(K).