arXivDaily arXiv每日学术速递 周一至周五更新
arXiv math/9907172math.GT
收藏

虚拟纽结群

Virtual Knot Groups

Se-Goo Kim

摘要:

考夫曼定义的虚结是经典结的自然推广。结的大多数不变量以自然的方式扩展以给出虚拟结的不变量。在本文中,我们研究了虚纽结的基本群,并观察到一些新的和意想不到的现象。在经典的设定中,如果一个纽结的经度在纽结群中是平凡的,那么这个群是无限循环的。我们证明了对于任何经典的纽结群,都存在一个具有该群和平凡经度的虚纽结。众所周知,经典纽结群的第二同调是平凡的。我们提供了反例,这虚拟结。对任意群G,给出了存在一个虚纽结群的充要条件,该群在G的周边子群上具有特定的行为.这些条件简化了经典环境中出现的条件。

英文摘要:

Virtual knots, defined by Kauffman, provide a natural generalization of classical knots. Most invariants of knots extend in a natural way to give invariants of virtual knots. In this paper we study the fundamental groups of virtual knots and observe several new and unexpected phenomena. In the classical setting, if the longitude of a knot is trivial in the knot group then the group is infinite cyclic. We show that for any classical knot group there is a virtual knot with that group and trivial longitude. It is well known that the second homology of a classical knot group is trivial. We provide counterexamples of this for virtual knots. For an arbitrary group G, we give necessary and sufficient conditions for the existence of a virtual knot group that maps onto G with specified behavior on the peripheral subgroup. These conditions simplify those that arise in the classical setting.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑