2 papers
math.GT2025
When is arc crossing change an unknotting operation?
Zhiyun Cheng, Qian Liao, Jingze Song
This paper extends the study of arc crossing change, a local operation on knot diagrams recently introduced by Cericola, from knot diagrams to link diagrams. We consider two types…
math.GT2025
Region crossing change on nonorientable surfaces
Zhiyun Cheng, Jingze Song
In this paper, we give a classification of link diagrams on nonorientable surfaces up to region crossing changes.