Non-complex cobordisms between quasipositive knots
Geometric Topology
2025-12-25 v3
Abstract
We show that for every genus , there exist quasipositive knots and such that there is a cobordism of genus between and , but there is no ribbon cobordism of genus in either direction and thus no complex cobordism between these two knots. This gives a negative answer to a question posed by Feller in 2016.
Keywords
Cite
@article{arxiv.2504.04894,
title = {Non-complex cobordisms between quasipositive knots},
author = {Maciej Borodzik and Paula Truöl},
journal= {arXiv preprint arXiv:2504.04894},
year = {2025}
}
Comments
13 pages, 5 figures, 1 table. Comments welcome! v3: More details and improved exposition following the referee's comments. Section 5 added, along with 5 figures. Corresponds to version accepted for publication in J. Math. Pures Appl