2025/04/07 by Borodzik, Maciej, Truöl, Paula · 1 citation
#57K10 (Primary) 14H50 (Secondary) #FOS: Mathematics #Geometric Topology (math.GT)
paper · doi:10.48550/arxiv.2504.04894
We show that for every genus g ≥ 0, there exist quasipositive knots K0g and K1g such that there is a cobordism of genus g=|g4(K1g)-g4(K0g)| between K0g and K1g, but there is no ribbon cobordism of genus g 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.