Semigroups,<i>d</i>-invariants and deformations of cuspidal singular points of plane curves
Semigroups,<i>d</i>-invariants and deformations of cuspidal singular points of plane curves
We study δ-constant deformations of plane curve singularities from a topological point of view. We introduce a topological counterpart to a δ-constant deformation in singularity theory. Methods from Heegaard Floer theory give a purely topological proof of the semicontinuity property for semigroups of singular points of plane curves under δ-constant …