Counterexamples to Zariski’s multiplicity conjecture. Disproves Zariski's multiplicity conjecture by constructing reduced holomorphic hypersurface germs that are ambiently homeomorphic but have different multiplicities. The examples include hypersurfaces in ℂ4 with isolated critical points and multiplicities four and five.
released 2026-09-24 | 9 theorems · 11 lemmas · 20 proofs · 13,268 words |
PLAY LEVEL 1 »(pdf)
We give a negative answer to the embedded Zariski multiplicity conjecture. We construct two reduced hypersurface germs that are ambiently homeomorphic but have multiplicities two and three. Both have isolated singularities and lie in a common complex affine space of dimension divisible by eight. Their defining function germs are also topologically right equivalent, and the same examples answer Arnold's corank problem negatively for ambient topological equivalence.
released 2026-09-27 | 2 theorems · 18 lemmas · 21 proofs · 17,567 words |
PLAY LEVEL 2 »(pdf)
We give a negative answer to Zariski's multiplicity question in four complex variables. We construct two reduced convergent holomorphic function germs with isolated critical points and multiplicities four and five whose zero-set germs are ambiently homeomorphic.