On the Alexander polynomials of Hurwitz curves

Alexander modules of irreducible $C$-groups

A complete description of the Alexander modules of knotted $n$-manifolds in the sphere $S^{n+2}$, $n\geq 2$, and irreducible Hurwitz curves is given. This description is applied to investigate properties of the first homology groups of cyclic coverings of the sphere $S^{n+2}$ and the projective complex plane $\mathbb C\mathbb P^2$ branched respectively alone knotted $n$-manifolds and along irreducible Hurwitz (in particular, algebraic) curves.

D-branes of A-type, their deformations, and Morse cobordism of A-branes on Calabi-Yau 3-folds under a split attractor flow: Donaldson/Alexander-Hilden-Lozano-Montesinos-Thurston/Hurwitz/Denef-Joyce meeting Polchinski-Grothendieck

In [L-Y5] (D(6): arXiv:1003.1178 [math.SG]) we introduced the notion of Azumaya $C^{\infty}$-manifolds with a fundamental module and morphisms therefrom to a complex manifold. In the current sequel, we use this notion to give a prototypical definition of supersymmetric D-branes of A-type (i.e. A-branes) -- in an appropriate region of the Wilson's theory-space of string theory -- as special Lagrangian morphisms from such objects with a unitary, minimally flat connection-with-singularities. This merges Donaldson's picture of special Lagrangian submanifolds and the Polchinski-Grothendieck Ansatz …

On the fundamental groups of the complements of Hurwitz curves

It is proved that the commutator subgroup of the fundamental group of the complement of any plane affine irreducible Hurwitz curve (respectively, any plane affine irreducible pseudoholomorphic curve) is finitely presented. It is shown that there exists a pseudo-holomorphic curve (a Hurwitz curve) in $\mathbb C\mathbb P^2$ whose fundamental group of the complement is not Hopfian and, respectively, this group is not residually finite. In addition, it is proved that there exist an irreducible nonsingular algebraic curve $C\subset \mathbb C^2$ and a bi-disk $D\subset \mathbb C^2$ such that the fun…

辛曲线的Oka和Alexander多项式及可除性关系

Oka and Alexander polynomials of symplectic curves and divisibility relations

本文研究了辛曲线的Oka和Alexander多项式，并证明了其在复射影平面上的可除性关系，同时给出了复杂代数曲线相关多项式的新证明。

Regular homotopy of Hurwitz curves

We prove that any two irreducible cuspidal Hurwitz curves $C_0$ and $C_1$ (or more generally, curves with A-type singularities) in the Hirzebruch surface $F_N$ with coinciding homology classes and sets of singularities are regular homotopic; and symplectically regular homotopic if $C_0$ and $C_1$ are symplectic with respect to a compatible symplectic form.

Links and Hurwitz curves

In the note, we give a proof, based on the Generalized Thom Conjecture, of Bennequin's Theorem on upper bound for the Euler number of a link which is considered as a closed braid. A lower bound for the Euler number of a link is also given.