arXiv subjects

Aleksey Zinger

Publications and source records attributed to Aleksey Zinger.

58 records · Page 4Linked to original sources

arXiv2005

On the Genus-One Gromov-Witten Invariants of a Quintic Threefold

We rederive a relation between the genus-one GW-invariants of a quintic threefold in $\Pf$ and the genus-zero and genus-one GW-invariants of $\Pf$. In contrast to the more general derivation in a separate paper, the present derivation relies on a widely believed, but still unproven, statement concerning rigidity of holomorphic curves in Calabi-Yau threefolds. On the other hand, this paper's derivation is more direct and geometric. It requires a bit more effort, but relies on less outside work.

math.AG↗

arXiv2005

On the Genus-One Gromov-Witten Invariants of Complete Intersections

As shown in a previous paper, certain naturally arising cones of holomorphic vector bundle sections over the main component $\ov\M_{1,k}^0(¶,d)$ of the moduli space of stable genus-one holomorphic maps into $¶$ have a well-defined euler class. In this paper, we extend this result to moduli spaces of perturbed, in a restricted way, $J$-holomorphic maps. We show that euler classes of such cones relate the reduced genus-one Gromov-Witten invariants of complete intersections to the corresponding GW-invariants of the ambient projective space. As a consequence, the standard genus-one GW-invariants of complete intersections can be expressed in terms of the genus-zero and genus-one GW-invariants of projective spaces. We state such a relationship explicitly for complete-intersection threefolds. A relationship for higher-genus invariants is conjectured as well.

math.AG↗

arXiv2005

Counting Plane Rational Curves: Old and New Approaches

These notes are intended as an easy-to-read supplement to part of the background material presented in my talks on enumerative geometry. In particular, the numbers $n_3$ and $n_4$ of plane rational cubics through eight points and of plane rational quartics through eleven points are determined via the classical approach of counting curves. The computation of the latter number also illustrates my topological approach to counting the zeros of a fixed vector bundle section that lie in the main stratum of a compact space. The arguments used in the computation of the number $n_4$ extend easily to counting plane curves with two or three nodes, for example. Finally, an inductive formula for the number $n_d$ of plane degree-$d$ rational curves passing through $3d-1$ points is derived via the modern approach of counting stable maps.

math.AG↗

arXiv2005

Counting rational curves of arbitrary shape in projective spaces

We present an approach to a large class of enumerative problems concerning rational curves in projective spaces. This approach uses analysis to obtain topological information about moduli spaces of stable maps. We demonstrate it by enumerating one-component rational curves with a triple point or a tacnodal point in the three-dimensional projective space and with a cusp in any projective space.

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