English

Leading terms of generalized Pl\"ucker formulas

Algebraic Geometry 2024-06-26 v2

Abstract

Generalized Pl\"ucker numbers are defined to count certain types of tangent lines of generic degree dd complex projective hypersurfaces. They can be computed by identifying them as coefficients of GL(2)-equivariant cohomology classes of certain invariant subspaces, the so-called coincident root strata, of the vector space of homogeneous degree dd complex polynomials in two variables. In an earlier paper L\'aszl\'o M. Feh\'er and the author gave a new, recursive method for calculating these classes. Using this method, we showed that -- similarly to the classical Pl\"ucker formulas counting the bitangents and flex lines of a degree dd plane curve -- generalized Pl\"ucker numbers are polynomials in the degree dd. In this paper, by further analyzing our recursive formula, we determine the leading terms of all the generalized Pl\"ucker formulas.

Keywords

Cite

@article{arxiv.2404.18859,
  title  = {Leading terms of generalized Pl\"ucker formulas},
  author = {András P. Juhász},
  journal= {arXiv preprint arXiv:2404.18859},
  year   = {2024}
}

Comments

21 pages, 6 figures; typos corrected