English

On the reconstruction problem for Pascal lines

Algebraic Geometry 2019-11-18 v1

Abstract

Given a sextuple of distinct points A,B,C,D,E,FA, B, C, D, E, F on a conic, arranged into an array [ABCFED]\left[\begin{array}{ccc} A & B & C F & E & D \end{array}\right], Pascal's theorem says that the points AEBF,BDCE,ADCFAE \cap BF, BD \cap CE, AD \cap CF are collinear. The line containing them is called the Pascal of the array, and one gets altogether sixty such lines by permuting the points. In this paper we prove that the initial sextuple can be explicitly reconstructed from four specifically chosen Pascals. The reconstruction formulae are encoded by some transvectant identities which are proved using the graphical calculus for binary forms.

Cite

@article{arxiv.1608.05056,
  title  = {On the reconstruction problem for Pascal lines},
  author = {Abdelmalek Abdesselam and Jaydeep Chipalkatti},
  journal= {arXiv preprint arXiv:1608.05056},
  year   = {2019}
}

Comments

24 pages, 37 figures

R2 v1 2026-06-22T15:22:38.700Z