English

Poncelet porism in singular cases

Algebraic Geometry 2025-07-08 v2 Exactly Solvable and Integrable Systems

Abstract

The celebrated Poncelet porism is usually studied for a pair of smooth conics that are in a general position. Here we discuss Poncelet porism in the real plane - affine or projective, when that is not the case, i.e. the conics have at least one point of tangency or at least one of the conics is not smooth. In all such cases, we find necessary and sufficient conditions for the existence of an n-gon inscribed in one of the conics and circumscribed about the other.

Keywords

Cite

@article{arxiv.2504.21514,
  title  = {Poncelet porism in singular cases},
  author = {Vladimir Dragovic and Milena Radnovic},
  journal= {arXiv preprint arXiv:2504.21514},
  year   = {2025}
}

Comments

16 pages, 11 figures

R2 v1 2026-06-28T23:16:36.083Z