English

121 Patchworked Curves of Degree Seven

Algebraic Geometry 2026-02-24 v2 Combinatorics

Abstract

The 121 real schemes, i.e., ambient isotopy classes, of smooth real plane algebraic curves of degree seven were classified by Viro (1984). By constructing one patchwork of the dilated triangle 7Δ27\cdot\Delta_2 for each real scheme, we provide an explicit method for constructing polynomials realizing each real scheme. In particular, every real scheme of degree seven can be realized as a T-curve; this settles a question raised by Itenberg and Viro (1996).

Keywords

Cite

@article{arxiv.2602.06888,
  title  = {121 Patchworked Curves of Degree Seven},
  author = {Zoe Geiselmann and Michael Joswig and Lars Kastner and Konrad Mundinger and Sebastian Pokutta and Christoph Spiegel and Marcel Wack and Max Zimmer},
  journal= {arXiv preprint arXiv:2602.06888},
  year   = {2026}
}

Comments

33 pages, 10 figures, 4 tables

R2 v1 2026-07-01T10:24:46.942Z