English

The algebraic square peg problem

Algebraic Geometry 2014-03-25 v1 Algebraic Topology Combinatorics

Abstract

The square peg problem asks whether every continuous curve in the plane that starts and ends at the same point without self-intersecting contains four distinct corners of some square. Toeplitz conjectured in 1911 that this is indeed the case. Hundred years later we only have partial results for curves with additional smoothness properties. The contribution of this thesis is an algebraic variant of the square peg problem. By casting the set of squares inscribed on an algebraic plane curve as a variety and applying Bernshtein's Theorem we are able to count the number of such squares. An algebraic plane curve defined by a polynomial of degree m inscribes either an infinite amount of squares, or at most (m^4 - 5m^2 + 4m)/4 squares. Computations using computer algebra software lend evidence to the claim that this upper bound is sharp for generic curves.

Keywords

Cite

@article{arxiv.1403.5979,
  title  = {The algebraic square peg problem},
  author = {Wouter van Heijst},
  journal= {arXiv preprint arXiv:1403.5979},
  year   = {2014}
}

Comments

63 pages, 29 figures. This Master's thesis contains the complete results referred to in the Notices of the AMS, April 2014, p 349

R2 v1 2026-06-22T03:32:54.956Z