Abstract:
The Pell–Abel (PA) functional equation is the reincarnation of the famous Diophantine equation in the world of polynomials, considered N. H. Abel in 1826. The equation arises in many problems: reduction of Abelian integrals, elliptic billiards, the spectral problem for infinite Jacobi matrices, approximation theory, etc. If the PA equation has a nontrivial solution, then there are infinitely many of them, and all of them are expressed via a primitive solution having a minimum degree. Using graphical techniques, we find the number of connected components in the space of PA equations with the coefficient of a given degree and having a primitive solution of another given degree.
Joint work with Quentin Gendron (UNAM Institute of Mathematics) https://arxiv.org/abs/2306.00884.