XLIII Workshop on Geometric Methods in Physics Białystok, 29.06–4.07.2026 XV School on Geometry and Physics Białystok, 22–26.06.2026

Krzysztof Marciniak


Stäckel systems, soliton hierarchies and Painlevé-type systems


The aim of this lecture series is to present a completely new perspective on the relationships between three major classes of integrable systems: classical separable (in the sense of Hamilton–Jacobi theory) Stäckel systems, soliton hierarchies, and Painlevé‑type systems.

I begin by examining how deformations of Stäckel‑separable systems, constructed via suitable algebras of Killing tensors, give rise to both known and new Painlevé‑type equations. I then demonstrate - using the coupled Korteweg–de Vries hierarchy as a guiding example - how appropriate autonomous constraints reduce a soliton hierarchy to a corresponding Stäckel system, highlighting the way in which the geometric structures inherent in the hierarchy manifest themselves in the resulting Stäckel system. Finally, (this part is not yet published), I discuss how suitable non‑autonomous constraints allow one to reduce a soliton hierarchy to a Painlevé‑type system. Thus, a new and complete picture of relations between these three large classes of integrable systems emerges.

The lectures will be self‑contained and will include all necessary definitions and background information.
Event sponsored by
University of Białystok
University of Białystok