Research

Orthogonal polynomials, symmetric functions, spectral methods, and integrable models.

Current Research

My research focuses on orthogonal polynomials and symmetric functions, especially Hall–Littlewood and Koornwinder-type structures, and their applications to spectral theory, probability, and integrable models.

I am particularly interested in stochastic models on partitions and discrete state spaces whose transition operators admit explicit spectral descriptions, with emphasis on orthogonality, boundary parameters, spectral data, and long-time behavior.

I also study exactly solvable models in mathematical physics, including quantum spin chains and finite random walks, where special-function methods provide explicit eigenfunctions and transition formulas.

Research Outputs

2026
The Spectrum of the Finite Open XX Quantum Spin Chain with Transverse Magnetic Boundary Fields via Orthogonal Polynomials
Jan Felipe van Diejen, Andrés Soledispa Tibán, Adrián Vidal
Published. Annales Henri Poincaré 27(4), 1451–1495 (2026). Online publication: April 2025.
2026
Approximation of Askey–Wilson roots
Jan Felipe van Diejen, Andrés Soledispa Tibán, Adrián Vidal
Published. Constructive Approximation (2026). Online publication: 11 October 2026.

Computational Tools

HHL Lab