activity
20202026
most citedHolographic transform for tensor product of holomorphic discrete series

2 citations · 3 across the 17 of their papers we have counts for

collaborators

22 papers

math.RT2026

Continuous representations of the meta Hahn algebra and special functions

Quentin Labriet, Luc Vinet

Infinite families of biorthogonal rational functions are constructed using infinite dimensional representations of the three-generated meta Hahn algebra. Continuous Hahn and contin…

math-ph2026

Para families of orthogonal polynomials

Stéphane Z. Beaulac, Nicolas Crampé, Quentin Labriet +3

The para-Krawtchouk polynomials arose in the search for spin chains with perfect state transfer; the para-Racah, -para-Racah and para-Bannai--Ito polynomials followed, obtained…

math-ph2026

The supersymmetric Scarf I Hamiltonian with reflections and its discrete para-Bannai--Ito version

Stéphane Z. Beaulac, Nicolas Crampé, Quentin Labriet +3

The para-Bannai--Ito polynomials are orthogonal on a Bannai--Ito bi-lattice that is \emph{two-sided} --- it extends on both sides of a central value --- and depend, besides t…

math-ph2026

The para--Racah Hamiltonian as an exactly solvable discretization of the Pöschl--Teller box

Stéphane Z. Beaulac, Nicolas Crampé, Quentin Labriet +3

The para-Racah polynomials, taken at the persymmetric value of their isospectral deformation parameter, define through their recurrence relation a mirror-symmetric tridiagonal Hami…

math-ph2026

The para--Krawtchouk oscillator and its continuum limit

Stéphane Z. Beaulac, Nicolas Crampé, Quentin Labriet +3

The para-Krawtchouk polynomials define, through their recurrence relation, a finite oscillator model that exhibits fractional revival. We determine the continuum limit of this Hami…

cond-mat.str-el2026

Universal scaling of spatially extended zero modes in inhomogeneous SSH chains

Gilles Parez, Nicolas Crampé, Quentin Labriet +2

Protected zero modes are a hallmark of topological phases of matter and are exponentially localized at sharp interfaces between distinct gapped phases. We investigate how this pict…

math-ph2026

Algebraic Leonard trio approach to rational functions: the Hahn case

Nicolas Crampé, Quentin Labriet, Lucia Morey +1

The finite families of Hahn polynomials and associated biorthogonal rational functions are interpreted algebraically in the framework of Leonard trios. We introduce the trio Hahn a…

math-ph2026

The dynamical algebra of the generic superintegrable model on the two-sphere

Nicolas Crampé, Quentin Labriet, Lucia Morey +3

The rank two Jacobi algebra is identified as the dynamical algebra of the generic quadratic superintegrable model on the two-sphere. The physical representation of…

math.CA2026

Meta Algebras and Special Functions: the Racah Case

Nicolas Crampé, Quentin Labriet, Lucia Morey +3

Finite families of biorthogonal rational functions and orthogonal polynomials of Racah-type are studied within a unified algebraic framework based on the meta Racah algebra and its…

math.RT2026

Exceptional theta correspondences via Plancherel formulas for rank one symmetric spaces

Jan Frahm, Quentin Labriet

We consider the minimal representation of (a finite cover of) the conformal group of a simple split Jordan algebra over or , whenever it exists. The confor…

math.RA2026

Bispectral rational functions and Leonard trios

Nicolas Crampé, Wolter Groenevelt, Quentin Labriet +3

It is well-known that Leonard pairs have a close connection with bispectral orthogonal polynomials of the Askey scheme. In this paper, we introduce the notion of a Leonard trio $(V…

math-ph2025★ 1 cited

Inhomogeneous SSH models and the doubling of orthogonal polynomials

Nicolas Crampé, Quentin Labriet, Lucia Morey +2

We analyze Su-Schrieffer-Heeger (SSH) models using the doubling method for orthogonal polynomial sequences. This approach yields the analytical spectrum and exact eigenstates of th…

math.CA2025

Algebraic interpretation of discrete families of matrix valued orthogonal polynomials

Quentin Labriet, Lucia Morey, Luc Vinet

An algebraic interpretation of matrix-valued orthogonal polynomials (MVOPs) is provided. The construction is based on representations of a (-deformed) Lie algebra …

math.RT2025

Algebraic interpretation of the two-variable Jacobi polynomials on the triangle: the pentagonal way

Nicolas Crampé, Quentin Labriet, Lucia Morey +3

The rank two Jacobi algebra is used to provide an interpretation of the two-variable Jacobi polynomials on the triangle, as overlaps betwee…

math-ph2025

Exactly solvable inhomogeneous XY spin chain

Pierre-Antoine Bernard, Nicolas Crampé, Quentin Labriet +2

Analytical expressions for the eigenvalues of certain inhomogeneous XY spin chains are computed. These models are rewritten in terms of free-fermion models using a well-known Jorda…

math.RT2025

Little -Jacobi polynomials and symmetry breaking operators for

Quentin Labriet, Loïc Poulain d'Andecy

This paper presents explicit formulas for intertwining operators of the quantum group acting on tensor products of Verma modules. We express a first set of intertwining…

math.RT2025

Differential symmetry breaking operators for the pair

Jonathan Ditlevsen, Quentin Labriet

In this article we study differential symmetry breaking operators between principal series representations induced from minimal parabolic subgroups for the pair $(\operatorname{GL}…

math.RT2023

Identities for Rankin-Cohen brackets, Racah coefficients and associativity

Quentin Labriet, Loic Poulain d'Andecy

We prove an infinite family of identities satisfied by the Rankin-Cohen brackets involving the Racah polynomials. A natural interpretation in the representation theory of sl(2) is…

math.RT2023

Realisations of Racah algebras using Jacobi operators and convolution identities

Q. Labriet, L. Poulain d'Andecy

Using the representation theory of sl(2) and an appropriate model for tensor product of lowest weight Verma modules, we give a realisation first of the Hahn algebra, and then of th…

math.RT2023

Restricting holomorphic discrete series representations to a compact dual pair

Jan Frahm, Quentin Labriet

The goal of this article is to study the branching problem for a holomorphic discrete series representation of the conformal group of a simple Euclidean Jordan algebra restrict…

math.RT2022

A geometrical point of view for branching problems for holomorphic discrete series of conformal Lie groups

Quentin Labriet

This article is devoted to branching problems for holomorphic discrete series representations of a conformal group of a tube domain over a symmetric cone . More pr…

math.CA2020★ 2 cited

Holographic transform for tensor product of holomorphic discrete series

Quentin Labriet

We study holographic operators associated with Rankin-Cohen brackets which are symmetry breaking operators for the restriction of tensor products of holomorphic discrete series of…