activity
20052023
most citedKernel functions and Bäcklund transformations for relativistic Calogero-Moser and Toda systems

28 citations · 117 across the 14 of their papers we have counts for

collaborators

18 papers

math-ph2023

Baxter -operator for the hyperbolic Calogero--Moser system

Martin Hallnäs

We introduce a -operator for the hyperbolic Calogero--Moser system as a one-parameter family of explicit integral operators. We establish the standard properties…

math.QA2022

New orthogonality relations for super-Jack polynomials and an associated Lassalle--Nekrasov correspondence

Martin Hallnäs

The super-Jack polynomials, introduced by Kerov, Okounkov and Olshanski, are polynomials in variables, which reduce to the Jack polynomials when or and provide jo…

math-ph2021★ 8 cited

Higher order deformed elliptic Ruijsenaars operators

Martin Hallnäs, Edwin Langmann, Masatoshi Noumi +1

We present four infinite families of mutually commuting difference operators which include the deformed elliptic Ruijsenaars operators. The trigonometric limit of this kind of oper…

math.QA2021★ 1 cited

From Kajihara's transformation formula to deformed Macdonald-Ruijsenaars and Noumi-Sano operators

Martin Hallnäs, Edwin Langmann, Masatoshi Noumi +1

Kajihara obtained in 2004 a remarkable transformation formula connecting multiple basic hypergeometric series associated with -type root systems of different ranks. By multiple…

math.QA2021★ 10 cited

Super-Macdonald polynomials: Orthogonality and Hilbert space interpretation

Farrokh Atai, Martin Hallnäs, Edwin Langmann

The super-Macdonald polynomials, introduced by Sergeev and Veselov, generalise the Macdonald polynomials to (arbitrary numbers of) two kinds of variables, and they are eigenfunctio…

math-ph2017★ 4 cited

Quantization and explicit diagonalization of new compactified trigonometric Ruijsenaars-Schneider systems

Tamás F. Görbe, Martin A. Hallnäs

Recently, Fehér and Kluck discovered, at the level of classical mechanics, new compactified trigonometric Ruijsenaars-Schneider -particle systems, with phase space symplectomorp…

math.SP2016★ 10 cited

On the Spectra of Real and Complex Lamé Operators

William A. Haese-Hill, Martin A. Hallnäs, Alexander P. Veselov

We study Lamé operators of the form with and a half-period of . For rectangular period lattices, we c…

math-ph2016

Joint eigenfunctions for the relativistic Calogero-Moser Hamiltonians of hyperbolic type. II. The two- and three-variable cases

Martin Hallnäs, Simon Ruijsenaars

In a previous paper we introduced and developed a recursive construction of joint eigenfunctions for the Hamiltonians of the hyperbolic relativistic Calogero-M…

math-ph2015★ 7 cited

Complex exceptional orthogonal polynomials and quasi-invariance

William A. Haese-Hill, Martin A. Hallnäs, Alexander P. Veselov

Consider the Wronskians of the classical Hermite polynomials where $k_i=λ_i+n-i,…

math.CA2015

Product formulas for the relativistic and nonrelativistic conical functions

Martin Hallnäs, Simon Ruijsenaars

The conical function and its relativistic generalization can be viewed as eigenfunctions of the reduced 2-particle Hamiltonians of the hyperbolic Calogero-Moser system and its rela…

math-ph2013★ 6 cited

A product formula for the eigenfunctions of a quartic oscillator

Martin Hallnäs, Edwin Langmann

We consider the Schrödinger operator on the real line with an even quartic potential. Our main result is a product formula of the type $ψ_k(x)ψ_k(y) = \int_{\mathbb{R}} ψ_k(z)\math…

math-ph2013★ 8 cited

Source identities and kernel functions for deformed (quantum) Ruijsenaars models

F. Atai, M. Hallnäs, E. Langmann

We consider the relativistic generalization of the quantum Calogero-Sutherland models due to Ruijsenaars, comprising the rational, hyperbolic, trigonometric and elliptic…

nlin.SI2013

A recursive construction of joint eigenfunctions for the hyperbolic nonrelativistic Calogero-Moser Hamiltonians

Martin Hallnäs, Simon Ruijsenaars

We obtain symmetric joint eigenfunctions for the commuting PDOs associated to the hyperbolic Calogero-Moser N-particle system. The eigenfunctions are constructed via a recursion sc…

math-ph2012★ 5 cited

Baker-Akhiezer functions and generalised Macdonald-Mehta integrals

M. V. Feigin, M. A. Hallnas, A. P. Veselov

For the rational Baker-Akhiezer functions associated with special arrangements of hyperplanes with multiplicities we establish an integral identity, which may be viewed as a genera…

nlin.SI2012

Joint eigenfunctions for the relativistic Calogero-Moser Hamiltonians of hyperbolic type. I. First steps

Martin Hallnäs, Simon Ruijsenaars

We present and develop a recursion scheme to construct joint eigenfunctions for the commuting analytic difference operators associated with the integrable N-particle systems of hyp…

nlin.SI2012★ 28 cited

Kernel functions and Bäcklund transformations for relativistic Calogero-Moser and Toda systems

Martin Hallnäs, Simon Ruijsenaars

We obtain kernel functions associated with the quantum relativistic Toda systems, both for the periodic version and for the nonperiodic version with its dual. This involves taking…

math-ph2007★ 23 cited

A unified construction of generalised classical polynomials associated with operators of Calogero-Sutherland type

Martin Hallnäs, Edwin Langmann

In this paper we consider a large class of many-variable polynomials which contains generalisations of the classical Hermite, Laguerre, Jacobi and Bessel polynomials as special cas…

math-ph2005★ 7 cited

Explicit formulas for the eigenfunctions of the N-body Calogero model

Martin Hallnäs, Edwin Langmann

We consider the quantum Calogero model, which describes N non-distinguishable quantum particles on the real line confined by a harmonic oscillator potential and interacting via two…