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I’m a research fellow in mathematical physics at the University of Melbourne. I work on quantum integrability somewhere in between theoretical physics and mathematics. For me this means combining motivation, interpretation and intuition from the former with the powerful analytical techniques, deep structural understanding and elegance from the latter in order to push the boundaries of both.
On this website you can read about my research interests, publications, past and upcoming presentations, teaching and supervision and more.
You can reach me at jules⊗l⊕unimelb⊗edu⊗au or
School of Mathematics and Statistics
University of Melbourne, VIC 3010
Australia
Before moving down under, I was a postdoc in the group of Hjalmar Rosengren at the department of mathematics of Chalmers and the University of Gothenburg.
Prior to that, I was a PhD candidate at the Institute for Theoretical Physics of Utrecht University, supervised by Gleb Arutyunov and informally cosupervised by André Henriques.
See also my profiles on StackExchange and Google scholar or my CV.
Last update: 18 May ’21
My research focusses on quantum integrability in the contexts of
 Quantum spin chains with longrange interactions (Heisenberg, Inozemtsev, Haldane–Shastry),
 Quantum manybody systems (Calogero–Sutherland, Ruijsenaars),
 Classical statisticalmechanical lattice models (sixvertex, elliptic solidonsolid),
as well as the associated
 Quantum algebra (quantum groups, affine Hecke algebras),
 Diagrammatic methods (a picture is worth a thousand words), and
 Orthogonal polynomials (Jack, Macdonald).
More broadly I am interested in mathematical physics: the interplay between mathematics and theoretical physics. This includes quantum field theory, both ordinary and supersymmetric (I like N=2); in fact, that is where my interest in quantum integrability started: see my MSc thesis for theoretical physics.
See also the events that I have participated in or check out my questions and answers on MathOverflow, Mathematica.SE and other StackExchange sites.
Last update: 18 Oct ’20
Below you can find an overview of my publications. See also my profiles at arXiv, Google scholar, INSPIRE and ORCID.
As you can see, so far I have joint publications with Gerard Barkema, Rembert Duine, Wellington Galleas, Rick Keesman (2x), Rob Klabbers, Yuan Miao, Vincent Pasquier (2x) and Didina Serban.
2020
 Y Miao, JL and V Pasquier, On the Q operator and the spectrum of the XXZ model at root of unity, arXiv:2012.10224
 R Klabbers and JL, How coordinate Bethe ansatz works for Inozemtsev model, arXiv:2009.14513
 JL, V Pasquier and D Serban, SpinRuijsenaars, qdeformed HaldaneShastry and Macdonald polynomials, arXiv:2004.13210
2018
 JL, The functional method for the domainwall partition function, SIGMA 14 (2018) 064, arXiv:1801.09635
 JL, Resurrecting the partially isotropic Haldane–Shastry model, Phys Rev B 97 (2018) 214416, arXiv:1801.05728
2017
 R Keesman and JL, A numerical study of the Fmodel with domainwall boundaries, Phys Rev E 95 (2017) 052117, arXiv:1702.05474
2016
 JL, On elliptic quantum integrability: vertex models, solidonsolid models and spin chains, PhD thesis (2016)
 R Keesman, JL, R A Duine and G T Barkema, Finitesize scaling at infiniteorder phase transitions, J Stat Mech: Theor Exp 2016 (2016) 093201, arXiv:1605.08876
2015
 JL, Integral formula for elliptic SOS models with domain walls and a reflecting end, Nucl Phys B 901 (2015) 556, arXiv:1510.00342
2014
 JL, A pedagogical introduction to quantum integrability, with a view towards theoretical highenergy physics, PoS Modave2014 (2014) 001, arXiv:1501.06805
 W Galleas and JL, Reflection algebra and functional equations, Nucl Phys B 886 (2014) 1003, arXiv:1405.4281
Earlier
My BSc and MSc theses can be found at CV.
Last update: 1 Apr ’21
Below you can find an overview of my upcoming and past presentations, in antichronological order. See also my pedagogical experience, other activities I have been involved with, and a list with all events that I have participated in.
Upcoming

Conference on applications of Macdonald polynomials, Indian Institute of Science, Bengaluru (19 – 23 July ’21) [zoom]
Recent
 Two other scalar products (~ Section VI.9 of Macdonald)
Macdonald reading group, U Melbourne (weekly, 17–24 May ’21) [zoom, notes]  Schur–Weyl duality for Yangians and quantum affine algebras (roughly following Section 12.3 of Chari–Pressley)
Quantum algebra reading group, Nordita (weekly, 24 March – 26 May ’21) [zoom]  Recent advances for integrable longrange spin chains
Pure math seminar, U NSW (14 Jun ’21) [zoom, slides]
Mathematical physics seminar, U Melbourne (18 May ’21) [slides]
Student workshop on integrability, online (26 Apr ’21) [zoom, slides]
Condensed matter theory seminar, U of Amsterdam (6 Apr ’21) [zoom, slides]
Pure mathematics seminar, U Queensland (17 Feb ’21) [slides]
Mathematical physics session, AustMS (9 Dec ’20) [zoom, slides]  Macdonald operators (~ Section VI.3 of Macdonald)
Macdonald reading group, U Melbourne (weekly, 8–15 Feb ’21) [zoom, notes part one part two]  An invitation to spin chains and quantum integrability
Three W’s seminar, KIAS, Korea (9 Nov ’20) [zoom, slides]  How coordinate Bethe ansatz works for Inozemtsev model
New Connections in Integrable Systems, U Queensland (30 Sep ’20) [zoom, slides, video]  SpinRuijsenaars, qdeformed Haldane–Shastry and Macdonald polynomials
Nordita integrability journal club (16 and 23 June ’20) [zoom, slides]
Analysis and Probability seminar, Chalmers (19 May ’20) [zoom]
Seminar of the Edinburgh mathematical physics group (13 May ’20) [zoom]  A fresh look at Inozemtsev’s elliptic spin chain
Baxter 2020: Frontiers in Integrability, Australian National U, Canberra (12 Feb ’20) [slides]  The qdeformed Haldane–Shastry spin chain: from the affine Hecke algebra, via ‘freezing’, to exact eigenvectors
New trends in integrable systems, Osaka City U, Japan (18 Sep ’19) [slides]
Integrable systems seminar, U Leeds, UK (13 Sep ’19)
Elliptic integrable systems, special functions and quantum field theory, Nordita, Stockholm (16 June ’19)
Joint pure maths and mathematical physics seminar, UQ Brisbane (17 May ’19)
Math phys seminar, U Melbourne (30 Apr ’19)
Longer ago
 An exactly solvable longrange spin chain: the qdeformed Haldane–Shastry model
Virginia Integrable Probability Summer School 2019, U Virginia, Charlottesville VA (7 June ’19)
ANZAMP Annual Meeting 2019, Merimbula, NSW (5 Feb ’19) [slides]  An update on the qdeformed Haldane–Shastry model
Mathematical physics seminar, IPhT CEA Saclay (17 Sep ’18) [video]  The qanalogue of the Haldane–Shastry spin chain
Theoretical physics seminar, Trinity College Dublin (10 July ’18)
Correlation functions in exactly solvable models, Nordita, Stockholm (5 June ’18)  Quantum spin chains: the quantumintegrable perspective
and What is a quantum group (and why care)?
Workshop on probabilistic approaches to quantum spin systems, Gothenburg (17 and 20 Apr ’18)  Resurrecting the qanalogue of the Haldane–Shastry spin chain
Mathematical physics seminar, U Melbourne (27 Mar ’18) [slides]
Strings, integrability and beyond, IPhT CEA Saclay (14 Feb ’18)
String theory seminar, DESY Hamburg (30 Jan ’18)
Poster session, Young Researchers Integrability School and Workshop, Monte Verità, Ascona (7 Jan ’18) [poster], awarded a honourable mention for poster contribution  Resurrecting the partially isotropic Haldane–Shastry model
Condensed matter theory seminar, U of Amsterdam (20 Dec ’17)
Group of Prof Essler, Condensed matter theory, Oxford U (7 Dec ’17)
Strings, cft & integrability seminar, ETH Zürich (14 Nov ’17)  The structure of the temperate region of the Fmodel with domainwall boundaries
Student session, Exact methods in low dimensional statistical physics, Cargèse (29 July ’17) [slides]
Geometry, physics and probability seminar, U C Louvain, LouvainlaNeuve (20 Apr ’17) [blackboard + slides]
KTH/Nordita/SU seminar in theoretical physics, Stockholm (8 Feb ’17)  The constructive method for the elliptic solidonsolid model with domain walls and a reflecting end
Poster session, Elliptic hypergeometric functions in combinatorics, integrable systems and physics, ESI Vienna (20 Mar ’17) [poster]  Constructive method for the domainwall partition function
Analysis and probability seminar, Chalmers, Gothenburg (13 Dec ’16)
Student session, Les Houches Summer School on Integrability, Les Houches (22 June ’16) [video]  On elliptic quantum integrability: vertex models, solidonsolid models and spin chains
PhD defense, Utrecht U (1 June ’16)
PhD thesis talk, Institute for Theoretical Physics, Utrecht (30 May ’16) [slides]  Functional equations for elliptic SOS models with domain walls and a reflecting end
Analysis and probablility seminar, Chalmers, Gothenburg (12 Nov ’15) [slides]
Representation theory seminar, U of Amsterdam (16 Oct ’15)
DESY Theory Workshop, DESY Hamburg (30 Sep ’15) [slides]  Differential approach to onshell scalar products
Poster session, IGST, Imperial College London, UK (July ’15)  Ice: an introduction to the sixvertex model
Student seminar, NIKHEF theory meeting, Amsterdam (26 June ’15)
PLaneT seminar, Institute for Theoretical Physics, Utrecht U (23 June ’15)  Functional equations from the reflection algebra
Poster session, Trends in theory, Dalfsen (29 May ’15)
Poster session, IGST, DESY Hamburg, and Summer school on quantum groups and integrability, U Hamburg (July ’14) [poster]  Kramers–Wannier duality for a twodimensional square lattice
Advanced graduate seminar, Utrecht U (7 and 31 Mar ’14)  Algebraic aspects of the Berezinian
MSc thesis talk, Mathematical Institute, Utrecht U (14 Sep ’12)  The Bethe/gauge correspondence: a mysterious link between quantum integrability and supersymmetric gauge theories
MSc thesis talk, Institute for Theoretical Physics, Utrecht U (26 June ’12)
Last update: 18 Jun ’21
I am the cosupervisor of Paul ZinnJustin’s PhD student Ajeeth Gunna. Recently I remotely cosupervised Rob Klabber’s MSc student Simon Lentz (KTH Stockholm). I am also the cosupervisor of Hjalmar Rosengren’s PhD student Linnea Hietala (Chalmers and University of Gothenburg), see also here.
Below you can find a more detailed description of my pedagogical experience. See also these other activities that I have been involved in.
Melbourne
For simplicity I keep using the seasons of the Northern hemisphere.
 Fall 2020–Spring 2021: cosupervising Rob Klabber’s MSc student Simon Lentz (KTH Stockholm)
 Spring 2020–present: cosupervising Paul ZinnJustin’s PhD student Ajeeth Gunna
 Fall 2019: assisting the MSc course Exactly Solvable Models taught by Paul ZinnJustin
 Spring 2019: teaching assistant for Schur functions and Schur processes, taught by Ole Warnaar, and Quantum integrability and symmetric polynomials taught by Paul ZinnJustin at the Virginia Integrable Probability Summer School 2019
Chalmers
 Fall 2016–present: cosupervising Hjalmar Rosengren’s PhD student Linnea Hietala, see also here
 Spring 2017: Quantum and classical particle systems, together with Jakob Björnberg
Utrecht U
As a PhD candidate
 Spring 2014–winter 2015: Seminar on mathematical aspects of QFT, organised together with PhD candidates from the Mathematical Institute at Utrecht U
 Summer 2014: Introduction to quantum integrability at the Modave summer school in mathematical physics, Modave (summer 2014) [lecture notes]
 Spring 2014: Introduction to higherspin gauge theory, taught by Kramers Professor Mikhail Vasiliev from the Lebedev Physical Institute [lecture notes]
 Spring 2014: Advanced graduate seminar, organised by Marcos Crichigno, on dualities and emergent gauge symmetry in condensed matter
 Fall 2012–Fall 2014: assisted Gleb Arutyunov in supervising MSc thesis in theoretical physics:
R Klabbers, Inozemtsev’s elliptic spin chains: asymptotic Bethe ansatz and thermodynamics (2014)
R J Rodger, A pedagogical introduction to the AGT conjecture (2013)  Fall 2013: Seminar on quantumintegrable models [mirror], organised together with André Henriques and Gleb Arutyunov [comparison of notations in our references]
 Spring 2013: Field theory in particle physics, taught by Bernard de Wit and Eric Laenen
During my master’s studies I assisted various Bachelor courses in physics and mathematics. I also taught at SSL in Leiden, preparing highschool students for their final exams in mathematics.
Last update: 18 May ’21