(updated 2024-01-24)

I am a Professor in the Numerical Analysis group of the University of Oxford, and a Tutorial Fellow at Oriel College, Oxford.

I work on the numerical solution of partial differential equations, with a particular focus on

- finite element methods,
- bifurcation analysis of nonlinear PDE,
- adjoint techniques, their application and automation,
- preconditioners and fast solvers.

I have applied the numerical techniques I develop to various applications, in the areas of renewable energy, cardiac electrophysiology, glaciology, magnetohydrodynamics, quantum mechanics, and liquid crystals.

I lead the development of dolfin-adjoint and defcon, and regularly commit to PETSc, petsc4py, and firedrake.

2025-02-24: I will give a invited talk at the 3rd SFB International Workshop on Taming Complexity in Partial Differential Systems organised by Anton Arnold, Norbert Mauser, Ilaria Perugia, Dirk Praetorius, and Joachim Schöberl in Vienna, Austria.

2024-11-28: I will give a talk in the Cambridge Applied and Computational Mathematics seminar series, hosted by Matt Colbrook.

2024-11-28: I will give a talk in the Edinburgh Applied and Compuational Mathematics seminar series, hosted by Kaibo Hu.

2024-09-23: I will give a plenary talk at a conference on Modelling, partial differential equations analysis and computational mathematics in material sciences in Prague, Czechia.

2024-09-16: I am organising the Firedrake 2024 user meeting in Oxford, UK.

2024-07-01: I will attend the PDESoft 2024 conference in Cambridge, UK.

2024-06-21: I will attend the European Finite Element Fair organised by Erik Burman and others in London, UK.

2024-06-10: I will give a plenary talk at the New Trends in Numerical Analysis of PDEs conference organised by Clément Cancès, Claire Chainais, Maxime Herda, Simon Lemaire, and Antoine Zurek in Lille, France.

2024-06-10: Kars Knook will organise a minisymposium on Preconditioners for High Frequency Helmholtz Problems at the Preconditioning 2024 meeting in Atlanta, USA.

2024-05-20: I will give a plenary talk at the HPCSE 2024 High Performance Computing in Science and Engineering conference in Soláň, Czechia.

2024-05-03: I gave a talk in the Warwick Mathematics Colloquium.

2024-04-03: I gave a plenary talk at the Exploiting Algebraic and Geometric Structure in Time-Integration Methods workshop organised by Santolo Leveque, Stefano Massei, Cecilia Pagliantini, Luca Saluzzi, and Milo Viviani in Pisa, Italy. Boris Andrews also gave a presentation.

2024-03-11: I attended the PDEs and Geometry: Numerical Aspects workshop at ICERM, as part of the Numerical PDEs: Analysis, Algorithms, and Data Challenges semester program.

2024-03-06: I spoke at the annual UKAEA NEPTUNE workshop.

2024-02-29: I hosted Stefano Zampini for a talk in the Computational Mathematics and Applications seminar.

2024-02-05: I taught a graduate school on using Firedrake to solve PDEs at ICERM, as part of the Numerical PDEs: Analysis, Algorithms, and Data Challenges semester program. Update: the slides and code for the course are available.

2024-01-30: Welcome to Diego Hayashi Alonso, who is visiting for a year from the Universidade de São Paulo.

2024-01-25: I hosted Fleurianne Bertrand for a talk in the Computational Mathematics and Applications seminar.

2024-01-22: I gave a seminar jointly in the Optimisation and Numerical Analysis / Applied Mathematics series at the University of Birmingham.

2024-01-15: Pablo Brubeck spoke in a minisymposium at WONAPDE 2024 in Concepción, Chile.

2024-01-03: A new paper on multiple solutions of the Grad-Shafranov equations has been accepted in Nuclear Fusion Letters.

2023-12-23: A new paper is up on arXiv about the kinetic derivation of a compressible Leslie-Ericksen equation for rarified calamitic gases, with Umberto Zerbinati and Giovanni Russo.

2023-12-06: I gave a seminar in the Mathematical Modelling series at Charles University Prague.

2023-11-20: I hosted a research visit from Brendan Keith.

2023-10-12: Congratulations to Francis Aznaran on winning a Society of Science Fellowship at the University of Notre Dame!

2022-10-02: Welcome to Kars Knook and Mingdong He, who both start their DPhil studies today!

2023-09-05: Congratulations to Gonzalo Gonzalez de Diego on passing his DPhil viva! Thanks to Dan Goldberg and Peter Howell for serving as examiners.

2023-08-31: I gave a plenary talk at the annual meeting of the Irish Mathematical Society.

2023-08-20: I spoke in the Scalable Solvers for Multiphysics Problems minisymposium at ICIAM, organised by Alexander Heinlein and Matthias Mayr.

2023-08-20: Boris Andrews, Aaron Baier-Reinio, Pablo Brubeck, Duygu Sap, and Umberto Zerbinati spoke at ICIAM in Tokyo, Japan.

2023-08-14: A new paper is up on arXiv about a full approximation scheme multilevel method for variational inequalities, with Ed Bueler. Update: accepted in SISC.

2023-08-14: Pablo Brubeck spoke at the ICOSAHOM conference in Seoul, South Korea.

2023-08-14: I organised a conference on Numerical Analysis in the 21st Century, in honour of the retirement from Oxford of Nick Trefethen.

2023-08-01: I have joined the editorial board of the Numerical Mathematics and Scientific Computation book series, published by Oxford University Press.

2023-07-09: Umberto Zerbinati spoke at the NGSolve User Meeting in Portland, Oregon.

2023-07-04: Duygu Sap spoke at a workshop on Structure-preserving numerical methods for partial differential equations in Lausanne, Switzerland.

2023-06-27: Aaron Baier-Reinio, Pablo Brubeck, and Umberto Zerbinati spoke at the Strathclyde Numerical Analysis conference in Glasgow, Scotland.

2023-06-14: Umberto Zerbinati, India Marsden, and Aaron Baier-Reinio spoke at the FEniCS 2023 conference in Cagliari, Italy.

2023-05-29: I gave a short course on numerical bifurcation analysis at the EMS summer school on mathematical modelling, numerical analysis and scientific computing in Kácov, Czechia. The slides are available here.

2023-05-27: A new paper is up on arXiv about discrete breathers in Klein-Gordon lattices. Update: accepted in Chaos.

2023-05-12: Umberto Zerbinati gave a talk at the European Finite Element Fair.

2023-05-19: Congratulations to Matteo Croci and Ioannis Papadopoulos on being shortlisted for the 2023 IMA Leslie Fox Prize!

2023-04-21: I attended the SIAM UKIE section annual meeting in Trinity College Dublin. Aaron Baier-Reinio, India Marsden, and Umberto Zerbinati gave talks.

2023-04-18: I attended a PRISM Hackathon at Missenden Abbey.

2023-04-17: Welcome to Maryam Parvizi, who is a long-term visitor from Leibniz University Hannover on a Humboldt Fellowship.

2023-03-28: I gave two talks at the Memorial University of Newfoundland, hosted by Scott MacLachlan, and generously supported by an Atlantic Association for Research in the Mathematical Sciences Distinguished Lectureship.

2023-03-04: A new paper is up on arXiv about smectic structures in button-like confinements.

2023-03-01: Pablo Brubeck gave a talk in the Exterior Calculus in Numerical Computing, Modeling, and Simulation minisymposium at SIAM CSE23, organised by Ari Stern, James Fairbanks, Ingeborg Gjerde, and Kaibo Hu.

2023-03-01: I organised a minisymposium (part one, part two) at SIAM CSE23 on Modeling and Computation for Implicitly Constituted Materials: Fluids, Solids, Plasmas, and Mixtures, alongside Josef Málek. Aaron Baier-Reinio gave a talk in the session.

2023-02-28: I gave a talk in the Advances in Large-Scale Solvers in Computational Science and Engineering minisymposium at SIAM CSE23, organised by Eric de Sturler and Chen Greif.

2023-02-27: Gonzalo Gonzalez de Diego gave a talk in the Reliable and Efficient Methods for Coupled Problems in Porous Media minisymposium at SIAM CSE23, organised by Fleur Bertrand and Jakub Both.

2023-02-16: I hosted Olga Mula for a talk in the Computational Mathematics and Applications seminar.

2023-02-15: Congratulations to Pablo Brubeck on passing his DPhil viva! Thanks to Paul Fischer and Kaibo Hu for serving as examiners.

2023-02-14: I gave an invited talk at the Mathematics and microscopic theory for random soft matter systems workshop organised by René Wittmann, Hartmut Löwen and Matthias Sperl.

2023-02-09: I hosted Ed Bueler for a talk in the Computational Mathematics and Applications seminar.

2023-02-05: Duygu Sap has submitted a manuscript on discrete tensor product Bernstein-Gelfand-Gelfand sequences, with Francesca Bonizzoni, Kaibo Hu, and Guido Kanschat.

2023-01-26: Umberto Zerbinati gave a talk on nematoacoustics at the 22nd GAMM Seminar on Microstructures in Vienna, Austria.

2023-01-23: Welcome to Duygu Sap, who starts as a postdoc with me, funded on the PRISM project.

2023-01-18: I hosted Misha Kilmer for a talk in the Computational Mathematics and Applications seminar.

2023-01-04: I gave a talk in the Firedrake meeting, as did Umberto Zerbinati, India Marsden, and Francis Aznaran.

2022-12-13: I served on the PhD jury of Michal Outrata, a student of Martin Gander, at the University of Geneva.

2022-12-06: I gave a talk in the KAUST Mathematics and Applications Colloquium, hosted by Jinchao Xu.

2022-12-05: I gave a talk in the KAUST Computer Science Graduate Seminar, hosted by David Keyes.

2022-11-25: A new paper is up on arXiv about solvers for the Riesz maps of the de Rham complex with optimal complexity in polynomial degree, with Pablo Brubeck. These allow us to solve certain canonical problems with very high polynomial degree (up to *p=31*) on unstructured meshes in 3D. Update: accepted in SISC.

2022-11-24: A new paper is up on arXiv about how to enforce electroneutrality in Onsager-Stefan-Maxwell models with charged species, with Alexander Van-Brunt and Charles Monroe. Update: accepted with no modifications in Electrochimica Acta.

2022-11-10: A new paper is up on arXiv about two conjectures on the Stokes complex in three dimensions on Freudenthal meshes, with Ridgway Scott and Lawrence Mitchell. Update: accepted in SISC.

2022-11-07: Gonzalo Gonzalez de Diego gave a talk in the Mathematics on Ice seminar series, on "A numerical exploration of glacier sliding with cavitation".

2022-11-07: I gave a talk in the Tufts Applied Mathematics seminar, hosted by Misha Kilmer and James Adler.

2022-11-04: I gave a talk in the Courant Computational Mathematics and Scientific Computing seminar, hosted by Georg Stadler and Benjamin Peherstorfer.

2022-10-27: Congratulations to Nicolas Boullé on his commendation by the Divisional Board of Examiners for his excellent thesis.

2022-10-21: Francis Aznaran gave a talk in the Applied Mathematics seminar in Warwick.

2022-10-19: Pablo Brubeck spoke in the Imperial-UCL Numerics Seminar.

2022-10-07: Congratulations to Alexander Van-Brunt on passing his DPhil viva! Thanks to John Newman and Endre Süli for serving as examiners.

2022-10-03: Welcome to Aaron Baier-Reinio, India Marsden, and Umberto Zerbinati, who each start their DPhil studies today!

2022-10-02: I organised a workshop on Defects and Distortions of Layered Complex Fluids (22w5159) at the Banff International Research Station, Canada, alongside Scott MacLachlan, Tim Atherton, Emmanuelle Lacaze and Francesca Serra.

2022-09-28: Congratulations to Francis Aznaran on passing his DPhil viva! Thanks to Colin Cotter and Kathryn Gillow for serving as examiners.

2022-09-20: Congratulations to Fabian Laakmann on passing his DPhil viva! Thanks to John Shadid and Andy Wathen for serving as examiners.

2022-09-15: Welcome to Àlex Ferrer, who is visiting me in Oxford for a year, funded by Universitat Politècnica de Catalunya and the Catalan government.</a>

2022-09-05: I attended a workshop about the development of the UKAEA NEPTUNE edge plasma simulator, part of the ExCALIBUR programme.

2022-08-30: Congratulations to Nicolas Boullé on passing his DPhil viva! Thanks to Andrew Stuart and Jared Tanner for serving as examiners.

2022-08-25: A new paper is up on arXiv about finite element methods for multicomponent flows, with Francis Aznaran, Alexander Van-Brunt, and Charles Monroe. We develop discretisations for a PDE system coupling the Onsager-Stefan-Maxwell equations with a compressible Stokes equation; the combination describes the flows of mixtures in a common thermodynamic phase. Update: accepted in IMAJNA.

2022-08-17: Good news! I have been promoted to full professor.

2022-08-16: I gave a contributed talk at the 9th International Symposium on Bifurcations and Instabilities in Fluid Dynamics in Groningen, the Netherlands.

2022-08-12: A new paper is up on arXiv about complex, stable solutions of the 3D two-component Gross-Pitaevskii equations, with Nicolas Boullé, Isaac Newell and Panos Kevrekidis.

2022-07-28: I gave a talk at the SciCADE International Conference on Scientific Computation and Differential Equations in Reykjavik, Iceland, in the minisymposium MS32 Structure-preserving numerical methods for plasma models organised by Cecilia Pagliantini and Kaibo Hu.

2022-07-27: A new paper is up on arXiv about finite element discretisations of the smectic density equation, with Abdalaziz Hamdan and Scott MacLachlan. Update: accepted in JCP.

2022-07-11: I gave an invited presentation (Numerical Analysis and Applications section) at the Equadiff 15 conference in Brno, Czechia.

2022-06-26: I gave a talk at the 30 years of Acta Numerica conference at the Banach Centre in Będlewo, Poland.

2022-06-20: I gave a plenary talk at the 24th Conference of the International Linear Algebra Society in Galway, Ireland.

2022-06-15: I gave a departmental seminar in the Aeronautics Department of Imperial College London. A recording is available online.

2022-06-10: Congratulations to Gonzalo Gonzalez de Diego on winning best student presentation in the International Glaciological Society meeting in Bilbao!

2022-06-06: I gave a keynote talk at the minisymposium organised by Peter Ohm, John Shadid and Matthias Mayr at the ECCOMAS Congress in Oslo, Norway.

2022-05-05: Congratulations to Nicolas Boullé on winning an INI-Simons Postdoctoral Fellowship in Mathematics!

2022-04-24: I am the acting head of the Oxford Numerical Analysis group during Nick Trefethen's sabbatical, until 2022-09-30.

2022-04-11: I gave a talk at the workshop on Recent Advances in Numerical Linear Algebra for PDEs, Optimization, and Data Assimilation at the ICMS in Edinburgh, organised by John Pearson and Jemima Tabeart.

2022-03-30: I hosted Apala Majumdar, Yucen Han, and Sophie McLaughlan for a research visit, funded by a Heilbronn Small Grant.

2022-02-24: A new paper is up on arXiv about structure-preserving and helicity-conserving finite element approximations and preconditioning for the Hall MHD equations, with Fabian Laakmann and Kaibo Hu. Update: accepted in Journal of Computational Physics.

2022-02-18: Congratulations to Pablo Brubeck on winning the Student Paper Competition of the 2022 Copper Mountain Conference on Iterative Methods! Congratulations to the other winners also.

2022-02-16: A new paper is up on arXiv about preconditioners for computing multiple solutions of topology optimisation problems, with Ioannis Papadopoulos. Update: accepted in SISC.

2022-02-15: A new paper is up on arXiv about monolithic multigrid for implicit Runge-Kutta discretizations of incompressible fluid flow and MHD problems, with Razan Abu-Labdeh and Scott MacLachlan.

2022-01-27: A new paper is up on arXiv about the optimal control of Hopf bifurcations, with Nicolas Boullé and Marie Rognes. Update: accepted in SISC.

2022-01-01: I have joined the SISC Editorial Board as an Associate Editor.

2022-01-01: I have joined the Committee on Applications and Interdisciplinary Relations of the European Mathematical Society.

2021-11-11: A new paper is up on arXiv about the numerical solution of viscous contact problems applied to glacial sliding, with Gonzalo Gonzalez de Diego and Ian Hewitt. Update: accepted in JFM.

2021-10-27: A new paper is up on arXiv about transformations for Mardal-Tai-Winther and Arnold-Winther elements, with Francis Aznaran and Rob Kirby. Update: accepted in SMAI JCM.

2021-10-13: A new paper is up on arXiv about variational and numerical analysis of a Q-tensor model for smectic-A liquid crystals, with Jingmin Xia. Update: accepted in M2AN.

2021-10-11: Welcome to Boris Andrews, who began his DPhil studies today! He is co-supervised by Wayne Arter of the Culham Centre for Fusion Energy.

2021-09-28: I gave a talk in the Topology Optimization Webinar.

2021-09-24: Congratulations to Ioannis Papadopoulos on passing his DPhil viva! Thanks to Anton Evgrafov and Kathryn Gillow for serving as examiners.

2021-09-17: Congratulations to Fabian Laakmann on winning a best presentation prize at Firedrake '21!

2021-09-15: A new paper is up on arXiv about accounting for thermodiffusion in the Onsager-Stefan-Maxwell equations, with Alexander Van-Brunt and Charles Monroe. Update: accepted in AIChE Journal.

2021-08-03: A new paper is up on arXiv about the analysis of semicoercive Stokes variational inequalities arising in glaciology, with Gonzalo Gonzalez de Diego and Ian Hewitt. Update: accepted in SINUM.

2021-08-02: A new paper is up on arXiv about fast and *p*-robust solvers for very high-order FEM discretisations using the fast diagonalisation method, with Pablo Brubeck. Update: accepted in SISC.

2021-07-19: I attended the Conference on Numerical Analysis and Acoustics in Devon, England. It was incredible to see research talks and socialise in person again! Thanks to Sheehan Olver and Anastasia Kisil for organising it.

2021-07-06: Congratulations to Jingmin Xia on winning a permanent position at the National University of Defense Technology in Changsha!

2021-07-05: I gave a talk in the Berlin Oberseminar on Optimization, Control and Inverse Problems, organised by Michael Hintermüller.

2021-07-02: I was awarded a Whitehead Prize by the London Mathematical Society.

2021-06-28: Welcome to Isaac Newell, a 3rd year student at Oriel, who'll be working with me for the summer on an LMS Undergraduate Research Bursary.

2021-06-28: Welcome to Geoffrey Gachemi, a tutorial fellow at the Technical University of Kenya, who'll be working with me for the summer on a Mfano Africa mentorship.

2021-06-23: I gave a talk at a minisymposium organised by Johann Rudi, Omar Ghattas, Lukas Holbach, and Georg Stadler at the SIAM Conference on Mathematical & Computational Issues in the Geosciences.

2021-06-13: I attended a workshop on Novel Mathematical Methods in Material Science: Applications to Biomaterials, held online at the Banff International Research Station.

2021-06-09: I gave a talk at the XXth International Workshop on Numerical Methods for non-Newtonian Flows, held online at the Casa Matemática Oaxaca.

2021-06-01: Congratulations to Jingmin Xia on passing her DPhil viva! Thanks to Carme Calderer and Endre Süli for serving as examiners.

2021-06-01: A new paper is up on arXiv about controlling bifurcation structures with shape optimisation, with Nicolas Boullé and Alberto Paganini. Update: accepted in SISC.

2021-05-19: Congratulations to Nicolas Boullé on being shortlisted for the 2021 IMA Leslie Fox Prize!

2021-05-19: I gave an IWR colloquium in Heidelberg, organised by Rob Scheichl.

2021-05-18: A new paper is up on arXiv about three-field formulations for H^2-elliptic problems, with Scott MacLachlan and Abdalaziz Hamdan. Update: accepted in Computers and Mathematics with Applications.

2021-05-17: I gave a talk at a minisymposium at the SIAM Conference on Mathematical Aspects of Materials Science, organised by Shawn Walker and Carme Calderer.

2021-05-16: A new paper is up on arXiv about changing discretisation to suit different HPC architectures, with Jack Betteridge and David Ham. Update: accepted in IEEE Computing in Science and Engineering.

2021-05-03: I am organising a BIRS workshop (21w5164) on Efficient Simulation Algorithms for Viscoelastic and Viscous non-Newtonian Fluids in Banff, Canada. Update: cancelled due to the pandemic.

2021-04-30: A new paper is up on arXiv about augmented Lagrangian preconditioners for magnetohydrodynamics, with Fabian Laakmann and Lawrence Mitchell. Update: accepted in SISC.

2021-04-22: Congratulations to Florian Wechsung for winning a Mathematical Institute DPhil Thesis Prize!

2021-04-19: Congratulations to Nicolas Boullé on winning a £5000 G-Research DPhil prize!

2021-04-07: I was awarded the 2020 **Charles Broyden Prize** for the best paper published in Optimization Methods and Software in 2020, with Matteo Croci and Thomas Surowiec.

2021-03-29: Pablo Brubeck, Pablo Alexei Gazca Orozco, Abdalaziz Hamdan, and Razan Abu-Labdeh gave talks at the 20th Copper Mountain Conference on Multigrid Methods.

2021-03-26: Pablo Brubeck, Ioannis Papadopoulos, Francis Aznaran, Rob Kirby, and Pablo Alexei Gazca Orozco gave talks at the FEniCS 2021 conference.

2021-03-12: I gave a seminar in the Numerical Analysis and Scientific Computing seminar series at the Courant Institute.

2021-02-21: A new paper is up on arXiv about multiple solutions in Rayleigh-Bénard convection, with Nicolas Boullé and Vassilios Dallas. Update: accepted in Physical Review E.

2021-02-15: A new paper is up on arXiv about analysis of ferronematic liquid crystals in one dimension, with Apala Majumdar, James Dalby, and Jingmin Xia. Update: accepted in SIAP.

2021-02-05: A new paper is up on arXiv about discretising the Mori model of electrodiffusion and water movement in brain tissue, with Ada Ellingsrud, Marie Rognes, and Nicolas Boullé. Update: accepted in Mathematical Medicine and Biology.

2021-02-02: A new paper is up on arXiv about a new model and discretisation for smectic-A liquid crystals, with Jingmin Xia, Tim Atherton, and Scott MacLachlan. Here's a video of a double screw dislocation arising in a simulation of a focal conic domain. The video shows the zero isosurfaces of the density variation, which are coloured by height to aid depth perception. Update: nominated as an editor's suggestion in Physical Review Letters.

2021-01-21: I gave a talk in the new Irish Numerical Analysis Forum.

2021-01-14: I am attending the online UKAEA ExCALIBUR-NEPTUNE kickoff meeting to design a new code to simulate the turbulent edge of a plasma in a tokamak reactor.

2020-11-24: I am organising a workshop on Planning for exasale continuum mechanics software, with Jack Betteridge and David Ham. This is part of our ExCALIBUR working group.

2020-11-17: A new paper is up on arXiv about multigrid methods for phase field modelling of multivariant martensitic formation, with Karel Tůma, Mohsen Rezaee-Hajidehi, Jaroslav Hron, and Stanislaw Stupkiewicz. Update: accepted in CMAME. Here's a video of the microstructure evolution in a pseudoelastic CuAlNi single crystal during nano-indentation.

2020-11-15: The HKIAS International Conference on Mathematical Analysis and its Applications has been rescheduled. Update: deferred (again) due to the coronavirus pandemic.

2020-11-06: A new paper is up on arXiv about discretisations and solvers for anisothermal implicitly-constituted non-Newtonian flows, with Alexei Gazca and Endre Süli. Update: accepted in Mathematics of Computation.

2020-10-19: Congratulations to Alexei Gazca for passing his DPhil viva! Thanks to Maxim Olshanskii and José Carrillo for serving as examiners.

2020-09-30: I have been invited to give a talk in the 2nd PRISM workshop on applications beyond CFD.

2020-09-25: Congratulations to Hamza Alawiye for passing his DPhil viva! Thanks to Yibin Fu and Derek Moulton for serving as examiners.

2020-09-22: I have been invited to give a talk in the partial differential equations describing far-from-equilibrium open systems conference organised by Miroslav Bulíček.

2020-09-21: I served as PhD opponent for the thesis of Tomáš Gergelits on operator preconditiong at Charles University Prague. Congratulations, Tomáš!

2020-07-15: I am hosting a research visit from Emilio Silva of the University of São Paulo. Update: deferred due to the coronavirus pandemic.

2020-07-01: I have been invited to give a seminar at the IWR in Heidelberg by Rob Scheichl. Update: deferred due to the coronavirus pandemic.

2020-07-01: A paper has been accepted about the bifurcation analysis of model problems relating to kidney stone removal with Jess Williams, Sarah Waters, Simon Tavener, Derek Moulton, Ben Turney, and Alfonso Castrejón-Pita in the Journal of Fluid Mechanics.

2020-06-29: A new paper is up on arXiv about automating implicit (fully coupled) Runge-Kutta timestepping methods, with Rob Kirby and Jorge Marchena Menendez. Update: accepted in ACM Transactions on Mathematical Software.

2020-06-26: A new paper is up on arXiv about monolithic multigrid methods for magnetohydrodynamics, with James Adler, Tom Benson, Eric Cyr, Scott MacLachlan and Ray Tuminaro. Update: accepted in SIAM Journal on Scientific Computing.

2020-06-22: I am giving a talk at a minisymposium organised by Scott MacLachlan and Niall Madden at the International Linear Algebra Society meeting in Galway, Ireland. Update: deferred due to the coronavirus pandemic.

2020-06-18: I am hosting Colin Cotter of Imperial College London for a (update: now online) seminar in the Computational Mathematics and Applications series.

2020-06-09: I am hosting a research visit from Mark Adams of Lawrence Berkeley Laboratory. Update: deferred due to the coronavirus pandemic.

2020-06-05: I am hosting Weinan E for a colloquium at the Mathematical Institute. Update: deferred due to the coronavirus pandemic.

2020-06-05: A new paper is up on arXiv about stable discretisations for the Onsager-Stefan-Maxwell diffusion problem, with Alexander Van-Brunt and Charles Monroe. Update: accepted in IMAJNA.

2020-05-28: I am giving an online talk in the Computational Mathematics and Applications series.

2020-05-28: I have been invited to give a seminar at WIAS in Berlin by Michael Hintermüller. Update: deferred due to the coronavirus pandemic.

2020-05-25: I will give a mini lecture course at the EMS summer school on mathematical modelling, numerical analysis and scientific computing in Kácov, Czechia. Update: deferred due to the coronavirus pandemic.

2020-05-18: I have been invited to give a lecture at the ICMS online workshop on Novel modelling insights into confined soft matter systems.

2020-05-06: A new paper is up on arXiv about augmented Lagrangian preconditioners for implicitly-constituted non-Newtonian flows, with Alexei Gazca. Update: now accepted in SISC.

2020-04-24: A new paper is up on arXiv about computing multiple solutions of topology optimisation problems, with Ioannis Papadopoulos and Thomas Surowiec. Update: accepted in SISC.

2020-04-24: I am hosting a research visit from Catherine Mavriplis of the University of Ottawa. Update: deferred due to the coronavirus pandemic.

2020-04-22: A new paper is up on arXiv about multiple solutions of Bose-Einstein condensates in three dimensions, with Panos Kevrekidis, Stathis Charalampidis and Nicolas Boullé. Update: accepted in Physical Review A.

2020-04-21: I will give a mini lecture course to the EU Regional School in Inverse Problems at RWTH Aachen University on adjoint methods. Update: deferred due to the coronavirus pandemic.

2020-04-20: A new paper is up on arXiv about Reynolds-robust solvers for the incompressible Navier-Stokes with the Scott-Vogelius discretisation on macroelements, with Ridgway Scott, Lawrence Mitchell and Florian Wechsung. Update: accepted in SMAI Journal of Computational Mathematics.

2020-04-15: A new paper is up on arXiv about augmented Lagrangian preconditioners for the Oseen-Frank model in liquid crystals, with Florian Wechsung and Jingmin Xia. Update: accepted in BIT Numerical Mathematics.

2020-04-01: Welcome to Jack Betteridge, who is starting a postdoc at Imperial College London, supervised by David Ham and myself. Jack is funded on EPSRC grant EP/V001493/1.

2019-03-12: I am hosting Mark Girolami of the University of Cambridge for a seminar in the Computational Mathematics and Applications series.

2020-02-20: I am hosting Marie Rognes of Simula Research Laboratory for a seminar in the Industrial and Applied Mathematics series.

2020-02-06: A new paper is up on arXiv about robust solvers for linear elasticity with the Scott-Vogelius discretisation on macroelements, with Ridgway Scott, Lawrence Mitchell and Florian Wechsung. Update: accepted in IMAJNA.

2020-02-05: I am attending the UKAEA Fusion Modelling System workshop in Birmingham.

2020-01-24: I am hosting Panos Kevrekidis for a colloquium at the Mathematical Institute.

2020-01-20: Congratulations to Matteo Croci for passing his DPhil viva! Thanks to Rob Scheichl and Endre Süli for serving as examiners.

2020-01-16: I am hosting a research visit from Thomas Surowiec of Philipps-Universität Marburg.

2020-01-09: I am hosting a research visit from Tim Atherton of Tufts University.

2020-01-08: I am hosting a research visit from Mariano Beguerisse of Spotify.

2019-12-18: A new paper is up on arXiv about PCPATCH, a preconditioner in PETSc for the topological construction of relaxation methods, with Matt Knepley, Lawrence Mitchell and Florian Wechsung. Update: accepted in ACM TOMS.

2019-12-09: I have been invited to give a lecture at the ICERM workshop on Numerical Methods and New Perspectives for Extended Liquid Crystalline Systems organised by Apala Majumdar, Shawn Walker and Jan Lagerwall.

2019-11-29: A new paper is up on arXiv about the bifurcation analysis of two-component Bose-Einstein condensates, with Panos Kevrekidis, Stathis Charalampidis and Nicolas Boullé. Update: now published in CNSNS.

2019-11-28: I served as PhD examiner for Jack Betteridge. Congratulations!

2019-11-27: A new paper is up on arXiv about multilevel quasi Monte Carlo methods, with Matteo Croci and Mike Giles. Update: accepted in SISC.

2019-11-26: A new paper is up on arXiv about complexity bounds for supermesh construction, with Matteo Croci. Update: now published in JCP.

2019-11-21: I have been invited to give a lecture at the HKIAS International Conference on Mathematical Analysis and its Applications by Philippe Ciarlet and John Ball. Update: sadly this conference has been deferred until next year due to the closure of the university.

2019-11-15: I am hosting Doug Arnold for a colloquium at the Mathematical Institute.

2019-11-13: I served as DPhil examiner for Thomas Roy. Congratulations!

2019-11-04: I am hosting a research visit from Simon Tavener of Colorado State University.

2019-10-28: I am visiting the Geometry, compatibility and structure preservation in computational differential equations programme at the Isaac Newton Institute in Cambridge. I will talk on the 31st.

2019-10-25: I am giving a talk in the Bath Numerical Analysis Seminar.

2019-10-23: I am giving a talk in the Imperial-UCL Numerics Seminar.

2019-10-18: I am hosting Reidun Twarock for a colloquium at the Mathematical Institute.

2019-10-01: Welcome to Gonzalo Gonzalez de Diego, Nicolas Boullé, Alexander Van-Brunt, Fabian Laakmann, and Francis Aznaran, who all start their DPhils with me today! Gonzalo is co-supervised by Ian Hewitt, Alexander by Charles Monroe, and Francis by Endre Süli.

2019-09-26: I am hosting a research visit from Ridgway Scott of the University of Chicago.

2019-09-23: Congratulations to Florian Wechsung for passing his DPhil viva! My first student to graduate. Thanks to Roland Herzog and Andy Wathen for serving as examiners.

2019-09-04: I am hosting Aretha Teckentrup of the University of Edinburgh for the viva of Zhenru Wang.

2019-09-01: Welcome to Panos Kevrekidis, who is visiting myself and Heather Harrington on sabbatical for a year! His sabbatical is generously supported by a Visiting Professorship award from the Leverhulme Trust.

2019-08-26: A new paper is up on arXiv about local Fourier analysis of additive Vanka schemes for the Stokes equations, with Yunhui He and Scott MacLachlan. Update: now published in NLAA.

2019-08-08: I have been awarded a Departmental Teaching Award by the Mathematical Institute for my lecture course C6.4 Finite Element Methods for PDEs.

2019-07-29: I am visiting Scott MacLachlan of Memorial University of Newfoundland for a month. This visit is generously funded by an LMS Scheme 4 grant.

2019-07-09: I am visiting Anton Schiela at the University of Bayreuth.

2019-07-01: I am giving a plenary talk at the Preconditioning conference in Minneapolis, Minnesota.

2019-06-10: I am visiting Josef Málek of Charles University Prague.

2019-06-07: I am hosting Michael Hintermüller for a colloquium at the Mathematical Institute.

2019-05-22: I am giving a talk at the Bath-Oxford-Strathclyde meeting on liquid crystals.

2019-04-30: A new paper is up on arXiv about deflation for semismooth equations and variational inequalities, with Matteo Croci and Thomas Surowiec. Update: now published in OMS.

2019-04-29: I am visiting Chris Rycroft and Katia Bertoldi of Harvard University.

2019-04-19: A new paper is up on arXiv about three-field finite element discretisations for implicitly-constituted non-Newtonian flows, with Alexei Gazca and Endre Süli. Update: now published in SINUM.

2019-04-02: I am giving a talk at the LMS Mathematics in Life Sciences conference in Oxford.

2019-03-24: I am giving a talk at the 19th Copper Mountain Conference on Multigrid Methods in Colorado.

2019-03-07: I am hosting Lawrence Mitchell of Durham University for a seminar in the Computational Mathematics and Applications series.

2019-01-11: I am attending the SIAM UKIE meeting in Oxford.

2018-12-05: I am hosting Maxim Olshanskii of the University of Houston for the viva of Niall Bootland. Update: Niall passed. Congratulations!

2018-11-13: I am hosting a research visit from Lawrence Mitchell of Durham University.

2018-11-02: I am hosting Jon Keating for a colloquium at the Mathematical Institute.

2018-11-01: I am hosting James Maddison of the University of Edinburgh for a seminar in the Computational Mathematics and Applications series.

2018-10-15: I am visiting Saullo Castro at TU Delft.

2018-10-01: I am hosting a research visit from Scott MacLachlan of Memorial University of Newfoundland.

2018-10-01: Welcome to Jingmin Xia and Ioannis Papadopoulos, who begin their DPhil studies today! Ioannis is co-supervised by Endre Süli.

2018-09-17: I am hosting a research visit from Thomas Surowiec of Philipps-Universität Marburg.

2018-08-30: I am giving another lecture course to the group of Emilio Silva, this time on adjoints.

2018-08-09: A new paper is up on arXiv about Reynolds-robust preconditioners for the incompressible Navier-Stokes, with Lawrence Mitchell and Florian Wechsung. Update: now published in SISC.

2018-07-09: I am attending the SIAM annual meeting in Portland, Oregon.

2018-06-18: I am giving a summer (winter?) school on finite elements to the group of Emilio Silva at the Escola Politécnica of the University of São Paulo.

2018-06-15: I am hosting Alfio Quarteroni for a colloquium at the Mathematical Institute.

2018-05-28: I am visiting Ridgway Scott at the University of Chicago centre in Paris.

2018-04-26: I am giving a seminar in MOX, Dipartimento di Matematica, Politecnico di Milano.

2018-04-10: I am teaching a summer (spring?) school on sensitivity and optimisation in Tuscany, with Matthew Juniper and Peter Schmid.

2018-03-21: I am hosting the 2018 FEniCS conference in Oxford.

2018-01-22: Congratulations to Florian Wechsung on winning first place in the G-Research DPhil prize!

2017-11-26: A new paper has been accepted on glaciological inverse problems in Pine Island Glacier, Antarctica, with Teresa Kyrke-Smith and Hilmar Gudmundsson.

2017-10-01: Welcome to Hamza Alawiye and Alexei Gazca, who begin their DPhil studies today! My co-supervisors are Alain Goriely (Hamza) and Endre Süli (Alexei).

2017-07-18: I am giving an invited seminar at the annual meeting of the Canadian Applied and Industrial Mathematics society in Halifax, Nova Scotia.

2017-06-26: I am teaching a summer school on finite elements and FEniCS at the University of Chicago, with Ridgway Scott.

2017-06-14: A new paper is up on arXiv about the bifurcation analysis of cholesteric liquid crystals, with David Emerson, James Adler, Scott MacLachlan and Timothy Atherton.

2017-06-13: A new paper is up on arXiv about higher-order PDE-constrained shape optimisation, with Alberto Paganini and Florian Wechsung.

2017-05-26: I am giving an invited seminar at the SIAM UKIE National Student Chapter Conference in Galway, Ireland.

2017-05-25: A new paper has been accepted on the bifurcation analysis of Bose-Einstein condensates, with Stathis Charalampidis and Panos Kevrekidis.

2017-04-10: I am teaching a guest lecture course PMR5412 Modelling and Numerical Simulation via Variational Calculus at the Escola Politécnica of the University of São Paulo, hosted by Emilio Silva and the Research Centre for Gas Innovation.

2017-03-20: I am spending a few weeks at the Institute for Pure and Applied Mathematics at UCLA, as part of the Computational Issues in Oil Field Applications programme.

2017-01-30: A new paper has been accepted on multiscale modelling of liquid crystal devices, with Martin Robinson, Apala Majumdar, Chong Luo and Radek Erban.

2017-01-20: I have been appointed as an editorial board member of SIAM’s Fundamentals of Algorithms book series.

2017-01-16: I am teaching C6.4 Finite Element Methods for PDEs this term. My introductory lecture notes on finite elements may be of interest. Any comments gratefully received!

2017-01-02: A new paper is up on arXiv about recovering inundation profiles from tidal data, with Simon Funke and Matthew Piggott.

2016-10-01: I am delighted to announce that I have been appointed as an Associate Professor in the Mathematical Institute and as a Tutorial Fellow at Oriel College.

2016-10-01: Welcome to Florian Wechsung, and Matteo Croci, who begin their DPhil studies today under my supervision! My co-supervisors are Mark Taylor of London Computational Solutions (Florian), and Marie Rognes of Simula Research Laboratory and Mike Giles (Matteo).

2016-09-28: A new paper is up on arXiv about the analysis of Carrier’s problem with Jon Chapman.

2016-08-01: Welcome to Alberto Paganini, who has begun a postdoctoral appointment with me! He comes from a PhD at ETH Zurich with Ralf Hiptmair. He will work with me on shape optimisation problems.

2016-06-21: A new paper is up on the arXiv about geometric Markov chain Monte Carlo methods for infinite-dimensional inverse problems with Alex Beskos, Shiwei Lan, Mark Girolami and Andrew Stuart.

2016-06-20: I’m teaching at a summer school on Solving PDEs with FEniCS with Ridgway Scott at the University of Chicago.

2016-06-10: I’m teaching at a summer school on Frontiers in PDE-constrained Optimization at the IMA in Minnesota.

2016-05-08: James Maddison and I have released libsupermesh, a fast implementation of an algorithm for supermesh construction.

2016-03-16: A new paper is up on arXiv about optimal preconditioners for the Ohta–Kawasaki equations with John Pearson.

2016-03-15: There’s an open faculty position in numerical analysis in Oxford (an associate professorship). Apply by April 29!

2016-01-28: A new paper is up on arXiv about using deflation to compute multiple equilibria of nematic liquid crystals with James Adler, David Emerson and Scott MacLachlan.

2015-11-30: Another paper is up on arXiv about linear and nonlinear solvers in variational fracture mechanics with Corrado Maurini. The code that supports the manuscript is available on bitbucket.

2015-09-19: Images from the SIAM Awards Lunch in Beijing are online.

2015-09-18: I gave the invited scientific lecture to the annual general meeting of NAG.

2015-09-01: A new paper is up on arXiv about PDE-constrained optimisation, deflation and Schur complement preconditioners.

2015-08-31: I’ve just released a Python implementation of Mike Giles’ multilevel Monte Carlo demo code.

2015-08-27: The first deflation paper has been published online in SISC.

2015-08-13: I collected the Wilkinson prize at ICIAM 2015 in Beijing today. Thanks again to NAG, ANL and NPL.

2015-07-16: I have been selected for polar service with the British Antarctic Survey! I will be undertaking fieldwork in the Antarctic this November as part of an observational campaign on the retreating ice sheets on the east coast of the Antarctic peninsula, on Flask Glacier and Scar Inlet.

2015-06-23: I came second in the Fox prize competition, joining company such as Andy Wathen, Peter Sweby, Alan Edelman, Mark Ainsworth, Barry Smith, and Des Higham. Congratulations to Iain Smears and Alex Townsend.

2015-06-11: I have won **the 2015 Wilkinson prize for Numerical Software**, along with my colleagues Simon Funke, David Ham and Marie Rognes.

2015-03-06: I have been shortlisted for the **17th IMA Leslie Fox prize in numerical analysis**.