The REGAL project is happy to announce a workshop on the mathematical aspects of density-functional theory (DFT). The workshop will take place at Oslo Metropolitan University (OsloMet), campus Pilestredet, from the 20^th to the 24^th of April 2026.

Schedule

The schedule is preliminarily set to start at Monday the 20^th of April at noon and finish as Friday the 24^th of April at noon. A detailed program will be published her once the lineup of talks has been set.

Participants

The list of participants currently contains about 30 names, both local and international. A preliminary list of participants can be found here. The list will be periodically updated with new registrations.

Abstract

The workshop is devoted to the rigorous mathematical analysis and recent theoretical advances in density-functional theory (DFT), a cornerstone of computational quantum chemistry. While DFT has proven remarkably successful in practical applications, many of its core concepts remain mathematically underexplored. A central theme of the workshop will be the inverse Kohn–Sham problem — the task of reconstructing the effective non-interacting Kohn–Sham potential from a given electronic density. A central question is whether this inverse formulation offers a way to analyse the structure of the universal density functional and for evaluating the accuracy of approximate functionals. Despite its fundamental importance, the inverse problem is significantly less studied than the forward Kohn–Sham scheme and presents unique analytical and numerical challenges, including issues of existence, uniqueness, and stability of solutions. Additionally, the workshop will cover a range of other topics within the analysis of DFT, including foundational questions, extensions, functional approximation strategies, regularisation approaches, and numerical methods.

Topics

The final composition of the program will be shaped by the interests and expertise of the confirmed participants. Preliminary list of topics to be covered:

• The mathematical foundations of DFT
• Extensions of DFT such as quantum electrodynamical density-functional theory (QEDFT)
• Density-potential inversion, in particular Kohn–Sham inversion
• The Moreau–Yosida regularisation framework for DFT and its extensions
• Developments in time-dependent DFT (TDDFT)
• Novel strategies for developing and analysing functional approximations in DFT
• Numerical methods in DFT and their analysis, including convergence and error analyses.
• Other nearby topics in theoretical chemistry and materials science.

The workshop aims at bringing together researchers working on these and adjacent subjects in order to advance the applicability of DFT in both novel and established domains.

Venue

The workshop is tentatively scheduled at OsloMet’s Pilestredet campus, located in central Oslo. The venue is approximately a 10-minute walk from Nationaltheatret station, which provides convenient rail and metro connections, including direct trains to Oslo Airport Gardermoen (OSL). Both the Airport Express (Flytoget) and Vy regional trains (e.g., RE10, RE11, R12) offer frequent service to Nationaltheatret, with travel times of just under 30 minutes.

Contact

If you have any questions or if you are interested in participating, please feel free to contact the organisers.