From a small gathering to a multi-day international conference, the Inverse Days has evolved into one of the largest annually organised scientific meetings in Finland.
In 1995, a small group of inverse problems researchers gathered for a one-day workshop in Oulu, Finland. Just two years later, Finland’s inverse problems research community organised formally around the Finnish Inverse Problems Society, and the yearly workshop – later to be known as the Inverse Days – became the society’s official annual scientific meeting.
Since then, the Inverse Days has evolved from a small workshop into a multi-day international conference and highlight of the year for Finland’s inverse problems experts and students. In 2025, the Inverse Days gathered over 200 registered participants, making it one of largest annual academic conferences in Finland.
Scientific excellence in the heart of Helsinki
Hosted by the University of Helsinki on 15-17 December in its historical Main Building, this year’s conference included over 100 academic presentations both from experienced professionals and younger researchers with topics covering a wide range of inverse problems-related challenges, applications, and ambitions. The conference’s two plenary talks were presented by Assistant Professor in Numerical Analysis Tatiana Bubba (University of Ferrara, Italy) on tomographic imaging and Klarman Fellow Nicholas Nelsen (Cornell University, New York, U.S.) on introduction of machine learning field of operator learning to the field of inverse problems.
For years, Inverse Days events have included a dedicated Industry session in which professionals from different organisations have introduced real-world inverse problems faced in their respective fields. In 2025, this session included talks by Tuomo Kauranne, founder of the forestry-related intelligence provider Arbonaut, Antti Solonen, Senior Manager (Data Science) of energy-efficiency-focused engineering company Danfoss’ digital services, Çağlar Aytekin, Lead AI Developer of multiphysics simulation platform-provider Quanscient, Lauri Parkkonen, Senior Technology Advisor of neuroscience technology company MEGIN, and Mikko Lilja, Head of Software and Algorithm Development of medical imaging equipment manufacturer Planmed.
For the first time, this year’s conference also included a separate session focusing on Artificial Intelligence, organised by the Finnish Centre for Artificial Intelligence and FAME’s collaborative Special Interest Group AI for inverse problems and imaging. This session included talks by Associate Professor Andreas Hauptmann, a FAME Principal Investigator from the University of Oulu, Associate Professor Arto Klami, leader of the University of Helsinki’s Multi-source probabilistic inference research group, Dan Still, Partnerships Manager of CSC – IT Center for Science, and Tarmo Toikkanen, Senior Lead of Solutions at the Finnish Innovation Fund Sitra.
Warm encounters and bright futures
Outside of science-focused activities, the conference programme included an icebreaker event, the Young Researchers’ social event, the Women in Inverse Problems networking session, and conference dinner. All these activities – and especially the Young Researchers’ event with well over 100 participants – made it clear that the future of inverse problems research is in good and enthusiastic hands both in Finland and beyond.
As per yearly tradition, the Finnish Inverse Problems Society presented their Finnish Inverse Prize to recognise outstanding achievements in the field of inverse problems broadly defined, and to encourage future work in the field. The prize is most often awarded to a young researcher for an outstanding doctoral thesis on inverse problems. For 2025, this recognition was awarded to Postdoctoral Researcher Siiri Rautio for her doctoral research on solving imaging-related inverse problems with machine learning and traditional algorithms. Congratulations!
The Finnish Inverse Problems Society and FAME would like to thank all our wonderful speakers, conference participants, and organisers for making this event possible!
The Inverse Days conference will return in 2026 in Jyväskylä.
