The editors of the journal Optimization want to inform, with deep sadness, our community about the death of our former Associate Editor, Professor Rolf Klötzler, who passed away on 15 November 2021.
We have lost a famous scientist and engaged university teacher, a creative researcher who had inspired students and colleagues by his lectures like he had been inspired during his life by his academic teachers Ernst Hölder and Herbert Beckert.
With his research topics, Prof. Klötzler bended a great arc from the problems of Hilbert to problems in geometry and corresponding problems in practice.
In addition to his many publications (let us refer to his developed duality theory which is based essentially on field theory of calculus of variations and to his given foundations for the computation of optimal solutions of one-dimensional and multi-dimensional control problems), Prof. Klötzler collaborated on the creation of the two volumes of the ‘Mathematical Dictionary’ which is based on Teubner’s preliminary work from around 1930. Later he also worked on the new edition of Caratheodory’s ‘Calculus of Variations and Partial Differential Equations of the First Order’ from 1935 which was operated by Ernst Hölder.
Thanks to him that the University of Leipzig had very fruitful scientific co-operations with Vietnam, and for this engagement, Prof. Klötzler got the medal of the friendship of Vietnam.
His name is well-known in the mathematical community. Prof. Klötzler was chairman of the former Mathematical Society of the GDR and an elected member of the National Academy of Sciences ‘Leopoldina’.
Thanks to his administrative experience; he organized and carried out the annual autumn schools at the Baltic Sea, which had a formative influence on young scientists but also on senior researchers.
Prof. Klötzler has served the mathematical field admirably as editor and co-editor of numerous mathematical journals. From 1968 until his retirement, he was an active member of the editorial board of our journal Optimization. The special issue – Volume 38, Number 4 (1996) – is devoted to him.
We will never forget his interesting ideas, results and wonderful co-operation.
We will always keep Professor Rolf Klötzler in honorable memory.