Snapshot from life

Max Planck is considered one of the most influential scientists of the 20th century. A project team from physics and regional history wants to explore other sides to this honorary citizen of Kiel using personal documents.

Collection of old letters and photos
© Julia Siekmann, Kiel University

From Max Planck's original letters to correspondence with famous physics colleagues to the family's holiday postcards – the 20 boxes and folders contain a lot of work and many treasures for professors Oliver Auge (Regional History, left) and Michael Bonitz (Theoretical Physics) and their team.

"I'm glad we were able to get it in the elevator," said Michael Bonitz, Professor of Theoretical Physics, pointing to the large safe that has been standing in the Physics Centre for a few months now. In it are stacks of boxes with documents, some up to 130 years old, and related to Max Planck, who was born in Kiel in 1858. At the time, one of his professors warned him against pursuing a career in physics – everything there was to research in the field had already been researched anyway. "It's a good job Planck didn't listen to him. His quantum theory later revolutionised physics and earned him the Nobel Prize in 1919."

Planck remained closely linked to his home town of Kiel throughout his life, even after science had seen him move on to Berlin. Michael Bonitz set up a first exhibition on his life and work in Kiel in the Physics Library, and two of Planck's great-granddaughters attended the opening. When the family later contacted Bonitz again after a household dissolution, he immediately agreed to borrow Planck's personal documents for review. "But it was such a huge quantity, unsorted and in the old handwriting as well, that I soon realised we would need support." Oliver Auge, Professor of Regional History at Kiel University, had already had a lot of dealings with biographies of Kiel professors in connection with the Kieler Gelehrtenverzeichnis (Kiel Directory of Scholars), and gladly agreed to help. "I think this kind of cooperation between disciplines that you wouldn't necessarily immediately think were related is absolutely brilliant. I'd love to see more of it."

Manuscripts, personal letters, family photos and much more

The Max Planck Foundation made it possible to digitise the original documents for the first time and to purchase the safe for their proper storage. Coordinated by Karoline Liebler, research associate at the Kieler Gelehrtenverzeichnis, a number of research assistants from the regional history and physics departments have been working since the beginning of the year on sifting through, sorting and digitising the more than 20 boxes and folders. They are being financed by the Collegium Philosophicum, a research network of the Faculty of Arts and Humanities, and the University Board of Kiel University.

One aim of the project is to make the documents available for research. “As historians, we're not 'hunters and gatherers'. We have to select what is historically relevant and sensitise students to it," emphasised Professor Auge. There is plenty to sort through, from manuscripts and letters to photos, passports and holiday postcards. There are a number of letters by Planck himself, as well as personal correspondence with equally famous colleagues such as Wernher von Braun, Werner Heisenberg and Planck's pupil Lise Meitner. “This is a vivid snapshot of Planck's scientific achievements, but also of his personally battered life," said Auge. His first wife and all four of their children died during his lifetime. "Even the way Planck acted as a scientist in the Second World War in the face of a totalitarian regime is given a new topicality by the Russian war of aggression, and needs to be considered in a differentiated and balanced way."

Evaluation to be integrated into teaching

The documents are to be further evaluated in a project seminar during the winter semester. "It's great for our students to be able to work with originals and share their results with the public," said Auge. It is not unlikely that there could be a book, an exhibition or a digital presentation. Some pieces will be integrated into the existing collection in the Physics Library. Bonitz had already digitally processed parts of the collection together with the Muthesius University of Fine Arts and Design in Kiel during the COVID lockdown. The first part of the digital presentation is due to be completed shortly with the support of the Max Planck Foundation.

Insights into the project will be given at a theme evening on 4 October, the 75th anniversary of Planck's death. Lectures and discussions will focus on the role that Planck plays for Kiel and in current physics – right up to the development of state-of-the-art quantum computers. And naturally, "old treasures" from the safe will also be on display.

Author: Julia Siekmann