The photo shows the Danish physicist Niels Bohr at a "bonzenfreie Kolloquium" 

organized for him by Lise Meitner (shown facing Bohr) in Dahlem near Berlin in 1920.

Bohr won the Nobel Prize in 1922 for his seminal contributions to the development of quantum mechanics. (And Meitner discovered nuclear fission in 1938 after fleeing to Copenhagen as a persecuted Jew.)

See CHARLES HARPER'S op-ed making the 70th anniversary of that discovery: )

Beyond his own genius, Bohr had a special talent as a catalyst in the development of genius in others, encouraging the development of great achievements in a large number of talented young people who came to live and work with him in Copenhagen in the 1920s and 1930s.

The hypercreative and fun environment that he and his wife Magrethe hosted in Copenhagen at the Institute for Theoretical Physics (founded in 1921), stands as an unparalleled example of astonishing breakthrough creativity in the history of physics at a particularly vital time when the perplexing nature and deep insights of quantum theory were pioneered. 

Gino Segre's wonderfully fascinating book, Faust in Copenhagen, tells the EXCITING story.

The German word "bonzenfreie" means without bigwigs. Meitner organized the meeting to host Bohr for a special day-long informal meeting with the younger chemists and physicists who were not (yet) professors. Academic protocol in those days  would have required the younger scientists to keep quiet in the presence of their hierarchical academic superiors.  Bohr had been invited to speak at a meeting with Einstein and other well-established professorial "bonzes."  Meitner and her young colleagues hoped to have an opportunity to share their questions and insights with Bohr.  The bonzenfreie Kolloquium was the solution.  

Bohr loved it.  And he recreated its dynamism the following year in Copenhagen when he opened his historic Institute.*


*For some details, see:  Lise Meitner (1964) "Looking Back" Bulletin of the Atomic Scientists, 20:11 ( November 1964), pp. 2-7. Section on page 7, "Bohr without bigwigs."

Available on-line via:, or directly:

See also page 70 of Gino Segre's absolutely wonderful book, Faust in Copenhagen for a description.

The photo is provided courtesy of the Niels Bohr Archive: J003.


 ---which identifies the people present in the photo):

Number: J003 

Category: Conferences 

Person(s): Stern, Otto; Lenz, Wilhelm; Franck, James; Ladenburg, Rudolf Walter; 

Knipping, Paul; Bohr, N.; Wagner, E.; Baeyer, Otto von; Hahn, Otto; 

Hevesy, George de; Meitner, Lise; Westphal, Wilhelm; 

Geiger, Hans Wilhelm; Hertz, Gustav Ludwig; Pringsheim, Peter 

Date: 1920 

Place: Berlin 

Occasion/Description: Das bonzenfreie Kolloquium 



Who is Niels Bohr?