Perhaps you are thinking of the 1927 Solvay Conference? https://en.wikipedia.org/wiki/File:Solvay_conference_1927.jpg https://en.wikipedia.org/wiki/File:Solvay_

Perhaps you are thinking of the 1927 Solvay Conference? https://en.wikipedia.org/wiki/File:Solvay_conference_1927.jpg https://en.wikipedia.org/wiki/File:Solvay_conference_1927.jp...