Problem of the Week
Hilton Memorial Lecture
REFLECTIONS ON THE FORTY-YEAR CAREER OF A HUSBAND-AND-WIFE TEAM OF MATHEMATICIANS
Abstract. This speech was given on May 18, 2002 at the dinner banquet of the XXVI-th OSU-Denison Conference honoring Wolfgang Kappe on the occasion of his retirement.
“It's a wonderful life” was the title of a talk I gave a month ago at the MAA Seaway Section meeting. Its subtitle: reflections on the career of a mathematician. This time my subtitle is: Reflections on the forty-year career of a husband-and-wife team of mathematicians. Very appropriately so, since we are celebrating our fortieth wedding anniversary in two weeks!
In my last talk I reflected first on potential and actual role models before reflecting on my own career. Starting with Hypathia around 300 BC, it took me fifty minutes to go through the centuries. Don't worry, this time it can be done in fifteen minutes. There is just one role model who lived in the generation of my parents, a husband-and-wife team of research mathematicians who had each their own Ph.D. students and raised a family. I am talking of Bernhard and Hanna Neumann. Bernhard is still alive today, soon celebrating his ninety-third birthday. Hanna, born in 1914, died prematurely in 1971. Bernhard had to emigrate from Germany in 1933. Hanna followed him five years later to Great Britain. Their first years together were the turbulent times of World War II. For a long time they held academic jobs but in different cities, she in Hull, he in Manchester. In 1958 Hanna finally succeeded in joining Bernhard in Manchester. During that time they raised a family of five children. Finally, in 1963 they found jobs at the same university, the National University of Australia in Canberra.
Compared to the Neumann's, we were lucky. We had always our jobs at the same university and only had to pull up our stakes once going from Germany to the US, by the way, the same year the Neumann's moved to Australia. But let's start at the beginning:
“Once upon a time” Wolfgang and Liselotte met where all mathematicians meet, that mythical place Oberwolfach. By the end of 1959 we both had gravitated to the Black Forest area within a month of each other, Wolfgang as one of the mathematicians in residence in Oberwolfach while writing his dissertation with Reinhold Baer in Frankfurt, and me starting my dissertation with Theodor Schneider in Freiburg.
I heard about Wolfgang for the first time when Schneider mentioned that Kappe and Kegel, the two resident assistants in Oberwolfach, are named after two geometric objects, namely the cap of a sphere and the cone. Wolfgang heard about me for the first time from Erich Glock, my future brother-in-law and also a mathematician in residence in Oberwolfach. Once coming back from a visit in Freiburg, Erich reported that Theodor Schneider had brought along “ein Fraeulein Menger”. Wolfgang replied as any Berliner would have: ” Na und! (= so what!).
During my first year in Freiburg I came up to Oberwolfach a couple of times and we met on those occasions. In Spring 1961 I was appointed to the newly created position of a library assistant at Oberwolfach which I could take care of mainly from Freiburg. But on occasion I had to visit the institute for a few days at a time. Also, Theodor Schneider instructed me to help with the meetings while Wolfgang was preparing for his Ph.D. exam. The latter one did not quite work out as intended. In other words, we got to know each other during that time and my presence became a pleasant obstacle in Wolfgang's endeavor to prepare for the exam. After a few delays however, Wolfgang defended his dissertation in July 1961 and by that time we were already in agreement that we should get married once I finished my Ph.D. which happened in May 1962. We got married on June 1 of that year in Nuernberg.
Good that nature prevented us from reflecting on what marriage would do to our careers. It was the single biggest mistake we could make, in particular, if we wanted to stay in Germany. At that time each of us had good positions, Wolfgang as a postdoc in Frankfurt and me as an assistant in Freiburg. I could have kept it and commuted to Frankfurt. But we decided to live together. I moved to Frankfurt and became a “Hilfsassistent”.
Baer ran a tight ship in Frankfurt. International celebrities came through town and gave talks and he wanted everyone to be there. Others occasionally would miss such events and did not get noticed. If one or both of us were missing, Baer always noticed and told us so at the next opportunity, because he could not introduce us to the visitor as the husband-and-wife team and me in particular as “Frau Dr. Dr. Kappe”, one my own degree, the other my husband's, as is customary in Germany. A few years later in Oberwolfach, Baer scheduled talks back-to-back, first the Neumann's, then us.
Soon my husband's post doc would run out, and we started looking around for places to go. Opportunities came up, for one of us there, for the other somewhere else. We tried to stay optimistic, but Reinhold Baer knew better and gave us the advice to go to the US. He reasoned that the climate for a husband-and-wife team to succeed was better in the US. That was forty years ago and nothing has changed in Germany since then in this respect. Baer introduced us to Zassenhaus on the occasion of a visit to Oberwolfach. Zassenhaus just had moved from Notre Dame to Ohio State. We got our immigration visa just for the asking, got a plane ticket and landed in the US on September 16, 1963. Fresh off the plane, we started teaching a few days later. All of you who came here as graduate students at least had some idea how life would be as a college teacher. For us it was all new, it was a culture shock. It was sink or swim and we decided to swim. Thanks to the help of two people, Hans Zassenhaus who introduced us to academic life in the States, and Arno Cronheim, a long-time friend of Wolfgang, who introduced us to the daily life, we managed to swim. Above all it was very essential that we lived through this together and we were there for each other.
I could go on to report on the next 38 years of our marriage, but let me just conclude as in the fairy tale: ”… and they lived happily ever after”.