Celebratio Mathematica

Mary Ellen Rudin

A Tribute to Mary Ellen Rudin

by William Fleissner

Mary El­len Rud­in was an in­spir­a­tion to me and oth­er gradu­ate stu­dents. In­tel­lec­tu­ally, she was en­thu­si­ast­ic about set-the­or­et­ic to­po­logy. Emo­tion­ally, she was warm and kind not only to math­em­aticians but also to their spouses.

I re­mem­ber sem­inars on the ninth floor of Van Vleck Hall, with large win­dows over­look­ing Lake Men­d­ota and the city of Madis­on. Once she presen­ted the Reed–Zen­or proof that loc­ally com­pact, loc­ally con­nec­ted nor­mal Moore spaces are met­riz­able. She drew a Can­tor tree, put a unit in­ter­val at the top of each branch, sketched a red circle about the 0’s and a blue circle about the 1’s. It was not a proof of the the­or­em. It was more an ex­plan­a­tion why a counter­example can­not be con­struc­ted from Mar­tin’s Ax­iom. Even that was not rig­or­ously proved. But she con­veyed the ideas with great en­thu­si­asm. In the audi­ence, I thought, “I want to do math­em­at­ics like that!”

There were mem­or­able even­ings at their Frank Lloyd Wright-de­signed house on Ma­ri­nette Trail. (Oc­ca­sion­ally, tour­ists would look in the win­dows, and Wal­ter would stick out his tongue.) There would be food and drink in the kit­chen, and a circle of chairs in the liv­ing room, which was large in width and length and two stor­ies high. The win­ters in Wis­con­sin can be bit­terly cold, but then there would be a fire in the fire­place, mak­ing the gath­er­ing warm and cheery. The con­ver­sa­tion was var­ied, and every­one was wel­come to talk, not just the dis­tin­guished pro­fess­ors. The re­search group at Wis­con­sin felt like a big fam­ily.