# In Memoriam:

Efraim Armendariz and Ted Odell

## Efraim Armendariz

Efraim P. Armendariz passed away on February 13th, 2013, surrounded by family. He touched many people during his lifetime and leaves behind a wonderful legacy. Efraim served as a faculty member at UT Austin from fall 1966 where he was a respected academic and a warm colleague amongst his fellow mathematicians.

Outside UT, Efraim was many things - a devoted family man, a coach and role model to several little league baseball teams, an avid music-lover and guitar music performer, and a friend to many. His love of music intersected with his academic life, as over the years Efraim and other department members provided the core of the rock band Ax Nelson.

Efraim was a specialist in noncommutative ring theory, a basic area of twentieth-century algebra. Frequently, he and his collaborators would adopt the point of view that commutative rings and finite-dimensional algebras were more amenable to analysis, and then they tried to understand to what extent general noncommutative rings could be understood based on these more tractable cases. This led Efraim to study so-called P.I. rings, which, it was hoped, behaved like commutative rings. Efraim was particularly known for studying P.I. rings that satisfied von Neumann regularity and similar properties. Here, Efraim and his coauthors proved striking results detailing how precisely worded statements could be generalized from the commutative case. In another direction, Efraim noticed that so-called reduced rings had an interesting property connected to polynomials and rings with this property came to be called Armendariz rings. Various authors studied and are continuing to study Armendariz rings and related concepts.

Over the years, Efraim had an important influence on teaching at UT Austin. Besides being a dedicated teacher, he was an active supporter of the UTeach program, he was a member of the Mathematical Association of America's ad hoc committee on a national center for the teaching of undergraduates, and he was instrumental in bringing to UT Austin the Emerging Scholars Program initiated at the University of California at Berkeley by Uri Treisman who later joined the Department of Mathematics here at UT.

In 1984, he became the Associate Chairman of the Department of Mathematics and served for seven years in that capacity. In 1991, he became chairman of the department. At the end of his four-year term as chairman, members of the department asked him to serve for another term, and he agreed. This happened two more times, so that in the end he served as chairman for a remarkable sixteen years. His constant reappointment shows the respect in which he was held by his colleagues and the quality of the work he was doing. And his willingness to serve this long shows the strength of his commitment to the department and the University of Texas. During his chairmanship, the department dramatically improved its national standing so that by the end of his tenure, the department was ranked fourteenth among all United States mathematics departments and fourth among mathematics departments at public universities in the United States.

If you would like to make a gift in Efraim Armendariz’s memory, please click HERE.

## Ted Odell

Ted Odell passed away on January 9th, 2013. Ted arrived at The University of Texas at Austin in 1977 and spent the next thirty-six years as a member of the Department of Mathematics. Over the course of his time here, Ted had significant impact on the research and instructional missions of the department as well as being called up to serve in many administrative roles. One unintended consequence of the large administrative load was that it helped his research! As Ted put it, the more administrative work he did, the more he enjoyed his research.

Ted's excellent mathematical research made him a leader in his field from soon after earning his Ph.D. until his untimely death. He also had a superb talent for explaining deep theories and arguments using easy and convincing approaches, often using simple pictures. The combination of his international research stature and his excellence at exposition meant that he frequently received invitations to give lectures and lecture series around the world. For example, he presented series of lectures in Spain, Great Britain, and China, and he was an invited speaker at the International Congress of Mathematicians in Zürich in 1994.

His Ph.D. thesis contained results that led to two important papers, one with W. Johnson (his advisor), and the other with Haskell Rosenthal (who was a faculty member at UT).

Ted's thesis work was merely the beginning of a long and productive research career. He was a very highly regarded member of the Banach space community. He authored nearly a hundred research articles, including many that represented major breakthroughs in the subject, and he was an expert in combinatorial and set theoretic methods in analysis. Among his many results, the solution of the Distortion Problem of Hilbert space, which he obtained with Thomas Schlumprecht in 1992, was one of the highlights of his contributions in this area.

Ted's technical accomplishments in research mathematics were only part of his contributions to the field. His manner of conducting himself in his position of being a research leader illustrates his kindness and character, well beyond mathematics. He cared for people; he took care in dealing with people, and he knew when it was important to take care. When new people appeared at a conference, he made sure that they were welcomed and included. He would invite them to come to lunch and dinner. He was one of the few so called "Big Shots" of the area with whom people, especially young people, felt comfortable talking. Everyone could ask him questions without being afraid to look stupid. Even when he was not the organizer of a conference, he was one of the main focal points to which people converged. It is difficult for researchers in the Banach space community to imagine future meetings without Ted there.

At UT, he would take care of new faculty, help them settle in, help them learn the ropes, and help them figure out what is important and what is not. Many post-doctoral fellows remember his help and kindness with great affection. He helped newcomers with everything from their teaching to their research to their retirement accounts. He was unfailingly kind and thoughtful.

Ted was a teacher dedicated to his students, and over time he became convinced that students would be well-served to have some inquiry-based learning experience during their education. He taught some of his own classes that way, and he helped the Inquiry-Based Learning project enormously by developing materials, mentoring graduate students and faculty, and co-directing the inquiry-based learning project.

His absence continues to be strongly felt in the department, at the University, and in the research community.