# In Memoriam

We honor our colleagues who passed away in the past year: Grigory Barenblatt, Paul Chernoff, Jacob Feldman, Marina Ratner, Don Sarason, and Jack Silver.

### 2018

(Obituary by Alex Chorin)

Grigory Isaakovich was born in Moscow on July 10, 1927, and studied mathematics at Moscow University under the supervision of A.N. Kolmogorov and B.M. Levitan. He went on to become one of leading applied mathematicians world-wide, with extraordinary contributions to a wide variety of fields, including fluid mechanics, turbulence, flow in porous media, fracture, materials science, scaling, asymptotics and intermediate asymptotics. Despite the excellence of his work he faced many difficulties due to his Jewishness and also to his lack of enthusiasm for the regime. After the fall of communism, he could travel, and was appointed as the G.I. Taylor Professor of Fluid Mechanics at the University of Cambridge in the U.K. When he retired from that position he came to the United States, held a few short-term visiting positions, and then joined the Mathematics Department of the University of California, Berkeley, as a Professor in Residence, with a concurrent appointment at the Lawrence Berkeley Laboratory.

Professor Barenblatt held appointments as a foreign honorary member at the U.S. National Academy of Sciences, the U.S. National Academy of Engineering, the American Academy of Arts and Sciences, and the Royal Society of London, as well as a long list of other professional societies in multiple countries.

The long list of his awards includes the G.I. Taylor award from the US Society for Engineering Science, the Maxwell prize of the International Committee on Applied and Industrial Mathematics, the Lagrange Prize of the Accademia Nazionale dei Lincei, and the Timoshenko Award of the ASME.

### 2017

A memorial and celebration of life will be held 3-5 PM on April 4, 2017, at the U.C. Berkeley Faculty Club, for Paul Robert Chernoff, a member of our department for nearly five decades. He died January 17, 2017 at age 74, after a long illness. His research was in functional analysis, especially areas related to the mathematical foundations of quantum mechanics. He is recognized for the Chernoff Theorem, a result in functional analysis and Lie algebras which supports the Feynman path integral formulation of quantum mechanics, and for a lucid presentation of the Groenwald-van Hove "no go" theorem, relating classical mechanics to quantum mechanics.

Born in Philadelphia, Dr. Chernoff was the son of the late Drs. Benjamin and Edith Chernoff. He attended the Central High School of Philadelphia, and graduated summa cum laude from Harvard University. After earning his PhD at Harvard in 1968, he joined our department. He was a respected and popular teacher, who won multiple Distinguished Teaching Awards, and the Lili Fabilli and Eric Hoffer Essay Prize. He was a member of the Mathematical Associaton of America, and a fellow of the American Association for the Advancement of Science and of the American Mathematical Society.

He enjoyed cartooning and painting and was the author of numerous limericks. He is survived by brother Arthur Chernoff of Rydal PA and Arthur's wife Marcia, brother Donald Chernoff of Indianapolis IN and Donald's wife Ellen, and sister Ruth Sacks, née Aizen, of Yardley PA and Ruth's husband Milton, and by a nephew and three nieces.

Should friends desire, contributions in his memory may be donated to Mathematics at Berkeley, where they will be used to promote excellence in teaching and learning, or to a charity or cause of their choice.

(Obituary from the New York Times)

We very sadly report the passing of our colleague Professor Marina Ratner on July 7, 2017, at her home in El Cerrito, California. Professor Ratner was educated in Moscow, obtained her doctoral degree at the Moscow State University, emigrated to Israel in 1971, and joined the Berkeley Mathematics Department in 1975. Her work was mainly in ergodic theory and its connections with other parts of mathematics, and earned many honors, including the Ostrowski prize and the John J. Carty Award. She was a plenary speaker at the International Congress of Mathematicians and a member of the National Academy of Sciences. She was also an outstanding and beloved teacher and cared deeply about mathematics education.

She is survived by her daughter Anna Ratner, son-in-law Charles Cox, grandchildren Bryan and Maya, and nephews Michael Bialy (a Professor of Mathematics at Tel Aviv University) and Alex Bialy. The funeral will be held on Tuesday, July 18, at 11 am, at the Home of Eternity Cemetery, 5000 Piedmont Avenue, Oakland, and will be followed by a reception at Professor Ratner's home.

Passed away Saturday, April 8, 2017 at his home in Berkeley in the loving care of his family. He was 84 years of age. A native of Detroit, Michigan, and long-time resident of Berkeley, he is survived by his wife of 27 years, Mary Jennings of Berkeley; son Benjamin Sarason of Chicago, Illinois; step-daughters Anne Marie Jennings of Dripping Springs, Texas, and Allison Jennings of Berkeley; step-sons Herbert Jennings of Berkeley, and Daniel Jennings of Houston, Texas; sisters Constance Grossman of West Bloomfield, Michigan, and Judith Sarason of Kensington; brother Thomas Sarason of Medford, Oregon; and three step-grandchildren. A graduate of the University of Michigan, Ann Arbor, Mr. Sarason was a mathematics professor and researcher at the University of California Berkeley for over 50 years. As talented a mathematician and dedicated a teacher as he was, what those who knew him well regarded as most remarkable were his humility, kindness, gentleness and generosity. He retired in 2012.

Friends and acquaintances are cordially invited to attend memorial services Monday, April 17 at 2:00 p.m. in the Chapel of Sunset View Mortuary, top of Fairmount Avenue, El Cerrito. Memorial donations, if desired, may be made to the charity of the donor’s choice.

### 2016

(Obituary from the newsletter of the Group in Logic and the Methodology of Science)

It is with great sadness that we announce that Professor Jack Howard Silver died on Thursday, December 22, 2016. Professor Silver was born in 1942 in Missoula, Montana. After earning his A.B. at Montana State University (now the University of Montana) in 1961, he entered graduate school in mathematics at UC Berkeley. His thesis, completed in 1966, was supervised by Robert Vaught. In 1967 he joined the mathematics department at UC Berkeley where he also became a member of the Group in Logic and the Methodology of Science. He quickly rose through the ranks obtaining promotion to associate professor in 1970 and to full professor in 1975. From 1970 to 1972 he was an Alfred P. Sloan Research Fellow. Silver retired in 2010. At UC Berkeley he advised eighteen students, three of whom were in the Group in Logic (Burgess, Ignjatovich, Zach). His mathematical interests included set theory, model theory, and proof theory. His production was not extensive but his results were deep. A short summary of his results in set theory can be found here. Professor Silver was skeptical of the consistency of ZFC and even of third-order number theory. As Prof. Robert Solovay recently put it: “For at least the last 20 years, Jack was convinced that measurable cardinals (and indeed ZFC) was inconsistent. He strove mightily to prove this. If he had succeeded it would have been the theorem of the century (at least) in set theory.” He will be greatly missed.

### 2015

### 2014

We are very sad to report the sudden death of Professor Robert Coleman in the early morning on March 24, 2014, just a few months after his retirement and a few months short of his sixtieth birthday.

Professor Coleman was born in Glen Cove, New York in 1954. He received an A.B. from Harvard in 1976 and a Ph.D. from Princeton in 1979; he joined our department in 1983. His ground-breaking work in number theory, based primarily on his unique insight into p-adic geometry, transformed the field. He is especially known for his theory of p-adic integration (the “Coleman integral”) and his construction, with Barry Mazur, of the eigencurve, a richly complicated p-adic space which glues together families of modular forms and Galois representations. He is the author of 63 publications and had thirteen students and fifteen mathematical descendants. He was named a MacArthur Fellow in 1987.

Professor Coleman fought multiple sclerosis with great bravery for 29 years, never giving up his dedication to research in and teaching of mathematics, or his good humor and engagement with friends, colleagues, and the natural world.

### 2013

See memorial page by his student Oliver Knill at http://www.math.harvard.edu/~knill/history/lanford/

### 2012

We sadly report the death of our colleague Professor William G. Bade, who died on August 10, 2012, at the age of 88. Professor Bade received his PhD in 1951 at UCLA under Angus Taylor. He then spent three years at Yale, where he met Philip C. Curtis, Jr; the two became close friends and longtime mathematical collaborators.

Professor Bade joined the Berkeley faculty in 1955. He and Curtis were prominent contributors to the subject of Banach algebras, which was rapidly expanding at the time. Notably, they pioneered the study of radical Banach algebras, an infinite-dimensional generalization of rings of nilpotent matrices. Professor Bade directed 24 successful doctoral dissertations, and many of his students made significant advances in the field he and Curtis had originated.

Professor Bade served for many years as our Vice Chair for Graduate Affairs. His devotion to our graduate students went far beyond the call of duty. He viewed his role not merely as a mathematical advisor but also as a personal friend.

Professor Bade became Professor Emeritus upon his retirement in 1991. He is survived by his wife of 60 years, Elly, by six children, and by five grandchildren.

We were very sad to learn the death of our colleague Professor Shoshichi Kobayashi on August 29, 2012, at the age of 80. Professor Kobayashi joined our department faculty in 1962. He had done his undergraduate studies at the University of Tokyo, and obtained his PhD from the University of Washington, Seattle in 1956.

Professor Kobayashi was one of the most important contributors to the field of differential geometry in the second half of the twentieth century. His early work concerned the theory of connections; another major interest of his was the relation of curvature to topology, in particular on Kähler manifolds. The majority of his career, though, was devoted to complex geometry. Notions such as the Kobayashi pseudodistance and Kobayashi hyperbolicity have become indispensible tools for the study of mappings of complex manifolds.

Several of Professor Kobayashi's books are now standard references in differential and complex geometry, among them his two-volume treatise with Katsumi Nomizu entitled "Foundations of Differential Geometry" from which generations of students and other scholars have learned the essentials of the subject.

Professor Kobayashi served as Chair of the Department of Mathematics from 1978 to 1981, a time during which he stood up to the administration to preserve the department's space in Evans Hall. His legacy also includes the 35 PhD students whose dissertations he supervised at Berkeley.

### 2011

We are very saddened by the death of our colleague Professor William B. Arveson, on November 15, due to complications during surgery. Professor Arveson joined our department faculty in 1968. He had done his undergraduate studies at Cal Tech, and his graduate studies at UCLA. He soon came to be recognized as one of the world's leading research mathematicians studying algebras of operators on Hilbert spaces, and their applications, especially to quantum physics. Professor Arveson remained fully active in research up to the time of his death. Professor Arveson strongly inspired and influenced many other researchers. In particular, 29 doctoral students wrote their doctoral dissertations under his guidance.

### 2010

Emeritus Professor David Harold Blackwell passed away peacefully in Berkeley July 8, 2010. Professor Blackwell was born in Centralia, Illinois on April 24, 1919. Throughout his academic career he was a most distinguished teacher and researcher. He taught at Howard University for ten years before coming to Berkeley in 1955. At Berkeley he had appointments in both the Mathematics and Statistics departments. He became Emeritus Professor in 1989. Professor Blackwell will be missed by many communities. A memorial event will be held to honor and celebrate his life on Friday, October 15, 2010 at 4pm in the International House of UC Berkeley on 229 Piedmont Avenue, Berkeley, CA 94720.

See *A Tribute to Henry Helson* at http://www.ams.org/notices/201102/rtx110200274p.pdf

Emeritus Professor Gerhard Paul Hochschild passed away peacefully in Berkeley July 8, 2010. Professor Hochschild was born in Berlin on April 29. 1915. Throughout his academic career he was a most distinguished teacher and researcher. He was a visiting professor at Berkeley in 1955-56. He joined the department as Professor of Mathematics in 1958. He became Emeritus Professor in 1985. Professor Hochschild will be missed by many communities.

Professor Jerrold (Jerry) Marsden passed away peacefully in Pasadena, California, on September 21, 2010. Professor Marsden was born in Ocean Falls, British Columbia, Canada on August 17, 1942. Throughout his academic career he was a most distinguished teacher and researcher. He joined the faculty at UC Berkeley in 1968 and was member of the faculty until his official retirement from UC Berkeley in 1997. He joined the faculty at Caltech in 1995. More information about him is available at: http://media.caltech.edu/press_releases/13385