Ellis Cumberbatch

Advocate and Architect of CGU’s Math Programs

The Claremont Graduate University (CGU) and Institute of Mathematical Sciences (IMS) communities mourn the death of emeritus Professor Ellis Cumberbatch, who passed away in September at the age of 87.

Cumberbatch had been an instrumental figure in the development and expansion of math programs at CGU and in The Claremont Colleges. Provost Patricia Easton informed the CGU community of his passing in an email message that called him “a pillar of CGU Mathematics” since his arrival in Claremont in 1981.

Easton’s message to the CGU community also acknowledged Cumberbatch’s humor, saying that “Ellis’s dry wit will remain with us always.” Her message closed with the words of poet Mary Elizabeth Frye: “Do not stand at my grave and weep. I am not there; I do not sleep.”

Cumberbatch earned his PhD in Applied Mathematics at the University of Manchester in 1958. His dissertation foretold the design of an ocean-going ship hull that would allow it to travel in excess of 230 miles per hour. His mathematical contributions and research interests ranged from differential equations and fluid mechanics to semiconductors and industrial modeling.

Cumberbatch arrived in Claremont in 1981, after holding positions at the California Institute of Technology, the Courant Institute of Mathematical Sciences, Leeds University, and Purdue University.

Ellis was responsible for so much of our deeply collaborative approach at IMS and in the broader Claremont math community. What he valued above all else was that we all work together and we all get along.” — Allon Percus

For his IMS colleague Allon Percus, Cumberbatch’s efforts to build a close-knit mathematics community in Claremont were just as important as the work he contributed as a researcher and scholar.

“Ellis was responsible for so much of our deeply collaborative approach at IMS and in the broader Claremont math community,” Percus explained. “What he valued above all else was that we all work together and we all get along.”

With colleague Jerry Spanier, Cumberbatch revitalized the IMS, and his vision and foresight were instrumental in establishing the Financial Engineering program (jointly with the Drucker School of Management), the PhD in Engineering and Computational Mathematics (jointly with CSULB), and the Claremont Center for the Mathematical Sciences.

During his tenure at CGU, he served in numerous capacities, including as dean, department chair, and director of the Claremont Mathematics Clinic.

Through sustained efforts over many years of clinic projects, Cumberbatch and his students made important contributions to understanding and modeling transistors, even anticipating quantum effects that are becoming important as their sizes are reduced.

Cumberbatch’s efforts to foster a collegial, close-knit math community extended beyond the campus to the entire Claremont Colleges. He was the co-founder, with Bob Borrelli at Harvey Mudd College, of a unique organization that draws on the talent and resources of Claremont’s six independent math programs, the Claremont Center for the Mathematical Sciences (CCMS).

Cumberbatch continued to be an active member of the IMS faculty well into his retirement, in 2009, including a one-year appointment as dean in 2011-12.

Cumberbatch is survived by his long-term partner, Suzanna Stafford, and children from his first marriage, Guy, Louis, and Evelyn Cumberbatch; his daughter Ellen is deceased. He is also survived by grandchildren including Guy’s children, Adam and Christopher Cumberbatch, and Evelyn’s children, Boaz and Lily Kaffman. Suzanna’s daughter, Jeni Hess Brage, and Jeni’s two children, Shelby and Cassidy Brage, were also close to him. Ellis is also survived by his sister, Pamela Dagger, of Blackpool, England.


The family requests no flowers, but if people wish to donate to the charity of their choice in Ellis’s memory, that would be warmly appreciated.

Cards of sympathy and condolence may be sent to:
The Cumberbatch Family
644 West 10th Street
Claremont Ca 91711