Juris Hartmanis, first CS department chair, dies at 94

Juris Hartmanis, a Turing Award-successful pioneer who was instrumental in setting up pc science as an impartial industry, and founding chair of Cornell’s Department of Personal computer Science, died July 29 at 94.

Frequently identified as “the father of computational complexity,” Hartmanis found out a set of essential laws that govern the issue of computation, laying the basis for a detailed principle of the performance and limits of computing.

At Cornell, Hartmanis designed just one of the 1st laptop or computer science departments in the earth.

“Juris was a visionary researcher, chief and mentor,” explained Kavita Bala, dean of the Cornell Ann S. Bowers Higher education of Computing and Info Science. “His legacy lives on in the discipline he aided construct and in the minds of the many individuals, like me, he influenced.”

Hartmanis was born in Riga, Latvia, in 1928. His father, a standard in the Latvian army, died in jail right after the Soviet occupation of Latvia in the 1940s, main Hartmanis and his spouse and children to emigrate to Germany. He done higher college in a displaced people camp and attained an undergraduate diploma in physics from the College of Marburg. By way of the sponsorship of a family mate, he moved to the U.S. and acquired his master’s degree in mathematics at the College of Kansas Town (now regarded as the University of Missouri–Kansas City) in 1951 and his Ph.D. in mathematics from the California Institute of Technology in 1955.

From 1955 to 1957 he was an teacher in arithmetic at Cornell, adopted by 9 months as an assistant professor of mathematics at Ohio Condition University. In 1958 he was tempted by industrial investigate and joined Typical Electric (GE) Analysis Laboratory in Schenectady, New York, where he invested the upcoming seven yrs.

It was at GE that he and colleague Richard Stearns founded the industry of computational complexity, an area of investigation that remains a person of the central topics in laptop or computer science to this day. There had been earlier get the job done in investigation of algorithms that tried to build higher or reduced time bounds on precise algorithms for numerous computational issues, but pretty couple of typical rules that unified the habits of these algorithms.

Their key contribution was to review the inherent complexity of the difficulties themselves. In their 1965 paper, “On the Computational Complexity of Algorithms,” they described the essential notion of a complexity class – a course of issues that are solvable in a certain time bound on a multitape Turing equipment. They showed that this notion is particularly strong in the perception that complexity classes are independent of time scale and impervious to small modifications of the machine product, consequently the outcomes were being suitable to any fair product of computation. They proved quite a few theorems with regards to separation and containment of complexity classes, thus creating the existence of an infinite hierarchy of complexity classes.

For this foundational perform, Hartmanis and Stearns received the 1993 Turing Award, the leading honor in personal computer science.

In 1965, Hartmanis returned to Cornell as the first chair of the recently started Division of Laptop Science. Beneath his leadership, graduates went on to come to be school members at new personal computer science departments forming all in excess of the state.

“Juris has been an inspiration to generations of computer system scientists since the early days of the subject,” reported Dexter Kozen, the Joseph Newton Pew Jr. Professor in Engineering in the Office of Computer Science. “I am fortunate to have researched underneath Juris at Cornell, exactly where his influence on the society of the section is nonetheless felt to this day. The news of his passing has left me with a profound sense of reduction, as I’m confident is true with several.”

Hartmanis served as chair of the department 3 periods – 1965-71, 1977-83 and 1992-93 – and finally retired from the college in 2001 as the Walter R. Go through Professor of Laptop or computer Science and Engineering, Emeritus.

“We have so considerably to thank Juris for,” mentioned Éva Tardos, the Jacob Gould Schurman Professor of Personal computer Science and chair of the Department of Computer Science. “He established our section, and established the collegial and collaborative lifestyle that has been encouraging us be a wonderful section to this working day.”

Beyond his assistance to Cornell, Hartmanis contributed to countrywide initiatives to advance the subject of laptop science. He chaired a Nationwide Research Council Examine that yielded the 1992 publication, “Computing the Future: A Broader Agenda for Personal computer Science and Engineering.” The report laid out a research agenda and advisable a framework of education and learning, funding and management intended to convey computing into the 21st century.

From 1996 to 1998, Hartmanis served as the assistant director of the Nationwide Science Basis, where he led the Directorate of Pc and Details Science and Engineering (CISE). There, he steered the endeavours to change the educational research network NSFnet into the early internet.

He also served on the science board and science steering committee of the Santa Fe Institute, an unbiased, nonprofit study group established to progress investigate in complexity science.

Among the his a lot of awards, Hartmanis was a member of the American Academy of Arts and Sciences, the Nationwide Academy of Engineering, the Countrywide Academy of Sciences and the Latvian Academy of Sciences, and a fellow of the Association for Computing Equipment and the American Mathematical Modern society. He gained the Bolzano Gold Medal from the Academy of Sciences in the Czech Republic and the Computing Analysis Association’s Distinguished Provider Award. In 1993, he was the receiver of a Humboldt Foundation Senior U.S. Scientist Award, and he held honorary doctorates from the University of Missouri and the College of Dortmund.

Juris was predeceased by his spouse Elly (Rehwaldt) and is survived by three children: Reneta McCarthy, Martin Hartmanis and Audrey Langkammerer.

The family requests that in lieu of flowers, donations can be sent to the Ithaca Sciencenter in his memory. A Celebration of Lifetime will take spot at the Ithaca Yacht Club on Aug. 15, noon-2 p.m.

Patricia Waldron is a author for the Cornell Ann S. Bowers College or university of Computing and Data Science.