Manuel Blum
http:///www.cs.cmu.edu/~mblum
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Manuel Blum
, the Bruce Nelson Professor of Computer Science at Carnegie Mellon University,
is a pioneer in the field of theoretical computer science and the winner of the 1995 Turing Award
in recognition of his contributions to the foundations of computational complexity theory and its
applications to cryptography and program checking, a mathematical approach to writing programs
that checks their work.
He was born in Caracas, Venezuela, where his parents settled after fleeing Europe in the 1930s,
and came to the United States in the mid-1950s to study at the Massachusetts Institute of
Technology. While studying electrical engineering, he pursued his desire to understand thinking
and brains by working in the neurophysiology laboratory of Warren S. McCulloch and Walter
Pitts, then concentrated on mathematical logic and recursion theory for the insight it gave him on
brains and thinking. He did his doctoral work under the supervision of artificial intelligence
pioneer Marvin Minsky and earned a Ph.D. in mathematics in 1964.
Dr. Blum began his teaching career at MIT as an assistant professor of mathematics and, in 1968,
joined the faculty of the University of California at Berkeley as a tenured associate professor of
electrical engineering and computer science. He was Associate Chair for Computer Science,
1977-1980 and in 1995 was named the Arthur J. Chick Professor of Computer Science. Dr. Blum
accepted his present position at Carnegie Mellon in 2001.
The problems he has tackled in his long career include, among others, methods for measuring the
intrinsic complexity of problems. Blum’s Speedup theorem is an important proposition about the
complexity of computable functions. The Blum axioms give a machine-independent way to
understand the complexity of computation, whether that computation is done by a human or a
computer. Since his early work on the intrinsic limitations of computing devices, Blum’s research
has focused on the single unifying theme of finding positive, practical consequences of living in a
world where computational resources are bounded. In his work, Blum has shown that secure
business transactions, pseudo-random number generation, program checking, and more recently,
CAPTCHAs for detecting bot intruders, are possible in part because all computational devices are
resource bounded.
Blum’s current research includes the HumanOID (Human Oriented ID) project, a cryptographic
project designed to develop a challenge-response authentication protocol that humans can perform
entirely in their heads. For this, people must be able to authenticate themselves to a system while
a powerful machine-based adversary that knows the protocol listens on the line and records every
challenge and response. The system would have to be incapable of learning to impersonate that
human.
Manuel Blum
http:///www.cs.cmu.edu/~mblum
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A member of the National Academy of Sciences and the National Academy of Engineering, he is
a fellow of the American Academy of Arts and Sciences, the American
Association for the
Advancement of Science, and the Institute of Electrical and Electronics Engineers. Dr. Blum has
held a Sloan Foundation Fellowship and received a University of California at Berkeley
Distinguished Teaching Award, their Faculty Research Award, the Sigma Xi’s Monie A. Ferst
Award, the Carnegie Mellon Herbert A, Simons Teaching Award, among other honors. He is the
author of more than fifty papers published in leading scientific journals and has supervised the
theses of thirty-five doctoral students, who now pepper almost every major computer science
department in the country. The many ground-breaking areas of theoretical computer science
chartered by his academic descendants are legend.