Title: Turing's Computable Real Numbers and Why They Are Still Important Today

Speaker: Edmund M. Clarke

Time: 10:00, Friday, 19th April, 2013

Venue: #334, 3rd Floor, Building #5, Institute of Software, Chinese Academy of Sciences

Abstract:

Although every undergraduate in computer science learns about Turing Machines, it is not well known that they were originally proposed as a means of characterizing computable real numbers. For a long time, formal verification paid little attention to computational applications that involve the manipulation of continuous quantities, even though such applications are ubiquitous. In recent years, however, there has been great interest in safety-critical hybrid systems involving both discrete and continuous behaviors, including autonomous automotive and aerospace applications, medical devices of various sorts, control programs for electric power plants, and so on. As a result, the formal analysis of numerical computation can no longer be ignored. In this talk, we focus on one of the most successful verification techniques, temporal logic model checking. Current industrial model checkers do not scale to handle realistic hybrid systems. We believe that the key to handling more complex systems is to make better use of the theory of the computable reals, and computable analysis more generally. We argue that new formal methods for hybrid systems should combine existing discrete methods in model checking with new algorithms based on computable analysis. In particular we discuss a model checker we are currently developing along these lines.

Biography:

Edmund M. Clarke received a B.A. degree in mathematics from the University of Virginia in 1967, a M.A. degree in mathematics from Duke University in 1968, and a Ph.D. degree in computer science from Cornell in 1976.  He taught at Duke University from 1976-1978 and at Harvard University from 1978-1982. Since 1982 he has been on the faculty in the Computer Science Department at Carnegie-Mellon University. In 1995 he became the first recipient of the FORE Systems Professorship, an endowed chair in the School of Computer Science. He was named a University Professor in 2008.

Dr. Clarke's interests include software and hardware verification and automatic theorem proving. In 1981 he and a graduate student, Allen Emerson, first proposed the use of Model Checking as a verification technique for finite state concurrent systems. His research group pioneered the use of Model Checking for hardware and software verification. In particular, his research group developed Symbolic Model Checking using BDDs, Bounded Model Checking using fast CNF satisfiability solvers, and pioneered the use of CounterExample-Guided-Abstraction-Refinement (CEGAR).  In addition, Clarke and his students developed the first parallel general resolution theorem prover (Parthenon), and the first theorem prover to be based on a symbolic computation system (Analytica).

Dr. Clarke is co-founder of the conference on Computer Aided Verification (CAV) and served on its steering committee for many years. He is the former editor-in-chief of Formal Methods in Systems Design.  He served on the editorial boards of Distributed Computing, Logic and Computation, and IEEE Transactions in Software Engineering. In 1995 he received a Technical Excellence Award from the Semiconductor Research Corporation. He was a co-recipient of the ACM Kanellakis Award in 1998.  In 1999 he received an Allen Newell Award for Excellence in Research from the Carnegie Mellon Computer Science Department.

In 2004 Dr. Clarke received the IEEE Harry H. Goode Memorial Award. He was elected to the National Academy of Engineering in 2005 for contributions to the formal verification of hardware and software correctness. He was a co-recipient of the 2007 ACM Turing Award for his role in developing Model Checking into a highly effective verification technology, widely adopted in the hardware and software industries. He received the 2008 CADE Herbrand Award for Distinguished Contributions to Automated Reasoning and a 2010 LICS Test-of-Time Award. In 2011 he was elected to the American Academy of Arts and Sciences. He received an Honorary Doctorate from the Vienna University of Technology in 2012. In 2013 he was awarded an Einstein Professorship by the Chinese Academy of Sciences. Dr. Clarke is a Fellow of the ACM and the IEEE, and a member of Sigma Xi and Phi Beta Kappa.