Download Jury´s citation

AWARD DECISION
INFORMATION AND COMMUNICATION TECHNOLOGIES
Madrid, January 11, 2016.
The jury in the eighth edition of the BBVA Foundation Frontiers of Knowledge Awards in the
Information and Communication category, formed by:
CHAIR OF THE JURY
Prof. Georg GOTTLOB
Professor
Computer Science Department
University of Oxford
United Kingdom
MEMBERS
Prof. Oussama KHATIB
Professor of Computer Science and Director of the
Robotics Laboratory
Stanford University
USA
Prof. Dr. Rudolf KRUSE
Professor
Faculty of Computer Science
Otto-von-Guericke University Magdeburg
Germany
Prof. Mateo VALERO
Director
Barcelona Supercomputing Center
Spain
Prof. Joos VANDEWALLE
Head of SCD Division
Department of Electrical Engineering
Katholieke Universiteit Leuven
Belgium
SECRETARY
Prof. Ramón LÓPEZ DE MÁNTARAS
Director
Artificial Intelligence Research Institute
Spanish National Research Council
Spain
Meeting together on January 11, 2016 in the offices of the BBVA Foundation in Madrid, Spain, in
order to deliberate and decide, have resolved to grant the BBVA Foundation Frontiers of
Knowledge Award in the Information and Communication Technologies category, in its eighth
edition, to the following candidate:
Professor Stephen Arthur COOK, Department of Computer Science, University of Toronto
Nominated by: Professor Sven Dickinson, Chair of Computer Science Department, University of
Toronto, Canada
Citation:
The BBVA Foundation Frontiers of Knowledge Award in the Information and Communication
Technologies category has been granted in this eighth edition to Professor Stephen Arthur Cook
from the University of Toronto, Canada, for his pioneering and most influential work on
computational complexity. Cook´s work plays an important role in identifying what computers
can and cannot solve efficiently. His concept of “NP-completeness” is considered as one of the
fundamental principles in computer science and has been making a dramatic impact on all fields
where complex computations are crucial.
In his seminal 1971 paper “The complexity of theorem proving procedures” Cook gave a
mathematical meaning to “efficiently computable”: A problem is efficiently computable if it is in
the class P of problems computable in deterministic polynomial time. He also gave a
mathematical meaning to “efficiently verifiable”, as in polynomial time, once a solution is given.
An efficiently verifiable problem, if at all solvable, can be solved with a guess-and check
procedure by first guessing a candidate for a solution (the so-called nondeterministic guessing
step), and then verifying efficiently that the guess is indeed a solution (the deterministic
polynomial-time checking step). Therefore the class of these problems is referred to as NP for
nondeterministic polynomial-time.
An example of a problem in the class NP is the well-known traveling salesperson problem: given a
number of cities and distances between each pairs of cities, is it possible to visit all cities by a tour
whose total travelled distance is smaller than a given bound? Once an appropriate tour has been
guessed, it is easy to verify in polynomial time that the total travel distance is below the desired
bound. Therefore this problem is in NP. However, with a growing number of cities this problem
becomes very hard to solve, and no efficient (polynomial time) algorithm for its solution is known.
For many other highly relevant computational problems in the class NP, no efficient algorithm is
known. However, it has so far been impossible to prove that these problems cannot be solved
efficiently and actually require exponential time for their solution. Cook established the now
well-known P versus NP question as to whether or not every decision problem that is efficiently
verifiable (in NP) can be made to be efficiently computable (in P) and conjectured (now known as
Cook’s Hypothesis) that P≠NP. The P versus NP question is now one of the seven million
“Millennium Prize Problems” listed by the Clay Mathematics Institute.
Cook showed that there are specific problems within the class NP to which all other problems in
NP can be efficiently transformed. These problems are referred to as NP-complete problems. If
one NP-complete problem can be solved in polynomial time, then all can. 45 years of combined
efforts by Computer Scientists and Mathematicians have not found any polynomial-time
algorithm for any NP-complete problem. Today there are literally thousands of known NP
complete problems in fields as diverse as biology (e.g. protein folding), physics, economics,
number theory, logic, optimization, and any field which has computational issues. NPcompleteness not only provides important guidelines to scientists but also to software engineers
and practitioners. Every undergraduate Computer Science curriculum typically includes lectures
about NP-completeness.
Although Cook’s seminal paper on NP-completeness is his best known contribution to theoretical
computer science, he has made equally deep and important contributions in the area of proof
complexity, in particular with regard to the complexity of propositional proof systems and
theories of bounded arithmetic.
Cook’s influence goes well beyond his own research. He is a spectacular teacher, an excellent
advisor, and an overall leader within the mathematical and computer science communities.
And in witness whereof sign the present document in the place and on the date first above
written.
CHAIR OF THE JURY
Prof. Georg Gottlob
MEMBERS
Prof. Oussama Kathib
Prof. Dr. Rudolf Kruse
Prof. Mateo Valero
Prof. Joos Vandewalle
SECRETARY
Prof. Ramón López de Mántaras