Charles Henry Bennett (born 1943)
is a
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate cau ...
,
information theorist
Information theory is the scientific study of the quantification, storage, and communication of information. The field was originally established by the works of Harry Nyquist and Ralph Hartley, in the 1920s, and Claude Shannon in the 1940s. ...
and
IBM Fellow
An IBM Fellow is an appointed position at IBM made by IBM's CEO. Typically only four to nine (eleven in 2014) IBM Fellows are appointed each year, in May or June. Fellow is the highest honor a scientist, engineer, or programmer at IBM can achiev ...
at
IBM Research
IBM Research is the research and development division for IBM, an American multinational information technology company headquartered in Armonk, New York, with operations in over 170 countries. IBM Research is the largest industrial research or ...
. Bennett's recent work at IBM has concentrated on a re-examination of the physical basis of information, applying
quantum physics to the problems surrounding information exchange. He has played a major role in elucidating the interconnections between physics and information, particularly in the realm of
quantum computation, but also in
cellular automata
A cellular automaton (pl. cellular automata, abbrev. CA) is a discrete model of computation studied in automata theory. Cellular automata are also called cellular spaces, tessellation automata, homogeneous structures, cellular structures, tessel ...
and
reversible computing
Reversible computing is any model of computation where the computational process, to some extent, is time-reversible. In a model of computation that uses deterministic transitions from one state of the abstract machine to another, a necessary co ...
. He discovered, with
Gilles Brassard, the concept of
quantum cryptography
Quantum cryptography is the science of exploiting quantum mechanical properties to perform cryptographic tasks. The best known example of quantum cryptography is quantum key distribution which offers an information-theoretically secure solution ...
and is one of the founding fathers of modern
quantum information theory
Quantum information is the information of the quantum state, state of a quantum system. It is the basic entity of study in quantum information theory, and can be manipulated using quantum information processing techniques. Quantum information re ...
(see
Bennett's four laws of quantum information).
Early career
Born in 1943 in New York City, Bennett earned a B.S. in Chemistry from
Brandeis University
, mottoeng = "Truth even unto its innermost parts"
, established =
, type = Private research university
, accreditation = NECHE
, president = Ronald D. Liebowitz
, ...
in 1964 and received his PhD from
Harvard in 1970 for molecular-dynamics studies (computer simulation of molecular motion) under
David Turnbull and
Berni Alder. At Harvard, he also worked for
James Watson one year as a teaching assistant about the genetic code. For the next two years he continued this research under
Aneesur Rahman at
Argonne National Laboratory (operated by the
University of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private university, private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park, Chicago, Hyde Park neighborhood. The University of Chic ...
).
After joining IBM Research in 1972, he built on the work of IBM's
Rolf Landauer
Rolf William Landauer (February 4, 1927 – April 27, 1999) was a German-American physicist who made important contributions in diverse areas of the thermodynamics of information processing, condensed matter physics, and the conductivity of disor ...
to show that general-purpose computation can be performed by a logically and thermodynamically reversible apparatus; and in 1982 he proposed a re-interpretation of
Maxwell's demon, attributing its inability to break the second law to the
thermodynamic
Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws of the ...
cost of destroying, rather than acquiring, information.
He also published an important paper on the estimation of free-energy differences between two systems, the
Bennett acceptance ratio
The Bennett acceptance ratio method (BAR) is an algorithm for estimating the difference in free energy between two systems (usually the systems will be simulated on the computer).
It was suggested by Charles H. Bennett in 1976.
Preliminaries
Tak ...
method.
Quantum cryptography
In collaboration with
Gilles Brassard of the
Université de Montréal
The Université de Montréal (UdeM; ; translates to University of Montreal) is a French-language public research university in Montreal, Quebec, Canada. The university's main campus is located in the Côte-des-Neiges neighborhood of Côte- ...
, Bennett developed a system of
quantum cryptography
Quantum cryptography is the science of exploiting quantum mechanical properties to perform cryptographic tasks. The best known example of quantum cryptography is quantum key distribution which offers an information-theoretically secure solution ...
, building on an idea of
Stephen Wiesner. Known as
BB84
BB84 is a quantum key distribution scheme developed by Charles Bennett and Gilles Brassard in 1984. It is the first quantum cryptography protocol. The protocol is provably secure, relying on two conditions: (1) the quantum property that informat ...
, the system takes advantage of the
uncertainty principle
In quantum mechanics, the uncertainty principle (also known as Heisenberg's uncertainty principle) is any of a variety of mathematical inequalities asserting a fundamental limit to the accuracy with which the values for certain pairs of physic ...
to allow secure communication between parties who share no secret information initially. With the help of
John Smolin, he built the world's first working demonstration of quantum cryptography in 1989.
His other research interests include
algorithmic information theory
Algorithmic information theory (AIT) is a branch of theoretical computer science that concerns itself with the relationship between computation and information of computably generated objects (as opposed to stochastically generated), such as str ...
, in which the concepts of information and randomness are developed in terms of the input/output relation of universal computers, and the analogous use of universal computers to define the intrinsic complexity or "logical depth" of a physical state as the time required by a universal computer to simulate the evolution of the state from a random initial state.
Teleportation
In 1993 Bennett and Brassard, in collaboration with others, discovered "
quantum teleportation", an effect in which the complete information in an unknown quantum state is decomposed into purely classical information and purely non-classical Einstein–Podolsky–Rosen (
EPR paradox
EPR may refer to:
Science and technology
* EPR (nuclear reactor), European Pressurised-Water Reactor
* EPR paradox (Einstein–Podolsky–Rosen paradox), in physics
* Earth potential rise, in electrical engineering
* East Pacific Rise, a mid-oc ...
) correlations, sent through two separate channels, and later reassembled in a new location to produce an exact replica of the original
quantum state
In quantum physics, a quantum state is a mathematical entity that provides a probability distribution for the outcomes of each possible measurement on a system. Knowledge of the quantum state together with the rules for the system's evolution i ...
that was destroyed in the sending process.
Later work
In 1995–1997, working with
Smolin,
Wootters,
DiVincenzo, and other collaborators, he introduced several techniques for faithful transmission of classical and quantum information through noisy channels, part of the larger field of quantum information and computation theory. Together with others he also introduced the concept of
entanglement distillation.
Bennett is a Fellow of the
American Physical Society and a member of the
National Academy of Sciences. He was awarded the 2008
Harvey Prize
Harvey Prize is an annual Israeli award for breakthroughs in science and technology, as well as contributions to peace in the Middle East granted by the Technion in Haifa.
History
The prize is named for industrialist and inventor Leo Harvey. T ...
by the
Technion and the 2006 Rank Prize in opto-electronics. In 2017 he received the
Dirac Medal
The Dirac Medal is the name of four awards in the field of theoretical physics, computational chemistry, and mathematics, awarded by different organizations, named in honour of Professor Paul Dirac, one of the great theoretical physicists of the 20 ...
of the
ICTP and in 2018 the
Wolf Prize in Physics
The Wolf Prize in Physics is awarded once a year by the Wolf Foundation in Israel. It is one of the six Wolf Prizes established by the Foundation and awarded since 1978; the others are in Agriculture, Chemistry, Mathematics, Medicine and Arts.
...
. In June 2019, he received the
Shannon Award
The Claude E. Shannon Award of the IEEE Information Theory Society was created to honor consistent and profound contributions to the field of information theory. Each Shannon Award winner is expected to present a Shannon Lecture at the following ...
and for 2019 the
BBVA Foundation Frontiers of Knowledge Award
The BBVA Foundation Frontiers of Knowledge Awards () are an international award programme recognizing significant contributions in the areas of scientific research and cultural creation. The categories that make up the Frontiers of Knowledge Awards ...
in Basic Sciences.
Bennett also co-runs a blog, ''The Quantum Pontiff'', with Steve Flammia and
Aram Harrow
Aram Wettroth Harrow (born 1980) is a professor of physics in the Massachusetts Institute of Technology's Center for Theoretical Physics.
Harrow works in quantum information science and quantum computing. Together with Avinatan Hassidim and Se ...
and hosted by Dave Bacon.
Private life
Bennett identifies himself as an atheist. Recalling a fond memory of the physicist
Asher Peres
Asher Peres ( he, אשר פרס; January 30, 1934 – January 1, 2005) was an Israeli physicist. He is well known for his work relating quantum mechanics and information theory. He helped to develop the Peres–Horodecki criterion for quantum en ...
, he writes:
[Charles H. Bennett's letter written to the family of Israeli physicist Asher Peres, fro]
a selection of the many letters of condolence sent to the Peres family during January 2005
References
External links
Charles Bennett's page at IBM site''The Quantum Pontiff'' blog
{{DEFAULTSORT:Bennett, Charles H.
Theoretical physicists
1943 births
Living people
Fellows of the American Physical Society
Members of the United States National Academy of Sciences
IBM Fellows
IBM Research computer scientists
Brandeis University alumni
Harvard University alumni
American atheists
Scientists from New York City
20th-century American engineers
21st-century American engineers
20th-century American physicists
21st-century American scientists
Science bloggers
Quantum information scientists
Wolf Prize in Physics laureates