Quantum theory, which best describes the underlying
properties of the material universe, and which we exploit
to marvellous effect in our everyday technology, was
born in the period 1924-1926, following several decades
of debate over whether the Newtonian, or classical,
description of matter and its interactions could explain
the world of the very small.
Quantum theory has a very disturbing property, however,
in that it is not a deterministic theory – in which a
future event could be predicted with certainty – but a
probabilistic theory – in which one could only speak of
the probability that a future event would occur. This
probabilistic interpretation, introduced by Max Born,
lay at the heart of Albert Einstein’s discomfort with
quantum mechanics, despite its many successes. He famously
commented to Born: ‘The theory produces a good deal but
… I am at all events convinced that (the Old One) does
not play dice.’ At the same time, the scientific community
was troubled by the philosophical foundations of quantum
mechanics, which were so difficult to understand that many
preferred to ignore them.
Queen’s University Belfast has had a long and very fruitful
relationship with quantum mechanics and its applications
since those early days, initially through individuals such
as Sir Harrie Massey, who came to Queen’s in 1933, before
moving to become professor in University College London
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– the academic link that this move created in atomic and
molecular physics is still strong today, 80 years later.
Also Sir David Bates, one of Massey’s PhD students, whose
career at Queen’s was key to the foundation of the ‘Belfast
School’, which educated generations of leaders in quantum
mechanics. I recall, while a PhD student in Manchester
in the mid-1970s, attending a conference in Queen’s during
which the Belfast Telegraph had a photograph of 15-20
professors from around the world – all trained here. John
Bell, as a Queen’s student in the late 1940s, was exposed
to scientists who were expert in the use and application
of quantum mechanics, which he put to good use in his
own career.
This exhibition of John Bell’s life and scientific legacy
shows that he was not only willing to wrestle with
these philosophical foundations but had the outstanding
intellect to frame a test of them. Later experiments,
described in the exhibition, showed that at a fundamental
level quantum particles are entangled and that Einstein’s
view of quantum mechanics was incorrect.
Perhaps the most surprising outcome of Bell’s work is
the development of quantum information theory which has
applications to cryptography and quantum computing, topics
covered in our public lecture series. In Queen’s, such
work is carried out in the Quantum Technology Group led by
Professor Mauro Paternostro in the School of Mathematics
and Physics. Bell’s scientific legacy is alive and well
at Queen’s and many other institutions worldwide.
We hope that this exhibition gives you some idea of
the enormous impact that John Bell’s ideas have had and
continue to have on the scientific and artistic communities,
and why some scientists rank him alongside Newton,
Maxwell and Einstein.
PROFESSOR TOM MILLAR
Dean of Engineering & Physical Sciences
JSB AS A STUDENT AT QUEEN’S UNIVERSITY, 1945
© Queen’s University Belfast
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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JSB AT SEMINAR AT THE
THEORY DIVISION, CERN, 1977
© CERN
LECTURES
Friday 7 November 2014
JOHN BELL AND BELFAST
PROFESSOR EMERITUS ANDREW WHITAKER
School of Mathematics & Physics
Wednesday 12 November 2014 SECURITY
IN A POST-QUANTUM WORLD
PROFESSOR MAIRE O'NEILL
Director of Research for Data Security Systems
Centre for Secure Information Technologies
Monday 17 November 2014
FROM JOHN BELL TO QUANTUM COMMUNICATION
AND
QUANTUM TELEPORTATION
PROFESSOR ANTON ZEILINGER
University of Vienna, whose research concerns the
fundamental aspects and applications of quantum entanglement
Wednesday 19 November 2014 LESS REALITY, MORE SECURITY
PROFESSOR ARTUR EKERT
University of Oxford, and the National University
of Singapore. Director of the Centre for Quantum
Technologies, he is best known as one of the inventors
of quantum cryptography.
Friday 21 November 2014
QUANTUMNESS
IN A CLASSICAL WORLD?
PROFESSOR MAURO PATERNOSTRO
School of Mathematics & Physics
All the lectures are free and will take place either in the Bell
Lecture Theatre or in the Emeleus Lecture Theatre at 6.30pm.
Further details can be found at www.naughtongallery.org
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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ART AND
BELL'S THEOREM
RICHARD BELL
RENATE BERTLMANN
GERALDINE COX
OLIVER JEFFERS
RORY JEFFERS
JONATHON KEATS
KEVIN KOPACKA
LUCY MCKENNA
PHILIP MUSSEN
AUSTRALIA
AUSTRIA
GREAT BRITAIN
UNITED STATES
NORTHERN IRELAND
UNITED STATES
GERMANY
IRELAND
NORTHERN IRELAND
Art that responds to science is about metaphors; the
connection of ideas and vocabulary from apparently very
different worlds in order to find a new resonance. All
artists mine their individual experience for visual
metaphors, but paradox and duality, the foundations
of quantum theory are also the fundamentals of the
artistic expression of human experience. The process
of experimentation in materials and methodology and the
constant act of construction and destruction to uncover a
new way of seeing are common to both scientific and artistic
endeavor. Like physics, art is inherent in nature.
Over the past 50 years, artists have used the evolution
of superposition or the quantum wave function from one
state to another as a useful metaphor for grasping the
immaterial and variable. John Stewart Bell’s legacy has
been the inspiration for the nine artists featured in this
exhibition. Some have worked directly from Bell’s life
and science and others have come to his work through the
championship of other scientists, authors and thinkers,
such as Robert Anton Wilson.
Renate Bertlmann, a friend of the Bell’s in Geneva,
worked from life, documenting his interactions with
RICHARD BELL, BELL’S THEOREM, 2002
© Milani Gallery, Brisbane
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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her husband Reinhold. Rory Jeffers has been inspired by
Bell’s own reference to his having “principles on Sunday”
in extrapolating an imagined thought-diary.
Some artists have investigated Bell’s scientific legacy
in the lab: Geraldine Cox, originally a physicist herself,
used her residency at Imperial College, London to explore
the manifestation of Bell’s theories in nature; Lucy
McKenna creates tessellated patterns from diagrams and
equations found on the desks of physicists at CERN.
Others manipulate the viewer into questioning their
perception of reality: Philip Mussen subverts the
archetypical medium of blackboard and chalk and embodies
the Bell’s theorem’s elegant equation in the title of his
piece; Kevin Kopacka uses sound and moving image to play
with the notion of the mysterious in everyday occurrences.
Conceptual artist and experimental philosopher, Jonathon
Keats’ installation invites the visitor to physically
participate in a quantum “marriage”, forever entangling
themselves with another outside any of the usual legal
or cultural matrimonial conventions.
Finally, artists have used John Stewart Bell’s science
to provoke and agitate. Oliver Jeffers’ trademark collage
technique and appropriated imagery confronts the viewer
with hidden variables applied to religious iconography.
Richard Bell’s Bell’s Theorem, one of contemporary
Australian art’s most significant works, is being shown
in Europe for the first time as part of this exhibition.
Using their shared names as a starting point, this is
the first in a powerful series of paintings using Bell’s
inequalities and ideas of non-locality to comment on
Australia’s racism towards Aboriginal people.
LUCY MCKENNA,
QUANTUM ENTANGLEMENT, 2014
This juxtaposition of art with science demonstrates the
common goals of visualising the invisible and saying the
unspeakable and reveals John Stewart Bell’s continuing
influence on contemporary art practice. It is hoped that
these works will themselves inspire further creative
thought, practice and, perhaps, physics.
Shan McAnena
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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JOHN STEWART BELL
1928_ Born 28 June, Tate’s Avenue, Belfast. His interest
in science from an early age earns him the nickname
“the Prof”.
1944_ Leaves Belfast Technical High School
Hired as a junior laboratory assistant in the
Physics department at Queen’s University Belfast
under its professors Karl Emeleus and Robert Sloane.
1945_ Receives a small grant from the Co-operative
society and becomes student at Queen’s.
1948_ Graduates with a First Class Bachelor’s Degree
in Experimental Physics.
1949_ Receives a First Class Bachelor’s degree
in Mathematical Physics.
Joins the accelerator design group at the
Telecommunications Research Establishment
at Malvern, Worcestershire.
Meets Mary Ross, a member of the design group.
1951_ Design group at Malvern moves to Harwell,
Oxfordshire to become part of the Theoretical
Physics division at the Atomic Energy Research
Establishment
1953_ Granted a year’s leave of absence from Harwell to
work in the department of Mathematical Physics at
the University of Birmingham.
1954_ Marries Mary Ross.
1955_ Publishes the paper Time reversal in field theory,
the basis of his PhD.
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
1956_ Awarded PhD in Physics by the University
of Birmingham.
1960_ John and Mary move to the European Council
for Nuclear Research (CERN) based in Geneva,
Switzerland.
1963_ Year-long leave of absence spent in the USA at
the Stanford Linear Accelerator Centre, California,
the University of Wisconsin-Madison and Brandeis
University, Massachusetts.
1964_ Publishes the paper On the Einstein-Podolsky-Rosen
Paradox and posits Bell’s Inequality.
1972_ First of many experiments that have shown a
violation of Bell's Inequality
1981_ Publishes the paper Bertlmann’s socks and the
nature of reality where he compared the EPR paradox
with Reinhold Bertlmann’s socks: if you observe one
sock to be pink you can predict with certainty that
the other sock is not pink.
1988_ Receives honorary degrees from Queens University
Belfast and Trinity College, Dublin
1989_ Receives the Dannie Heinemann Prize for
Mathematical Physics and the Hughes Medal
"For his outstanding contributions to our
understanding of the structure and interpretation
of quantum theory, in particular demonstrating
the unique nature of its predictions"
1990_ October, dies unexpectedly of a cerebral
haemorrhage in Geneva, Switzerland. It is widely
believed that Bell would have been awarded a
Nobel Prize if he had lived.
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QUANTUM
BEFORE BELL’S
THEOREM
Quantum theory is the theoretical basis of most of modern
physics; it explains the nature and behaviour of matter
and energy on the atomic and subatomic level.
1900_
1905_
From study of radiation of energy from hot objects,
Max Planck deduces that the energy is emitted in
discrete units or quanta.
From the experimental results for the
photoelectric effect, Albert Einstein shows that
light has a particle-like nature, the particles
being called photons, as well as its longestablished wavelike nature
1913_
Niels Bohr is the first to apply quantum theory
to atoms
1924_
Louis de Broglie suggests that electrons have a
wavelike nature as well as their long-established
particle-like nature.
1925/6_ Werner Heisenberg and Erwin Schrödinger produce
alternative versions of the new complete theory of
quantum mechanics. Heisenberg’s is based on arrays
of quantities – matrix mechanics, Schrödinger’s on
waves – wave mechanics.
1927_
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Max Born introduces probabilities into quantum
mechanics
ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
1927_
1928_
1932_
Werner Heisenberg proposes that precise
simultaneous measurement of the position and
momentum of a particle is impossible. The more
precisely the value of one is measured, the more
uncertain must be the value of the other.
Bohr outlines his framework of complementarity,
known as the Copenhagen interpretation of quantum
theory.
John von Neumann produces a mathematical ‘proof’
that there could be no hidden variables in quantum
mechanics.
1935_ Albert Einstein and his colleagues Boris Podolsky
and Nathan Rosen (EPR) describe a situation in
which the properties of each of two particles are
undetermined but still totally correlated with
those of the other particle.
Erwin Schrödinger called this type of behaviour
entanglement. Measurement of a property of one
gives information of the corresponding property
of the other, even though the particles may be
separated by a long distance.
Schrödinger introduces his famous cat-state
paradox.
1952_
David Bohm produces a hidden variable theory
of quantum theory.
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JOHN BELL & MARTINUS VELTMAN
AT CERN, 1973
© CERN/Emilio Segré archive, AIP
THE COPENHAGEN INTERPRETATION
The so-called Copenhagen interpretation of quantum
theory is a name given to the rather complex set of ideas
presented by Niels Bohr. Those most involved in preaching
the ‘gospel’ of Copenhagen were Bohr himself, Heisenberg
and Wolfgang Pauli.
For many years the ideas were taken as absolutely
standard, the most important challenge being that of
Einstein Podolsky Rosen (EPR) in 1935. From the 1960s
John Bell criticized the interpretation vigorously,
and largely as a result of this, several rival
interpretations have come to the fore, including
the many worlds interpretation.
The Copenhagen interpretation says that you can only
consider the value of a quantity at a measurement, so
physics does not describe objective reality but only
analyses the results of measurements. Since totally
different experimental arrangements are required to
measure position and momentum they must not be considered
simultaneously. Position and momentum are described as
complementary variables. Similarly wavelike and particlelike descriptions of a physical system are complementary;
one may use one or the other but not both.
The Copenhagen interpretation bans any thought of hidden
variables, additional facts about the system over and
above that provided by wave-function, which might provide
knowledge about the system between measurements.
Bohr insisted that the measurement apparatus must be
treated according to the pre-quantum laws of Newton, but
the observed system of atoms, electrons and so on must be
analyzed using quantum theory. But there is no criterion
for where the division between classical and quantum
theory lies. John Bell called this the shifty split.
Bohr had an alternative argument to this conceptual
analysis – the more physical suggestion that ‘the
measurement disturbs the system’. EPR showed that
this argument did not work.
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
John Bell was totally dissatisfied with the Copenhagen
interpretation. He thought that physics should describe
an objective reality not just describe the results of
measurements, and that the inclusion of hidden variables
could help to provide values for physical quantities
between measurements. He argued against the shifty split
for forty years.
EPR
In 1935 Albert Einstein and his colleagues Boris Podolsky
and Nathan Rosen designed a thought experiment in which
a pair of quantum systems may be described by a single
wave-function. The results of measurements of properties
of the two systems are intimately connected, or entangled.
In David Bohm’s example, the wave-functions of two
electrons A and B are entangled even though the two
electrons may actually be separated by a long distance.
If we were to measure the spin angular momentum of
particle A, our result must be either plus or minus.
If we get the result +, the corresponding value for
particle B must immediately become -; if we get - for A,
the value for B must become +.
This led to two possible scenarios:
• each electron had these values before any measurement.
The Copenhagen interpretation does not allow this; it
may be described as including hidden variables in the
analysis or restoring an objective reality.
• an influence travels instantaneously from particle A
to particle B. This apparently contradicts the theory
of special relativity which suggests that nothing can
travel faster than the speed of light.
Einstein approved of objective reality and also special
relativity and his unquestioned conclusion was to agree
with the first scenario.
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© Kurt Gottfried
BELL IN
BELFAST
John Stewart Bell was born on July 28 1928, the eldest son
of John and Annie Bell of Tate’s Avenue, Belfast and to
avoid confusion he was always known by his middle name at
home. The second of four children, John Stewart was the
only child of this working class family that was able to
go to secondary school and he matriculated from Belfast
Technical High School (now Belfast Metropolitan College)
in 1944.
Having applied for several jobs without success, at the
age of sixteen John Stewart was offered a position as
a laboratory technician in the Physics department at
Queen’s. Encouraged by the academic staff who recognised
his potential, Bell used money saved from his employment
to enrol for a degree course and went on to graduate with
a first-class degree in experimental physics in 1948. The
following year he achieved a second degree in mathematical
physics.
HARWELL
Encouraged by the crystallographer Paul Peter Ewald, in
1949 Bell joined the Atomic Energy Research Establishment
(AERE) near Harwell in Oxfordshire, where he met fellow
physicist Mary Ross who was to become his wife. They both
worked on the theory of particle accelerators. Bell made
crucial contributions to the important discovery of strong
focussing, the principle that the net effect on a particle
beam of charged particles passing through alternating field
gradients is to make the beam converge.
TATE’S AVENUE, BELFAST 1915
Public Record Office of Northern Ireland
ref: LA/7/8/HF/4/163
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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MARY & JOHN AT STONEHENGE
© Mary Bell
CERN
In 1960 John and Mary moved to the Centre for European
Nuclear Research (CERN) in Geneva where he was to remain
until his death. Whilst at CERN he published around eighty
papers on high-energy physics and quantum field theory.
In 1967 he made the important suggestion that the weak
nuclear interaction should be described by a gauge theory.
It is now known that all interactions, gravitational,
electromagnetic, and weak and strong nuclear should be
described in this way.
In 1969, together with Roman Jackiw, he discovered the
subject of anomalies; the coming of quantum theory led to
breaking of classical symmetries. Their original paper has
been the catalyst for an enormous amount of important work
in this field and has been cited more than any of Bell’s
famous quantum papers.
Image Right:
JSB’S DESK AT CERN
© Renate Bertlmann
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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JSB’S ID PHOTO,
STANFORD UNIVERSITY, 1964
© SLAC National
Accelerator Laboratory
BELL’S
THEOREM
Whilst on sabbatical from CERN, visiting universities in
the USA, Bell made his greatest contribution to quantum
theory. Published on November 4th 1964, in a new and
short-lived journal called Physics, On the Einstein
Podolsky Rosen paradox appeared to disprove Einstein’s
theory of relativity with Bell’s non-locality theory.
Using elegant mathematics, Bell's theorem asserts that
if certain predictions of quantum theory are correct
then our world is non-local. This means that sub-atomic
particles can interact even if they are too far apart
in space and too close together in time for them to be
connected even by signals moving at the speed of light.
The paper was initially overlooked but later discovered
by a group of young physicists, experimentally tested and
named as Bell’s inequality or Bell’s Theorem. His work has
reinvigorated study of the foundations of quantum theory
and has led to many significant and interesting ideas.
Unassuming and modest about his own work, Bell is
remembered for his intellectual precision, integrity,
and generosity, as well as a keen Ulster sense of humour.
He was a frequent visitor to Belfast, where his family
remained.
John Bell died of a stroke at his home 1 October 1990
in Geneva, aged 62. Describing him as one of the top
ten physicists of the twentieth century, the Institute of
Physics mounted a plaque commemorating his pioneering work
on the old physics building in the quadrangle at Queen’s
in 2002. The acknowledgement of Bell’s contribution
at CERN includes the naming of a street name after him
in Geneva.
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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Bell’s theorem asserts that if certain predictions of
quantum theory are correct then our world is “non-local”.
This means that sub-atomic particles can interact even
if they are too far apart in space and too close together
in time for them to be connected even by signals moving
at the speed of light.
PHILIP MUSSEN,
p(a,c) – p(b,a) – p(b,c) ≤ 1, 2014
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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© Renate Bertlmann
QUANTUM
AFTER
BELL
Quantum theory currently provides the most accurate
predictions for frontier experiments. It can be used
to describe the physics of atoms, molecules, nuclei,
elementary particles, solids and plasmas and to handle
optics at the single photon level.
Many of the concepts studied by Bell and those who
developed his work have formed the basis of the new
subject area of quantum information theory, which includes
such topics as quantum computing, quantum communication,
and quantum cryptography. The subject is one of the most
important growth areas in science in the 21st century.
JOHN STEWART BELL PRIZE
In 2008, the John Stewart Bell Prize was created by the
Centre for Quantum Information and Quantum Control at the
University of Toronto. The award recognizes major advances
relating to the foundations of quantum mechanics and to the
applications of these principles. The first prize-winner
was Nicolas Gisin and subsequent medals have been awarded
to Sandu Popescu, Michel Devoret and Robert Schoelkopf.
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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QUANTUM AT QUEEN’S
Queen’s is currently at the forefront of the research
in astrophysics, plasma physics, material science, and
theoretical quantum physics, in particular atomic/
molecular physics and quantum information processing.
Research in theoretical quantum physics at Queen’s focuses
on the interaction between light or electrons and atoms,
the description of anti-matter, the production of atomic
data of astrophysical relevance and, in particular, the
study of the possibilities for the establishment of a new
generation of technological devices based on quantum.
Work in this topic often exploits Bell’s achievements.
Queen’s quantum researchers put in place Bell’s theorem
to understand what sets the quantum world apart from
the classical one and enforce quantum features in large
systems.
GERALDINE COX, STILL FROM
NATURE’S IMAGINATION, 2013
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL
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Published on the occasion of the exhibition
ACTION AT A DISTANCE:
THE LIFE AND LEGACY OF JOHN STEWART BELL
At the Naughton Gallery, Queen’s University Belfast
5-30 NOVEMBER 2014
Curators
Professor Tom Millar, Dean of Engineering & Physical Sciences
Professor Andrew Whitaker, School of Mathematics & Physics
Professor Mauro Paternostro, School of Mathematics & Physics
Shan McAnena, The Naughton Gallery
Assistant Curators
Ben Crothers
Stephen Doyle
Paul McAlorum
With thanks to
Mary Bell
Reinhold Bertlmann
Renate Bertlmann
Nick Herbert
CERN
Royal Irish Academy
University of Birmingham
Rory Jeffers
Milani Gallery, Brisbane
Modernism, San Francisco
Lazarides, London
Front cover and inside front cover:
John Bell commenting the famous Bell’s Inequalities 1982 ©CERN
Inside Back cover:
Nick Herbert, Bell’s Theorem Blues, 2014
©2014 the artists and the Naughton Gallery, Queen’s University Belfast
All rights reserved. No part of this book may be produced, stored in a
retrieval system, or transmitted in any form or by any means, without
the permission of the artist, author, photographer and publisher.
Queen’s University
Belfast, BT7 1NN
+44(0)28 90973580
art@qub.ac.uk
www.naughtongallery.org
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ACTION AT A DISTANCE: THE LIFE AND LEGACY OF JOHN STEWART BELL