Building blocks of matter a supplement to the macmillan encyclopedia of physics john s rigden

B UILDING
B LOCKS OF
M ATTER


EDITORIAL BOARD

Editor in Chief
John S. Rigden
American Institute of Physics

Editors
Jonathan Bagger
Johns Hopkins University
Roger H. Stuewer
University of Minnesota


B UILDING
B LOCKS OF
M ATTER
A Supplement to the
MACMILLAN
ENCYCLOPEDIA OF PHYSICS

John S. Rigden
Editor in Chief


Building Blocks of Matter: A Supplement to the Macmillan Encyclopedia of Physics

John S. Rigden, Editor in Chief

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Library of Congress Cataloging-in-Publication Data
Building blocks of matter : a supplement to the Macmillan encyclopedia
of physics / edited by John S. Rigden.
p. cm.
Includes bibliographical references and index.
ISBN 0-02-865703-9 (hardcover : alk. paper)
1. Particles (Nuclear physics) I. Rigden, John S. II. Macmillan
encyclopedia of physics.
QC793.2 .B85 2003
539.7’2—dc21
2002013396

Printed in the United States of America
10 9 8 7 6 5 4 3 2 1

CONTENTS

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Reader’s Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
List of Articles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
List of Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
Common Abbreviations and Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxix
Building Blocks of Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Time Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503
Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 509
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 515

v


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vi


PREFACE

The concepts and ideas of elementary particle physics
are abstract, and they are typically expressed in the
language of mathematics. However, the goal of elementary particle physics is very simple, and all the efforts of elementary particle physicists are directed
toward that simple goal: to identify the basic building blocks of matter and to understand how they interact to produce the material world we observe.

that may be unknown to the reader, both in the field
of physics and in related sciences. A list of common
abbreviations and acronyms at the beginning of the
book is included to aid readers unfamiliar with those
used in the book. Numerous tables, figures, illustrations, and photographs supplement the information
contained within the articles and provide visual tools
to better understand the material presented.

This encyclopedia contains articles intended for
a broad audience of general readers and is designed
to edify and give readers an appreciation for one of
the most active and productive areas of physics
throughout the twentieth century and to the present
time. On the one hand, most of the articles have

been written in ordinary language and provide a
solid base in particle physics concepts and history for
those who are new to the field. On the other hand,
some topics in particle physics are difficult to express
in everyday words, and in the articles on such topics,
symbols appear and even an occasional equation.
Even these articles, however, are written so that the
reader with little physics background can capture a
general sense of the topic covered.

Entries are arranged alphabetically and include
extensive cross-references to refer the reader to additional discussions of related topics. In each article, a bibliography directs the reader to books,
articles, and Web sites that provide additional
sources of information. The articles themselves focus on particular topics that, taken together, make
up the intellectual framework called elementary particle physics. Articles such as those on accelerators,
quarks, leptons, antimatter, and particle identification provide a working base for the study of particle
physics. Articles such as those on quantum chromodynamics, neutrino oscillations, electroweak symmetry breaking, and string theory bring readers to
subjects that fill the conversations of contemporary
particle physicists. Finally, articles such as those on
the cosmological constant and dark energy, supersymmetry, and unified theories discuss the key topics replete with many exciting questions left to be
answered.

Several features of the encyclopedia are designed to help the general reader navigate the language of physics and mathematics included in the
articles on the more complex topics. A glossary in
the back of the book provides definitions for terms

vii


PREFACE

Articles also detail the history of particle physics,
including the discovery of specific particles, such as
the antiproton and the electron. In addition to the
historical articles, a time line is included to provide
an overview of the development of the field of particle physics. This time line of research and development in what is now called particle physics extends
back almost three millennia. The time line demonstrates the commanding grip that the desire to identify the basic building blocks of matter has had on
the minds of past and present scientists. Biographical articles of physicists who have made seminal contributions to our understanding of the material world
complete the encyclopedia’s coverage of the history
of particle physics. The selection of physicists for the
biographies was based on the desire to provide a historical background for the topics presented in this
encyclopedia, and so no living physicist was included.
Since experimentation is a vital part of particle
physics, detailed articles discuss the technologies
used to discover particles, including current accelerator types and subsystems. Articles also profile the
international laboratories that house these accelerators, describing experiments, both historic and
current, conducted at these labs. Articles on case
studies are included to provide the reader with
more in-depth information as to how these technologies contribute to the past and continuing search
for particles.
Particle physics both affects and is affected by
other sciences as well as by the political and philosophical environment. Articles discuss the interac-

viii

tion of particle physics and cosmology, astrophysics,
philosophy, culture, and metaphysics. Also included
are articles describing the spin-off technologies created in the search for particles as well as the funding of this research.
A reader’s guide in the beginning of the encyclopedia arranges the topics into broad categories
and thereby helps organize the array of individual

entries into a comprehensive field of study. Additionally, the article on elementary particle physics
provides an overview of the field and its current
questions.
The authors of the articles contained in this encyclopedia work in the top particle physics laboratories and are professors at renowned colleges and
universities. Not only does this encyclopedia provide
a comprehensive coverage of the field of particle
physics, but it also brings together articles from the
top members of the physics and scientific community.
This collection of articles would not have been
possible without the effort of those who contributed,
and I thank each of the authors. Jonathan Rosner,
University of Chicago, has responded to personal requests I made of him, and I thank him. Also, I am
grateful to both editors, Jonathan Bagger, Johns
Hopkins University, and Roger H. Stuewer, University of Minnesota, for their work and advice. Lastly,
the Macmillan editor, Deirdre Graves, has been devoted in her assistance throughout the project. We,
the editors, thank her.
John S. Rigden

BUILDING BLOCKS OF MATTER


INTRODUCTION

Physicists distinguish between classical and modern
physics. The classical era began in the Scientific Revolution of the seventeenth century and extended
throughout the eighteenth and most of the nineteenth centuries. By then there were rumblings
among some prominent physicists that their subject
was complete, that no more basic physics remained
to be discovered. Then, in 1895, Wilhelm Conrad
Röntgen discovered X rays, and abruptly, although

perhaps unknowingly, the modern era of physics began. During the following year Henri Becquerel discovered radioactivity, and in 1897 the work of several
physicists culminated in the discovery of the electron,
which is generally credited to J. J. Thomson. With
the first subatomic particle, the electron, to account
for, physicists knew that a new era was under way.

measurements had established that hydrogen was the
least massive of the chemical elements, and in 1815
William Prout proposed that hydrogen was the building block of all the chemical elements. Prout’s idea
had supporters through the nineteenth century, but
it was finally discredited with the discovery of isotopes
early in the twentieth century.

The idea of basic building blocks of matter is at
least 2,600 years old. In the sixth century B.C.E.
Thales proposed that all things reduced to water,
and, coming out of the Greek-Roman eras and for
centuries to come, the four basic elements were
thought to be earth, water, fire, and air. The atomic
hypothesis, originating in the fifth century B.C.E., lingered in the background for centuries until experimental support, through the work of eighteenth- and
nineteenth-century chemists, brought atoms to the
fore as the basic building blocks of matter. By the
early years of the nineteenth century, quantitative

What makes a particle elementary? Simply put,
it contains no parts. The electron has no hidden constituents. The electron is elementary. The proton,
long considered to be an elementary particle, does
have parts—three quarks. The proton is not elementary. There are currently twelve elementary particles that physicists believe make up the observable
matter throughout the universe: six quarks—up,
down, charm, strange, top, and bottom—and six

leptons—electron, electron neutrino, muon, muon
neutrino, tau, and tau neutrino—all of which fit
nicely into three groups, called generations, each

One of the major themes of twentieth-century
physics, a spectacular period in the history of physics,
has been the continuation, although greatly intensified, of the ancient quest to identify and understand
the fundamental constituents of matter. The electron, discovered in 1897, was the first elementary particle, and, after a century that saw “elementary”
particles come and go with great profusion, the electron was and remains truly elementary.

ix


INTRODUCTION

consisting of two quarks and two leptons. The first
generation consists of the four lightest particles—the
up and down quarks and the electron and the electron neutrino—which are the particles responsible
for ordinary matter as we currently know it. The composition of dark matter remains a mystery. The particles of the second and third generations are
successively more massive, and these heavier particles are believed to have played roles during the moments following the Big Bang. The twelve elementary
particles make up the Standard Model.
The electron and proton were discovered by experimental set-ups built on a small table. By contrast,
quarks were discovered by means of vast accelerators with dimensions measured in miles and with
subsystems that dwarfed the physicists walking among
them. The century’s trend toward larger and larger
accelerators was necessitated by the need for higher
and higher energies. In turn, higher energies were
required to probe the innards of particles such as
the proton as well as to create new particles with substantial masses such as the W and Z as well as the
top quark.

The objective of elementary particle physics is
twofold: to establish the identity of all the elementary particles of nature and to determine the means
by which the elementary particles interact so as to
give rise to our material world. Four basic interactions, or forces, have been identified: gravitational,
electromagnetic, weak, and strong. Each of these
four forces is transmitted between particles by the
exchange of a force-carrying particle; the photon
transmits the electromagnetic force, W and Z particles the weak force, and gluons the strong force. The
graviton, which has not been established experimentally, is assumed to transmit the gravitational
force. With the twelve “matter” particles and the four
“interaction” particles, the behavior of all the observed matter in the universe can be described.
The ability to describe ordinary matter in terms
of a few basic entities is a triumph of contemporary
physics. In this remarkable process, however, physicists have moved toward a new threshold that portends
stunning insights into the physical world—insights
whose outlines can be observed, but only dimly. As is
always true, good science raises profound questions.
Is space three-dimensional or are there hidden di-

x

mensions hovering within our intellectual and experimental reach? Dark matter is a reality, but what is it?
Dark matter pulls our universe together, but dark energy pushes it apart. What is dark energy? Will the expansive effect of dark energy override the contractive
effect of dark matter? Why do the elementary particles have their particular masses? Will the Higgs boson bring understanding to this question? Gravitation
remains to be unified with the other basic interactions.
What will be required to accomplish this unification?
The answers to such questions may transform the conceptual landscape of physics and, in the process, fundamentally alter the way humans view their world.
During the past two decades, nature’s extremes
have been linked. At one extreme are the elementary particles with their infinitesimal sizes and masses;
at the other extreme is the universe with its incomprehensibly immense size and mass. The detailed

knowledge of elementary particles accumulated over
the past century has illuminated events immediately
following the Big Bang and has provided a reasonable explanation of how the universe evolved from
the zero-of-time to its current state fifteen billion
years later. The physics of elementary particles has
joined hands with cosmology, and together they have
brought knowledge and understanding to a level that
could not have been imagined when the electron was
first observed in 1897. Of course, many questions,
major questions, await answers; and many details, significant details, await elaboration. Good science
begets good questions.
At a practical level, particle physics has dramatically changed contemporary culture. Many of the
electronic methods that drive modern societies and
many of the computer powers that are now omnipresent were developed to meet the stringent demands of detecting and following events in the
unseen domain where the elementary particles blink
in and out of existence. The international character
of elementary physics, with team members located in
laboratories around the globe, required new and efficient ways of communication. The World Wide Web
was invented by elementary particle physicists at
CERN, the accelerator laboratory in Switzerland, to
exchange information quickly and accurately. Many
other contributions to society have their origins in
accelerator laboratories.

BUILDING BLOCKS OF MATTER


INTRODUCTION

Particle physics has had a profound influence on

scientific explanation. For much of the twentieth
century, explanations have been sought by reducing
complex systems to their simplest parts. Although no
one can deny the fruitfulness of this approach and
the great appeal of its explanations, it remains an
open question whether the simple parts can meet the
challenges ahead. Do new phenomena emerge with
complexity that cannot be understood in terms of

BUILDING BLOCKS OF MATTER

the basic interactions between nature’s simplest particles? Indeed, all material systems consist of elementary particles, but as systems move up the ladder
of complexity, are there threshold rungs that break
the explanatory line of logic back down to the particles? Only further scientific experimentation will
provide the answer.
John S. Rigden

xi


READER’S GUIDE

Accelerator Laboratories
Beijing Accelerator Laboratory
Brookhaven National Laboratory
Budker Institute of Nuclear Physics
CERN (European Laboratory for Particle Physics)
Cornell Newman Laboratory for Elementary Particle Physics
DESY (Deutsches Elektronen-Synchrotron Laboratory)
Fermilab

Japanese High-Energy Accelerator Research Organization, KEK
SLAC (Stanford Linear Accelerator Center)
Thomas Jefferson National Accelerator Facility

Accelerator Subsystems and Technologies
Beam Transport
Cooling, Particle
Detectors
Extraction Systems
Injector System

Accelerators, Fixed-target: Proton
B Factory
Cyclotron
Z Factory

Astrophysics and Cosmology
Astrophysics
Big Bang
Big Bang Nucleosynthesis
Cosmic Microwave Background Radiation
Cosmic Rays
Cosmic Strings, Domain Walls
Cosmological Constant and Dark Energy
Cosmology
Dark Matter
Hubble Constant
Inflation
Neutrino, Solar
Quark-Gluon Plasma

Universe

Basic Interactions
Accelerator Types
Accelerators,
Accelerators,
Accelerators,
Accelerators,
Accelerators,

Colliding Beams: Electron-Positron
Colliding Beams: Electron-Proton
Colliding Beams: Hadron
Early
Fixed-target: Electron

Basic Interactions and Fundamental Forces
Planck Scale

Biographies
Anderson, Carl D.
Chadwick, James

xiii


READER’S GUIDE

Dirac, Paul
Einstein, Albert

Fermi, Enrico
Feynman, Richard
Kendall, Henry
Lawrence, Ernest Orlando
Noether, Emmy
Pauli, Wolfgang
Reines, Frederick
Rutherford, Ernest
Salam, Abdus
Schwinger, Julian
Thomson, Joseph John
Tomonaga, Sin-itiro
Wigner, Eugene
Wilson, Robert R.
Wu, Chien-Shiung
Yukawa, Hideki

Case Studies
Case Study: Gravitational Wave Detection, LIGO
Case Study: LHC Collider Detectors, ATLAS and
CMS
Case Study: Long Baseline Neutrino Detectors,
K2K, MINOS, and OPERA
Case Study: Super-Kamiokande and the Discovery
of Neutrino Oscillations

Detectors
Detectors and Subsystems
Detectors, Astrophysical
Detectors, Collider

Detectors, Fixed-target
Detectors, Particle
Supernovae

Experiments as Case Studies
Experiment:
Experiment:
Experiment:
Experiment:

Discovery of the Tau Neutrino
Discovery of the Top Quark
gϪ2 Measurement of the Muon
Search for the Higgs Boson

Historical Articles
Antiproton, Discovery of
Eightfold Way
Electron, Discovery of

xiv

Muon, Discovery of
Neutrino, Discovery of
Neutron, Discovery of
Positron, Discovery of
Quarks, Discovery of
Radioactivity, Discovery of
SSC

Particle Physics
Computing
Particle Identification
Particle Physics, Elementary
Outlook

Particle Physics and Culture
Benefits of Particle Physics to Society
Culture and Particle Physics
Funding of Particle Physics
Influence on Science
International Nature of Particle Physics
Metaphysics
Philosophy and Particle Physics

Particles
Atom
Axion
Boson, Gauge
Boson, Higgs
Charmonium
Hadron, Heavy
J/␺
Lepton
Neutrino
Quarks
Resonances

Physical Concepts
Antimatter

Broken Symmetry
Conservation Laws
Energy
Energy, Center-of-Mass
Energy, Rest

BUILDING BLOCKS OF MATTER


READER’S GUIDE

Feynman Diagrams
Higgs Phenomenon
Momentum
Particle
Quantum Statistics

Physical Processes
Annihilation and Creation
Asymptotic Freedom
Electroweak Phase Transition
Jets and Fragmentation
Neutrino Oscillations
Parity, Nonconservation of
Phase Transitions
Quantum Tunneling
Radiation, Cherenkov
Radiation, Synchrotron
Radioactivity
Renormalization

Scattering
Virtual Processes

BUILDING BLOCKS OF MATTER

Physical Theories
Gauge Theory
Grand Unification
Lattice Gauge Theory
Quantum Chromodynamics
Quantum Electrodynamics
Quantum Field Theory
Quantum Mechanics
Relativity
Standard Model
String Theory
Technicolor
Unified Theories

Symmetries
CKM Matrix
CP Symmetry Violation
Electroweak Symmetry Breaking
Family
Flavor Symmetry
SU(3)
Supersymmetry
Symmetry Principles

xv

LIST OF ARTICLES

A

Antimatter
Dwight E. Neuenschwander

Accelerator

Antiproton, Discovery of
Elizabeth Paris

Gerald F. Dugan

Accelerators, Colliding Beams:
Electron-Positron
Raphael Littauer
David Rice

Accelerators, Colliding Beams:
Electron-Proton

Astrophysics
Virginia Trimble

Asymptotic Freedom
George Sterman

Atom
Guy T. Emery

Axion

David H. Saxon

Pierre Sikivie

Accelerators, Colliding Beams: Hadron
Gordon Fraser

Accelerators, Early

B

Robert W. Seidel

Accelerators, Fixed-target: Electron
William K. Brooks Jr.

Accelerators, Fixed-target: Proton
John Marriner

Anderson, Carl D.
William H. Pickering

Annihilation and Creation
Lewis Ryder

B Factory
Natalie Roe

Basic Interactions and Fundamental Forces
Roberto Peccei

Beam Transport
Michael J. Syphers

Beijing Accelerator Laboratory
Frederick A. Harris
Zhipeng Zheng

xvii


LIST OF ARTICLES

Benefits of Particle Physics to Society

Computing

Frank Wilczek

Big Bang

Bebo White

Conservation Laws

Joseph I. Silk

Big Bang Nucleosynthesis

Kenneth W. Ford

Cooling, Particle

Roger K. Ulrich

Boson, Gauge
Sally Dawson

John Marriner

Cornell Laboratory for Elementary Particle
Physics
Karl Berkelman

Boson, Higgs
Howard E. Haber

Cosmic Microwave Background Radiation
Suzanne T. Staggs

Broken Symmetry
John F. Donoghue

Cosmic Rays
C. Jake Waddington

Brookhaven National Laboratory
Robert P. Crease

Cosmic Strings, Domain Walls
Stephen G. Naculich

Budker Institute of Nuclear Physics
Alexander N. Skrinsky

Cosmological Constant and Dark Energy
Lawrence M. Krauss

Cosmology
Helge Kragh

C

CP Symmetry Violation
Jonathan L. Rosner

Case Study: Gravitational Wave Detection,
LIGO
Neil Ashby

Case Study: LHC Collider Detectors, ATLAS
and CMS

Culture and Particle Physics
John Polkinghorne

Cyclotron
Benjamin Bayman

Howard A. Gordon

Case Study: Long Baseline Neutrino Detectors,
K2K, MINOS, and OPERA
Stanley G. Wojcicki

Case Study: Super-Kamiokande and the
Discovery of Neutrino Oscillations
Henry W. Sobel

CERN (European Laboratory for Particle
Physics)
Maurice Jacob

Chadwick, James
Roger H. Stuewer

Charmonium
Mark J. Oreglia

CKM Matrix
JoAnne Hewett

xviii

D

Dark Matter
Keith Olive

DESY (Deutsches Elektronen-Synchrotron
Laboratory)
Paul Söding

Detectors
Stephen Pordes

Detectors and Subsystems
Paul Grannis

Detectors, Astrophysical
Steven Ritz

BUILDING BLOCKS OF MATTER


LIST OF ARTICLES

Detectors, Collider

Extraction Systems

David Hitlin

John Marriner

Detectors, Fixed-target

Kevin McFarland

Detectors, Particle
L. Donald Isenhower

F

Devices, Accelerating
William A. Barletta

Family
Pierre Ramond

Dirac, Paul
Helge Kragh

Fermi, Enrico
Albert Wattenberg

Fermilab
Adrienne W. Kolb

E

Feynman Diagrams
Lewis Ryder

Eightfold Way
Jonathan L. Rosner

Feynman, Richard
Silvan S. Schweber

Einstein, Albert
Michel Janssen

Flavor Symmetry
Benjamin Grinstein

Electron, Discovery of
Isobel Falconer

Funding of Particle Physics
Wolfgang K. H. Panofsky

Electroweak Phase Transition
Peter Arnold

Electroweak Symmetry Breaking
R. Sekhar Chivukula
Elizabeth H. Simmons

G

Energy
William E. Evenson

Gauge Theory
Vernon Barger
Charles Goebel

Energy, Center-of-Mass
William E. Evenson

Energy, Rest

Grand Unification
Vernon Barger
Graham Kribs

William E. Evenson

Experiment: Discovery of the Tau Neutrino
Byron G. Lundberg
Regina Rameika

Experiment: Discovery of the Top Quark
Meenakshi Narain

Ϫ
Experiment: gϪ2 Measurement of
the Muon
B. Lee Roberts

Experiment: Search for the Higgs Boson
David Rainwater

BUILDING BLOCKS OF MATTER

H

Hadron, Heavy
Adam F. Falk

Higgs Phenomenon
Christopher T. Hill

xix


LIST OF ARTICLES

Hubble Constant

Lawrence, Ernest Orlando

Wendy L. Freedman

Gordon J. Aubrecht II

Lepton
Janet Conrad

I
Inflation

M

Neil G. Turok

Influence on Science

David H. Saxon

Injector System
Donald Hartill

International Nature of Particle Physics
Maurice Jacob

J

Metaphysics
John Polkinghorne

Momentum
Lawrence A. Coleman

Muon, Discovery of
Robert H. March

N

J/␺
Helen Quinn

Japanese High-Energy Accelerator Research
Organization, KEK

Neutrino
Chung W. Kim

Neutrino Oscillations
Francis Halzen
M.C. Gonzalez-Garcia

Kazuo Abe

Jets and Fragmentation
George Sterman

Neutrino, Discovery of
Laurie M. Brown

Neutrino, Solar
Wick C. Haxton

Neutron, Discovery of

K

Roger H. Stuewer

Kendall, Henry

Noether, Emmy
Nina Byers

Lee Grodzins

O

L
Lattice Gauge Theory
G. Peter Lepage

xx

Outlook
Bruce Winstein

BUILDING BLOCKS OF MATTER


LIST OF ARTICLES

P

Quarks, Discovery of
Harry J. Lipkin

Parity, Nonconservation of
Lewis Ryder

Particle
Michael Dine

Particle Identification
David H. Saxon

Particle Physics, Elementary
Kenneth J. Heller

Pauli, Wolfgang
Laurie M. Brown

Phase Transitions
Marcelo Gleiser

Philosophy and Particle Physics
Michael L. G. Redhead

Planck Scale

R
Radiation, Cherenkov
Blair N. Ratcliff

Radiation, Synchrotron
Katharina Baur

Radioactivity
Benjamin Bayman

Radioactivity, Discovery of
Lawrence Badash

Reines, Frederick
Robert G. Arns

Relativity

Jonathan Bagger

Positron, Discovery of

Richard H. Price

Renormalization

Xavier Roqué

John F. Donoghue

Resonances
Gabor Domokos

Rutherford, Ernest

Q

Lawrence Badash

Quantum Chromodynamics
George Sterman

Quantum Electrodynamics

S

William J. Marciano

Quantum Field Theory
Ramamurti Shankar

Quantum Mechanics
Daniel F. Styer

Quantum Statistics
Frank Wilczek

Quantum Tunneling
Lawrence A. Coleman

Quark-Gluon Plasma
Krishna Rajagopal

Quarks
Alvin V. Tollestrup

BUILDING BLOCKS OF MATTER

Salam, Abdus
T. W. B. Kibble

Scattering
JoAnne Hewett

Schwinger, Julian
Silvan S. Schweber

SLAC (Stanford Linear Accelerator Center)

Helen Quinn

SSC
Edmund J. N. Wilson

Standard Model
Sally Dawson

xxi


LIST OF ARTICLES

String Theory

V

Joseph Polchinski

SU(3)
Elizabeth Jenkins

Virtual Processes
Robert Garisto
Rashmi Ray

Supernovae
Robert P. Kirshner

Supersymmetry

Jonathan L. Feng

Symmetry Principles
Michael Dine

W, X
Wigner, Eugene
Erich Vogt

T

Wilson, Robert R.
Albert Silverman
Boyce D. McDaniel

Technicolor
John Terning

Wu, Chien-Shiung
Noemie Benczer Koller

Thomas Jefferson National Accelerator
Facility
Lawrence S. Cardman

Thomson, Joseph John
Isobel Falconer

Y

Tomonaga, Sin-itiro
Laurie M. Brown

Yukawa, Hideki
Laurie M. Brown

U
Unified Theories

Z

David Gross

Universe
Terry P. Walker

xxii

Z Factory
Nan Phinney

BUILDING BLOCKS OF MATTER


LIST OF CONTRIBUTORS

Kazuo Abe
Japanese High-Energy Accelerator Research
Organization
Japanese High-Energy Accelerator

Research Organization, KEK
Peter Arnold
University of Virginia, Charlottesville
Electroweak Phase Transition
Robert G. Arns
University of Vermont, Burlington
Reines, Frederick
Neil Ashby
University of Colorado, Boulder
Case Study: Gravitational Wave Detection,
LIGO
Gordon J. Aubrecht II
Ohio State University
Lawrence, Ernest Orlando
Lawrence Badash
University of California, Santa Barbara
Radioactivity, Discovery of
Rutherford, Ernest
Jonathan Bagger
Johns Hopkins University
Planck Scale

Vernon Barger
University of Wisconsin, Madison
Gauge Theory
Grand Unification
William A. Barletta
Lawrence Berkeley National Laboratory
Devices, Accelerating
Katharina Baur

Stanford Synchrotron Radiation Laboratory
Radiation, Synchrotron
Benjamin Bayman
University of Minnesota, Minneapolis
Cyclotron
Radioactivity
Karl Berkelman
Cornell University
Cornell Laboratory for Elementary Particle
Physics
William K. Brooks Jr.
Thomas Jefferson National Accelerator Facility
Accelerators, Fixed-Target: Electron
Laurie M. Brown
Northwestern University
Neutrino, Discovery of
Pauli, Wolfgang
Tomonaga, Sin-itiro
Yukawa, Hideki

xxiii


LIST OF CONTRIBUTORS

Nina Byers
University of California, Los Angeles
Noether, Emmy
Lawrence S. Cardman
Thomas Jefferson National Accelerator Facility and

University of Virginia
Thomas Jefferson National Accelerator
Facility
R. Sekhar Chivukula
Boston University
Electroweak Symmetry Breaking
Lawrence A. Coleman
University of Arkansas at Little Rock
Momentum
Quantum Tunneling

William E. Evenson
Brigham Young University
Energy
Energy, Center-of-Mass
Energy, Rest
Isobel Falconer
Open University, UK
Electron, Discovery of
Thomson, Joseph John
Adam F. Falk
Johns Hopkins University
Hadron, Heavy
Jonathan L. Feng
University of California, Irvine
Supersymmetry

Janet Conrad
Columbia University
Lepton

Kenneth W. Ford
American Institute of Physics (retired)
Conservation Laws

Robert P. Crease
State University of New York, Stony Brook
Brookhaven National Laboratory

Gordon Fraser
Accelerators, Colliding Beams: Hadron

Sally Dawson
Brookhaven National Laboratory
Boson, Gauge
Standard Model
Michael Dine
University of California, Santa Cruz
Particle
Symmetry Principles

Wendy L. Freedman
Carnegie Observatories, Pasadena, CA
Hubble Constant
Robert Garisto
Physical Review Letters
Virtual Processes
Marcelo Gleiser
Dartmouth College
Phase Transitions

Gabor Domokos
Johns Hopkins University
Resonances

Charles Goebel
University of Wisconsin, Madison
Gauge Theory

John F. Donoghue
University of Massachusetts, Amherst
Broken Symmetry
Renormalization

M.C. Gonzalez-Garcia
European Laboratory for Particle Physics (CERN)
Neutrino Oscillations

Gerald F. Dugan
Cornell University
Accelerator

Howard A. Gordon
Brookhaven National Laboratory
Case Study: LHC Collider Detectors,
ATLAS and CMS

Guy T. Emery
Bowdoin College
Atom

Paul Grannis
State University of New York, Stony Brook
Detectors and Subsystems

xxiv

BUILDING BLOCKS OF MATTER


LIST OF CONTRIBUTORS

Benjamin Grinstein
University of California, San Diego
Flavor Symmetry
Lee Grodzins
Massachusetts Institute of Technology
Kendall, Henry
David Gross
University of California, Santa Barbara
Unified Theories
Howard E. Haber
University of California, Santa Cruz
Boson, Higgs
Francis Halzen
University of Wisconsin, Madison
Neutrino Oscillations
Frederick A. Harris
University of Hawaii, Honolulu
Beijing Accelerator Laboratory

Donald Hartill
Cornell University
Injector System
Wick C. Haxton
University of Washington, Seattle
Neutrino, Solar
Kenneth J. Heller
University of Minnesota, Minneapolis
Particle Physics, Elementary
JoAnne Hewett
Stanford Linear Accelerator Center
CKM Matrix
Scattering
Christopher T. Hill
Fermi National Accelerator Laboratory
Higgs Phenomenon

Maurice Jacob
European Laboratory for Particle Physics (CERN)
CERN (European Laboratory for Particle
Physics)
International Nature of Particle Physics
Michel Janssen
University of Minnesota, Minneapolis
Einstein, Albert
Elizabeth Jenkins
University of California, San Diego
SU(3)
T. W. B. Kibble
Imperial College, London

Salam, Abdus
Chung W. Kim
Johns Hopkins University and Korea Institute for
Advanced Study, Seoul, Korea
Neutrino
Robert P. Kirshner
Harvard-Smithsonian Center for Astrophysics,
Cambridge, MA
Supernovae
Adrienne W. Kolb
Fermi National Accelerator Laboratory
Fermilab
Noemie Benczer Koller
Rutgers University
Wu, Chien-Shiung
Helge Kragh
University of Aarhus, Denmark
Cosmology
Dirac, Paul
Lawrence M. Krauss
Case Western Reserve University
Cosmological Constant and Dark Energy
Graham Kribs
University of Wisconsin, Madison
Grand Unification

David Hitlin
California Institute of Technology
Detectors, Collider

G. Peter Lepage
Cornell University
Lattice Gauge Theory

L. Donald Isenhower
Abilene Christian University
Detectors, Particle

Harry J. Lipkin
Weismann Institute of Science, Rehovot, Israel
Quarks, Discovery of

BUILDING BLOCKS OF MATTER

xxv


LIST OF CONTRIBUTORS

Raphael Littauer
Cornell University
Accelerators, Colliding Beams: ElectronPositron
Byron G. Lundberg
Fermi National Accelerator Laboratory
Experiment: Discovery of the Tau
Neutrino
Robert H. March
University of Wisconsin, Madison
Muon, Discovery of
William J. Marciano

Brookhaven National Laboratory
Quantum Electrodynamics
John Marriner
Fermi National Accelerator Laboratory
Accelerators, Fixed-Target: Proton
Cooling, Particle
Extraction Systems

Elizabeth Paris
Massachusetts Institute of Technology
Antiproton, Discovery of
Roberto Peccei
University of California, Los Angeles
Basic Interactions and Fundamental Forces
Nan Phinney
Stanford Linear Accelerator Center
Z Factory
William H. Pickering
California Institute of Technology (emeritus)
Anderson, Carl D.
Joseph Polchinski
University of California, Santa Barbara
String Theory
John Polkinghorne
Queens College, Cambridge, UK
Culture and Particle Physics
Metaphysics

Boyce D. McDaniel
Cornell University

Wilson, Robert R.

Stephen Pordes
Fermi National Accelerator Laboratory
Detectors

Kevin McFarland
University of Rochester
Detectors, Fixed-Target

Richard H. Price
University of Utah, Salt Lake City
Relativity

Stephen G. Naculich
Bowdoin College
Cosmic Strings, Domain Walls

Helen Quinn
Stanford Linear Accelerator Center
J/␺
SLAC (Stanford Linear Accelerator
Center)

Meenakshi Narain
Boston University
Experiment: Discovery of the Top Quark
Dwight E. Neuenschwander
Southern Nazarene University
Antimatter

Keith Olive
University of Minnesota, Minneapolis
Dark Matter

David Rainwater
Fermi National Accelerator Laboratory
Experiment: Search for the Higgs Boson
Krishna Rajagopal
Massachusetts Institute of Technology
Quark-Gluon Plasma

Mark J. Oreglia
University of Chicago
Charmonium

Regina Rameika
Fermi National Accelerator Laboratory
Experiment: Discovery of the Tau
Neutrino

Wolfgang K. H. Panofsky
Stanford University
Funding of Particle Physics

Pierre Ramond
University of Florida, Gainesville
Family

xxvi

BUILDING BLOCKS OF MATTER