More praise for Einstein’s Clocks, Poincaré’s Maps
“This is how twentieth-century science really began—not just in abstractions but in machines; not just in Einstein’s brain but in coal mines and railway stations. Peter Galison’s book is engaging, original, and absolutely brilliant.”
—James Gleick, author of Chaos
“Part history, part science, part adventure, part biography, part meditation on the meaning of modernity, Dr. Galison’s story takes readers from the patent office to lonely telegraphers sitting in the rain in the Andes, from the coal mines of France to town councils in New England as it circles around the exploits of Einstein and his rival. . . . In Dr. Galison’s telling of science, the meters and wires and epoxy and solder come alive as characters, along with physicists, engineers, technicians and others in the armies of modern science. . . . Experts on relativity agree that Dr. Galison has unearthed fascinating material.”
—Dennis Overbye, New York Times
“Peter Galison provides a masterful and exciting account of the revolution in our understanding of time that occurred at the beginning of the twentieth century. Galison places Einstein and Poincaré at the crossroads of physics, philosophy, and technology where the problem of coordinating distant clocks played a crucial role in both the new physics and the new technology.”
—David Gross,
Director, Institute for Theoretical Physics,
University of California, Santa Barbara
“In what amounts to a stroke of genius, Peter Galison employs his unmatched ability to depict historical events on many levels and from many vantage points, as well as his unique combination of historical, scientific, and philosophical sophistication, to shed fresh light on the revolution in physics that we associate with the word
‘Relativity.’ This is simultaneously an indispensable book for the specialist, and a wonderful ‘read’ for anyone.”
—Hilary Putnam,
Cogan University Professor Emeritus, Harvard University
“Peter Galison manages to break through the noise and find a fresh, idiosyncratic take on the great man: Einstein the clock-watcher. . . . What is extraordinary about Einstein’s Clocks, Poincaré’s Maps is the colorful way Galison recreates a forgotten world in which science and politics were transformed by the seemingly simple desire to know what time it is.”
—Corey S. Powell, Newsday
“Peter Galison provides a unique and enlightening view on the origin of time as we know it in the modern age. . . . We very rarely see Galison’s sort of multilayered historical account of the momentous changes that do occur. . . . Einstein’s Clocks, Poincaré’s Maps is a treat . . . packed with an abundance of challenging philosophical thoughts and delightful historical connections, which are worth pondering at length. Scientists, historians and philosophers of science, and many nonspecialists will all find this book enlightening and enjoyable.”
—Hasok Chang, American Scientist
“With ease and authority, Galison cuts through the many layers of physics, technology and philosophy. Brilliant.”
—Barbara Fisher, Boston Sunday Globe
“An important addition to school and community library History of Science collections, Einstein’s Clocks and Poincaré’s Maps is an exciting, intriguing and enthusiastically recommended coverage.”
—Library Bookwatch
“Galison offers a highly engaging and insightful account of the intersection of science, technology, and social need that grounded new developments to relativity theory, time keeping, and map making. This superb essay in the history of science reveals a story in which physics, engineering, philosophy, colonialism, and commerce collided. Highly recommended.”
—T. Eastman, Choice
“A richly detailed account of the interplay of scientific and technical issues at the beginning of the modern era.”
—Kirkus Reviews
“By giving a fresh view . . . Galison’s enjoyable book stimulates us to reconsider the underlying questions of modern physics.”
—Peter Pesic, Times Literary Supplement
“Galison’s meticulously detailed reconstruction gives a satisfyingly complete account of the two men’s differences. This is perhaps the most sophisticated history of science ever attempted in a popular science book. [A] wonderfully knowledgeable and thoughtful portrait of what really mattered in the forging of a key aspect of the modern world.”
—Jon Turney, The Guardian
“[Galison’s] insistence that the real world not only intruded into what historians and scientists have commonly thought of as a theoretical and abstract breakthrough in physics, but that the real world could have been essential for the breakthrough, is [his] great contribution. He convincingly contends that the growing insight into time coordination . . . was the result of a continuous interplay between abstract thought and concrete application [and] offers a new model for interpreting other events in this history of science.”
—Marc Rothenberg, Salem Press
“[I]f you want to know something about what goes on at the highest levels of science . . . it is a terrific goad to mediation.”
—economicprincipals.com
ALSO BY PETER GALISON
How Experiments End
Image and Logic: A Material Culture of Microphysics
COEDITED VOLUMES:
Big Science: The Growth of Large-Scale Research
The Disunity of Science
Atmospheric Flight in the Twentieth Century
Science in Culture
Picturing Science, Producing Art
The Architecture of Science
Scientific Authorship: Credit and Intellectual Property in Science
For Sam and Sarah,
who have taught me the right use of time
CONTENTS
Acknowledgments
CHAPTER 1. SYNCHRONY
Einstein’s Times
A Critical Opalescence
Order of Argument
CHAPTER 2. COAL, CHAOS, AND CONVENTION
Coal
Chaos
Convention
CHAPTER 3. THE ELECTRIC WORLDMAP
Standards of Space and Time
Times, Trains, and Telegraphs
Marketing Time
Measuring Society
Time into Space
Battle over Neutrality
CHAPTER 4. POINCARÉ’S MAPS
Time, Reason, Nation
Decimalizing Time
Of Time and Maps
Mission to Quito
Etherial Time
A Triple Conjunction
CHAPTER 5. EINSTEIN’S CLOCKS
Materializing Time
Theory-Machines
Patent Truths
Clocks First
Radio Eiffel
CHAPTER 6. THE PLACE OF TIME
Without Mechanics
Two Modernisms
Looking Up, Looking Down
Notes
Bibliography
Index
ACKNOWLEDGMENTS
I have benefited enormously from discussions with many students and colleagues. It is a privilege to be able in particular to thank David Bloor, Graham Burnett, Jimena Canales, Debbie Coen, Olivier Darrigol, Lorraine Daston, Arnold Davidson, James Gleick, Michael Gordin, Daniel Goroff, Gerald Holton, Michael Janssen, Bruno Latour, Robert Proctor, Hilary Putnam, Juergen Renn, Simon Schaffer, Marga Vicedo, Scott Walter, and especially Caroline Jones, for their many thoughtful comments. Over the years it has been a pleasure to have learned as well from many discussions with Einstein scholars Martin Klein, Arthur Miller, and John Stachel. Though short in pages, the manuscript and p
icture preparation were long and certainly could not have been done without the help of research assistants Doug Campbell, Evi Chantz, Robert Macdougall, Susanne Pickert, Sam Lipoff, Katia Scifo, Hanna Shell, and Christine Zutz. Particular thanks go to my Norton editor, Angela von der Lippe, and my agent, Katinka Matson, for good ideas and much encouragement. Amy Johnson and Carol Rose offered many editorial improvements. Finally, I owe a great deal to the many archivists who graciously helped in my research—especially at the Observatoire de Paris, the Archives Nationales, the Archives de la Ville de Paris, the New York Public Library, the U.S. National Archives, the National Archives of Canada, the Bürgerbibliothek Bern, and the Stadtarchiv Bern.
Chapter 1
SYNCHRONY
TRUE TIME WOULD never be revealed by mere clocks—of this Newton was sure. Even a master clockmaker’s finest work would offer only pale reflections of the higher, absolute time that belonged not to our human world, but to the “sensorium of God.” Tides, planets, moons—everything in the Universe that moved or changed—did so, Newton believed, against the universal background of a single, constantly flowing river of time. In Einstein’s electrotechnical world, there was no place for such a “universally audible tick-tock” that we can call time, no way to define time meaningfully except in reference to a definite system of linked clocks. Time flows at different rates for one clock-system in motion with respect to another: two events simultaneous for a clock observer at rest are not simultaneous for one in motion. “Times” replace “time.” With that shock, the sure foundation of Newtonian physics cracked; Einstein knew it. Late in life, he interrupted his autobiographical notes to apostrophize Sir Isaac with intense intimacy, as if the intervening centuries had vanished; reflecting on the absolutes of space and time that his theory of relativity had shattered, Einstein wrote: “Newton, forgive me [‘Newton, verzeih’ mir’]; you found the only way which, in your age, was just about possible for a man of highest thought—and creative power.”1
At the heart of this radical upheaval in the conception of time lay an extraordinary yet easily stated idea that has remained dead-center in physics, philosophy, and technology ever since: To talk about time, about simultaneity at a distance, you have to synchronize your clocks. And if you want to synchronize two clocks, you have to start with one, flash a signal to the other, and adjust for the time that the flash takes to arrive. What could be simpler? Yet with this procedural definition of time, the last piece of the relativity puzzle fell into place, changing physics forever.
This book is about that clock-coordinating procedure. Simple as it seems, our subject, the coordination of clocks, is at once lofty abstraction and industrial concreteness. The materialization of simultaneity suffused a turn-of-the-century world very different from ours. It was a world where the highest reaches of theoretical physics stood hard by a fierce modern ambition to lay time-bearing cables over the whole of the planet to choreograph trains and complete maps. It was a world where engineers, philosophers, and physicists rubbed shoulders; where the mayor of New York City discoursed on the conventionality of time, where the Emperor of Brazil waited by the ocean’s edge for the telegraphic arrival of European time; and where two of the century’s leading scientists, Albert Einstein and Henri Poincaré, put simultaneity at the crossroads of physics, philosophy, and technology.
Einstein’s Times
For its enduring echoes, Einstein’s 1905 article on special relativity, “On the Electrodynamics of Moving Bodies,” became the best-known physics paper of the twentieth century, and his dismantling of absolute time is its crowning feature. Einstein’s argument, as usually understood, departs so radically from the older, “practical” world of classical mechanics that the paper has become a model of revolutionary thought, seen as fundamentally detached from a material, intuitive relation to the world. Part philosophy and part physics, Einstein’s rethinking of simultaneity has come to stand for the irresolvable break between modern physics and all earlier framings of time and space.
Einstein began his relativity paper with the claim that there was an asymmetry in the then-current interpretation of electrodynamics, an asymmetry not present in the phenomena of nature. Almost all physicists around 1905 accepted the idea that light waves—like water waves or sound waves—must be waves in something. In the case of light waves (or the oscillating electric and magnetic fields that constituted light), that something was the all-pervasive ether. Most late-nineteenth-century physicists considered the ether to be one of the great ideas of their era, and they hoped that once properly understood, intuited, and mathematized, the ether would lead science to a unified picture of phenomena from heat and light to magnetism and electricity. Yet it was the ether that gave rise to the asymmetry that Einstein rejected.2
In physicists’ usual interpretation, Einstein wrote, a moving magnet approaching a coil at rest in the ether produces a current indistinguishable from the current generated when a moving coil approaches a magnet at rest in the ether. But the ether itself could not be observed, so in Einstein’s view there was but a single observable phenomenon: coil and magnet approach, producing a current in the coil (as evidenced by the lighting of a lamp). But in its then-current interpretation, electrodynamics (the theory that included Maxwell’s equations—describing the behavior of electric and magnetic fields—and a force law that predicted how a charged particle would move in these fields) gave two different explanations of what was happening. Everything depended on whether the coil or the magnet was in motion with respect to the ether. If the coil moved and the magnet remained still in the ether, Maxwell’s equations indicated that the electricity in the coil experienced a force as the electricity traversed the magnetic field. That force drove the electricity around the coil lighting the lamp. If the magnet moved (and coil stayed still), the explanation changed. As the magnet approached the coil, the magnetic field near the coil grew stronger. This changing magnetic field (according to Maxwell’s equations) produced an electric field that drove the electricity around the stationary coil and lit the lamp. So the standard account gave two explanations depending on whether one viewed the scene from the point of view of the magnet or the point of view of the coil.
As Einstein reframed the problem there was one single phenomenon: coil and magnet approached each other, lighting the lamp. As far as he was concerned, one observable phenomenon demanded one explanation. Einstein’s goal was to produce that single account, one that did not refer to the ether at all, but instead depicted the two frames of reference, one moving with the coil and one with the magnet, as offering no more than two perspectives on the same phenomenon. At stake, according to Einstein, was a founding principle of physics: relativity.
Almost three hundred years earlier, Galileo had similarly questioned frames of reference. Picturing an observer in a closed ship’s cabin, borne smoothly across the seas, Galileo reasoned that no mechanical experiment conducted in a below-deck laboratory would reveal the motion of the ship: fish would swim in a bowl just as they would were the bowl back on land; drops would not deviate from their straight drip to the floor. There simply was no way to use any part of mechanics to tell whether a room was “really” at rest or “really” moving. This, Galileo insisted, was a basic feature of the mechanics of falling bodies that he had helped create.
Building on this traditional use of the relativity principle in mechanics, Einstein in his 1905 paper raised relativity to a principle, asserting that physical processes are independent of the uniformly moving frame of reference in which they take place. Einstein wanted the relativity principle to include not only the mechanics of drops dripping, balls bouncing, and springs springing but also the myriad effects of electricity, magnetism, and light.
This relativity postulate (“no way to tell which unaccelerated reference frame was ‘truly’ at rest”) gave rise to an additional assumption that proved even more surprising. Einstein noted that experiments did not show light traveling at any speed other than 300,000 kilometers per second. He t
hen postulated that this was always so. Light, Einstein said, always travels by us at the same measured speed—300,000 kilometers per second—no matter how fast the light source is traveling. This was certainly not how everyday objects behaved. A train approaches and the conductor throws a mailbag forward toward a station; it goes without saying that someone standing on the station platform sees the bag approach at the speed of the train plus the speed at which the conductor habitually hurls mail. Einstein insisted that light was different: stand, your lantern raised, at a fixed distance from me and I see the light travel by me at 300,000 kilometers per second. Hurtle toward me on a train, even one moving at 150,000 kilometers per second (half the speed of light), and I still see the light from your lantern go by me at 300,000 kilometers per second. According to Einstein’s second postulate, the speed of the source does not matter to the velocity of light.
Both of these postulates would have seemed reasonable (at least in part) to Einstein’s contemporaries. In the science of mechanics, not only had the principle of relativity been around since Galileo, but for some years Poincaré (among others) had also analyzed the relativity principle’s problems and prospects in electrodynamics.3 If light, moreover, was nothing but an excitation of waves in a rigid, all-pervasive ether, then in the frame of reference in which the ether was at rest, it was plausible to assume that the speed of light would not depend on the speed of the light source. After all, for reasonable source speeds, the speed of sound does not depend on the velocity of the source: once a sound wave is started, it moves through air at a fixed speed.
But how could Einstein’s two postulates be reconciled? Suppose in the ether rest frame a light was shining. To an observer moving with respect to the ether, wouldn’t the light appear to travel either faster or slower than normal, depending on whether the moving observer was approaching or retreating from the light? And if a difference in the velocity of light was observable, then wouldn’t that violate the principle of relativity, since that observation would indicate whether one was truly moving with respect to the ether? Yet no such difference could be measured. Even precise optical experiments failed to detect the slightest hint of motion through the ether.
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