Nobel Laureates and Twentieth-Century Physics

by Mauro Dardo

Overview

Using an original approach, Mauro Dardo recounts the major achievements of twentieth-century physics—including relativity, quantum mechanics, atomic and nuclear physics, the invention of the transistor and the laser, superconductivity, binary pulsars, and the Bose-Einstein condensate—as each emerged. His year-by-year chronicle, biographies and revealing personal anecdotes help bring to life the main events since the first Nobel Prize was awarded in 1901. The work of the most famous physicists of the twentieth century—including the Curies, Bohr, Heisenberg, Einstein, Fermi, Feynman, Gell-Mann, Rutherford, and Schrödinger—is presented, often in the words and imagery of the prize-winners themselves. Mauro Dardo is Professor of Experimental Physics at Amedeo Avogadro University. He has served as Dean of the new Faculty of Sciences at the University of Turin in Alessandria, Piedmont, and has also served as Director of the university's new department of Sciences and Advanced Technologies.

Product Details

ISBN-13:	9780521540087
Publisher:	Cambridge University Press
Publication date:	10/14/2004
Edition description:	New Edition
Pages:	546
Product dimensions:	7.48(w) x 9.72(h) x 1.10(d)

Read an Excerpt

Cambridge University Press
0521832470 - Nobel Laureates and Twentieth-Century Physics - by Mauro Dardo
Excerpt

Part I
Introduction

Chapter 1
Introduction

The Nobel Prize awards entered upon their second century of life on 10 December of the year 2001. The event was celebrated in Stockholm, and in Oslo for the peace prize, with due pomp and circumstance when that year's prizewinners received their diplomas and medals in the presence of the Kings of Sweden and Norway, and of 200 past laureates who had been invited from all four corners of the earth to attend the ceremonies. The grandeur of the celebrations went to confirm what is universally agreed - that these prizes are considered everywhere to be the most prestigious honours of our times, far outstripping, indeed, all others.

The aim of the prizes is to reward outstanding contributions in the sciences of physics, chemistry, and physiology or medicine, as well as in literature and for peace. They were created by the Swedish inventor and industrialist Alfred Nobel, who decided to set up a special fund in his will for this purpose. The first awards were conferred on 10 December 1901, on the fifth anniversary of Nobel's death. Thereafter, the ritual has always taken place on the same date. Since its beginning in 1901, and up to the year 2003, there have been 758 individuals and organisations who have received a Nobel Prize: 171 of these were for physics, 143 for chemistry, 180 for physiology or medicine, 100 for literature, 111 for peace and 53 for economic sciences (this last prize was set up in 1968 by the Bank of Sweden, to further honour the memory of Alfred Nobel). The prizes in 1901 were each worth 150 000 Swedish crowns (a current value of close to 900 000 US dollars). In 2003 each prize was worth 10 million Swedish crowns (nearly 1.3 million US dollars); and so it can still be considered one of the world's most valuable awards.

The Nobel Foundation is a private institution which administers the prizes and manages the finances of the fund. As instructed by Alfred Nobel in his will, the prizes for physics and chemistry are awarded by the Royal Swedish Academy of Sciences; the prize for physiology or medicine by the Caroline Institute of Medicine in Stockholm; the prize for literature by the Swedish Academy, also in Stockholm; and the peace prize by a five-person committee elected by the Norwegian parliament. Finally, it is the Swedish Academy of Sciences that awards the prize for economic sciences.

Alfred Bernhard Nobel (1833-96) was born in Stockholm, the son of an inventor and industrialist. In the early 1860s he built a small factory to manufacture nitro-glycerine, a powerful explosive then recently discovered; and a few years later he invented a method of mixing nitro-glycerine with an organic material, so reducing its volatility. The new explosive, named dynamite, was soon used in the building of roads, canals, railways and tunnels through mountains.

Nobel then built a network of factories throughout Europe. At his death on 10 December 1896, in San Remo on the Italian Riviera, his business empire was made up of more than ninety factories, and included more than three hundred patents. In his will Nobel provided that most of his estate, estimated at over 31 million Swedish crowns (with a current value of nearly 180 million US dollars), be set up as a fund to establish the five original annual prizes.

Fig. 1.1. Alfred Nobel. (Portrait by E. Österman, © The Nobel Foundation, Stockholm.)

The prize for physics

The decision-making process for evaluating proposals, and for the final selection for the prize in physics, is in outline as follows. Invitations to nominate candidates are sent out by a Committee, whose five members are elected by the Swedish Academy of Sciences. Those who are invited to submit nominations are scientists who have already been awarded the Nobel Prize, members of academies and professors of physics from foreign universities. The Committee looks for suitable candidates and proposes one of them to the Academy. This proposal is then voted on, initially by its Physics Section. Lastly, the final decision is taken by the Academy in a plenary session.

And now for the prizewinners themselves, and a word on their places of origin. The very first Nobel Prize for physics went to the German physicist Wilhelm Röntgen for his discovery of X-rays. Since then the Royal Academy has awarded ninety-seven prizes (for six years they were not awarded) to 171 scientists (among them, only two women: Marie Curie in 1903, and Maria Goeppert Mayer in 1963). The work for which the prizes were awarded was mainly carried out at universities, but also at national and international research centres, and industrial laboratories: these institutions belonged to fourteen different countries in all.

The USA rose to prominence in the second half of the twentieth century; of the forty-four prizes bestowed on it, thirty-six are post-1950 (seventy-seven laureates, among whom eight before 1950). The United Kingdom follows with twenty-two laureates, Germany with nineteen, France with twelve; Russia has ten laureates; Holland eight; Switzerland six; Sweden and Japan each have four laureates; while Denmark and Italy have both arrived at three. Finally, Austria, Canada, and India each have one laureate.¹

The Nobel Prize enhances the scientific prestige not only of nations, but also that of universities and research organisations. It is understood to be a measure of the performance of the institution responsible. In Europe, the University of Cambridge can boast fourteen out of the twenty-two prizewinners belonging to the UK; the Lebedev Institute of Physics in Moscow has six laureates; the Institute for Physical Problems in Moscow, the universities of Berlin, Leiden in Holland, Copenhagen in Denmark and the Sorbonne in Paris have three laureates each. In the USA the most honoured universities have been Columbia University with nine laureates and Harvard with seven. Next in order come Cornell, Stanford and the Massachusetts Institute of Technology (MIT) each with six; Berkeley and the University of Chicago with four laureates each; and finally, Princeton University, the University of Illinois at Urbana-Champaign and the California Institute of Technology (Caltech), each with three laureates.²

The largest national and international laboratories, all established after the Second World War, have competed in the field of particle physics: in the United States, the Brookhaven National Laboratory (BNL) was honoured with four Nobel Prizes (seven laureates); the Stanford Linear Accelerator Center (SLAC) has had three prizes (five laureates); and the Lawrence Berkeley National Laboratory (LBNL) three prizes (four laureates). In Europe, CERN, the international laboratory for particle physics near Geneva, Switzerland, has had two prizes assigned to it, and three laureates. Finally, the National Institute of Standards and Technology (NIST) in the USA has been twice rewarded during recent years (with two prizewinners) for discoveries in the field of atomic physics.

Industrial laboratories have contributed strongly to the progress of modern physics: in the lead we find the Bell Telephone Laboratories (commonly known as Bell Labs), which constitute the research branch of the American company Lucent Technologies (formerly part of AT&T). Since 1937 it has been honoured with six Nobel Prizes for physics, bestowed on ten scientists. Next after it is the IBM Zurich Research Laboratory (Switzerland), with two prizes and four laureates.

And now, before retracing the paths taken by our Nobel laureates, we should spare a glance at where the roots of the science of physics are to be found. So let us go back a little in time and have a look at the masters of science of the past, those predecessors of our Nobelists. This will provide a necessary prologue to our chronicle of the events of the last hundred years, and our history of the Nobel awards and their place in the evolution of twentieth-century physics.

Chapter 2
Founding fathers

History tells us that science develops in a continuous and comparatively steady way. Nevertheless, certain periods are marked by dramatic discoveries or far-reaching new theoretical ideas. One of these crucial periods was the seventeenth century, when modern science was born.

The revolution began in the field of astronomy. In 1543 the Polish canon and astronomer Nicolaus Copernicus published his famous book entitled On the Revolutions of the Celestial Spheres. In it he replaced the old astronomical system of the Greek astronomer Claudius Ptolemy of Alexandria with a new one. Copernicus proposed that the sun, not the earth, is at the centre of the universe, and that all the planets (including the earth) revolve around the sun. Later, in the early 1600s, the German astronomer and mathematician Johannes Kepler perfected Copernicus' theory, and came up with three empirical laws regarding planetary motion. He based his findings on the work of the Danish astronomer Tycho Brahe, who had made careful observations on the positions of the planets in the sky. The theory of their circular motion was thus abandoned and replaced by Kepler's elliptical orbits.

The coup de grâce to the philosophy of nature that had been based on the teaching of the Greek philosopher Aristotle is associated with the name of a great Italian scientist - Galileo Galilei. His fame mostly rests on his having produced convincing evidence for the Copernican system of the Universe, and for having pioneered modern science through his studies on the motion of bodies.

The revolution initiated by Galileo was completed at the end of the seventeenth century in England by Isaac Newton, probably the greatest scientific intellect of all time. Using mathematical techniques that he himself had devised, Newton formulated his three famous laws of motion and the law of universal gravitation, and thereby managed to explain how objects move both on earth and in the heavens. This was the first synthesis in the history of science, and represented the culmination of the 'Scientific Revolution'. Such was Newton's physics that it became a model for the scientists of the following two centuries, and greatly influenced the whole course of science. In the eighteenth century physicists and mathematicians greatly developed Newton's work, and the first systematic studies of electrical and heat phenomena were undertaken.

Towards a new science

Galileo - he was the last great Italian to be called by this, his first name - was professor of mathematics at the University of the Venetian Republic, which was at Padua. Here, in the summer of 1609, he heard about a spyglass that a Dutch optician had invented. Working on the principles of this invention, he built a telescope, and pointed it toward the heavens. He saw satellites orbiting Jupiter, spots on the sun, and noted the phases of Venus. These observations confirmed the Copernican theory. He later presented convincing arguments for his discoveries in his book entitled Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, generally known more simply as Dialogue.

Although Galileo is widely remembered for his astronomical discoveries, it is in the field of mechanics that he made substantial contributions to our understanding of nature, for he laid the foundations for the science of motion, presented in his masterpiece, Discourses and Mathematical Demonstrations Concerning Two New Sciences, more frequently called Two New Sciences.

The science of motion

The scientific method is applied by all physicists in their attempts to understand how the natural world works, and it underlies the principles that guide all scientific research and experimentation. It can be summarised in the words of Richard Feynman (Nobelist in 1965): 'Observation, reason, and experiment make up what we call the scientific method'. Then physicists try 'to find the laws behind experiment', that is, the basic 'rules' that govern the phenomena of nature, and as Galileo argued, the language that these rules are written in is mathematics:

[Natural] Philosophy is written in this grand book, the universe, which stands continually open to our gaze; [but this book] cannot be understood unless one first learns to comprehend the language and read the letters in which it is composed. It is written in the language of mathematics, and its characters are triangles, circles, and other geometric figures without which it is humanly impossible to understand a single word of it.¹

A similar example of the scientific method was that adopted by Galileo himself in his studies on falling bodies. He was able to derive the laws of their motion, which he then proceeded to verify by experiments. These involved balls which he caused to roll down an inclined plane: so doing, he became the first to discover that all freely falling bodies, no matter what their mass, experience the same acceleration - provided that this happens at the same place near the earth's surface. Galileo is also given the credit for two basic principles of the science of motion. The first is the principle of relativity. In the Dialogue he wrote:

Shut yourself up with some friend in the main cabin below decks on some large ship, and have with you there some flies, butterflies, and other small flying animals . . . With the ship standing still, observe carefully how the little animals fly with equal speed to all sides of the cabin . . . When you have observed all these things carefully, . . . have the ship proceed with any speed you like, so long as the motion is uniform and not fluctuating this way and that. You will discover not the least change in all the effects named, nor could you tell from any of them whether the ship was moving or standing still.²

So, assuming that the ship glides smoothly along, without any brusque movements, the passengers will be unable to notice the forward motion of the ship (provided naturally, that they do not notice any apparent movement relative to their surroundings).

The second principle is the principle of inertia, which we may express as follows: if a body has nothing acting on it, its velocity remains the same; thus a body which is at rest remains at rest, and one that is moving uniformly and rectilinearly continues to move uniformly and rectilinearly. Galileo never stated this principle in its general form; it is implicit in his studies on motion, which he repeatedly referred to in his book, Two New Sciences. It was Isaac Newton who arrived at its definitive modern formulation.

Fig. 2.1. Galileo Galilei (1564-1642). (University of Rochester, courtesy AIP Emilio Segrè Visual Archives.)

Let Newton be!

Nature, and Nature's Laws lay hid in Night.
God said, Let Newton be! and All was Light.

Isaac Newton, the 'great synthesizer' (as the biographer Gale Christianson called him), further elaborated the principles of the science of motion that had been outlined by Galileo. He also formulated the law of universal gravitation, and made great discoveries in the science of optics. In April 1665, Newton received his bachelor's degree from the University of Cambridge, England. That summer the university had to close for two years due to the outbreak of plague. So he returned to his home in Woolsthorpe, Lincolnshire, and spent this period ('the prime of my age for invention') devoting himself to 'mathematics and [natural] philosophy more than at any time since'. His extraordinary genius developed, and he succeeded in devising new and ingenious theories. He presented his new mechanics in his immortal Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), or Principia as it is universally known, which appeared in 1687. His optical researches were published in 1704 in his second masterpiece, entitled Opticks.

The Principia

The [Principia] by Isaac Newton . . . is probably the most important single work ever published in the physical sciences.

(Stephen W. Hawking)³

Let us briefly look into this monument of human intellect, whilst we review some of the basic notions of the science of mechanics. In Book Ⅰ, following the preface, which provides a set of definitions (mass, momentum, inertia and force), Newton presents his famous 'scholium', in which he discusses the concepts of 'absolute time' and 'absolute space'.

Absolute time and space

I. Absolute, true, and mathematical time, in and of itself and of its own nature, without reference to anything external, flows uniformly and by another name is called duration. Relative, apparent, and common time is any sensible and external measure . . . of duration by means of motion; such a measure - for example, an hour, a day, a month, a year - is commonly used instead of true time.

II. Absolute space, of its own nature without reference to anything external, always remains homogeneous and immovable. Relative space is any movable measure or dimension of this absolute space . . . determined by our senses from the situation of the space with respect to bodies and is popularly used for immovable space . . .⁴

These concepts were not seriously challenged until the beginning of the twentieth century, when Albert Einstein's (Nobel 1921) revolutionary special theory of relativity (p. 51) rendered them obsolete, with the result that they were abandoned.

Following this discussion on the nature of time and space, Newton proceeds with the laws of motion, which form the starting point of every argument in classical mechanics.

---

© Cambridge University Press

Table of Contents

1. Introduction; 2. Founding fathers; 3. Highlights of classical physics; Part I. The Triumphs of Modern Physics (1901–50): 4. New foundations; 5. The quantum atom; 6. The golden years; 7. The thirties; 8. The nuclear age; Part II. New Frontiers (1951–2003): 9. Wave of inventions; 10. New vistas on the cosmos; 11. The small, the large - the complex; 12. Big physics - small physics; 13. New trends.

Editorial Reviews

"The book is illustrated profusely with classic photographs of the physicists, along with diagrams and graphs to explicate their ideas. An appendix lists the prizes in chronological order. There is a glossary of useful physical terms, references, a select bibliography, and a good index. Highly recommended." CHOICE

"This is a fine history of physics in the 20th century, and also serves as a high-quality primer for the concepts that underlie quantum mechanics and the standard model of particle physics. Dardo has put together a well-illustrated, well-researched and interesting story." The Leading Edge

From the Publisher