Subject Grouping: Praxis

By Ivar Giaever
World Scientific

At the end of his last semester studying mechanical engineering at the Norwegian Institute of Technology, Ivar Giaever gained a grade of 3.5 for a thesis on the efficiency of refrigeration machines – just a little better than the 4.0 needed to pass. The thesis had been hastily written as the machines worked badly, and he and his friend had had little time to collect their data. But they both scraped through and, as Giaever writes, “maybe sometimes life is a little bit fair after all?”.

It’s a reference to the opening words of his light-hearted autobiography: “Life is not fair, and I, for one, am happy about that.” The title sounds provocative, but

the book is a reflection on how life’s little twists and turns can have extremely important consequences.

Giaever calls this “luck” and admits that he has had more than his share of it – from relatively humble beginnings in Norway to a Nobel prize and beyond.

In many respects Giaever had been a “bad” student. Good at cards, billiards, chess – and drinking – he had little interest in mechanical engineering. He finished with a grade of 4.0 in both physics and mathematics; but had at least married Inger, his long-time sweetheart.

His first job was at the patent office in Oslo, but apartments were hard to find, so the couple decided to emigrate to Canada. A few twists led Giaever to General Electric (GE), where he had the chance to study again through the company’s “A, B and C” courses.

This second chance to learn proved pivotal. Seeing how the studies related to GE’s production of generators, motors and such like, made learning exciting, and Giaever graduated as the best student on the A course. But GE in Canada offered only the A course and, eager to learn more, he moved to GE’s Research Laboratory in Schenectady in the US.

There he completed the B and C courses, and also began studying for a master’s degree in physics at the Rensselaer Polytechnic Institute (RPI). He was to remain with GE for the next 30 years, after being offered a permanent job, even though he did not yet have a PhD.

As a fully-fledged member of the research lab, Giaever needed a project. John Fisher proposed that he look into quantum mechanical tunnelling between thin films, which Giaever went on to do with great success in 1959.

Then, during his studies at RPI, he learned about the new Bardeen–Cooper–Schrieffer (BCS) theory of superconductivity, which predicted the appearance of a forbidden energy gap near the Fermi level when a metal becomes superconducting. Giaever realised that he could measure this gap using his tunnelling apparatus, and so provide crucial verification of the BCS theory. He also realised that tunnelling between two superconductors with different energy gaps would produce a negative resistance, and could allow for active devices such as amplifiers. He worried that if he talked about his work, others would realise this before he had done the relevant experiment.

To his surprise nobody did, hence his comment to his family: “I am the smartest man I know!”. His children thought he was being big-headed, but in 1973 the whole family went with him to Stockholm when he was rewarded with a share of the Nobel Prize in Physics in 1973 for his work on tunnelling in superconductors.

Giaever, of course, covers much more of his life story in this book. There is little technical detail, but a plethora of anecdotes that provide fascinating insight into a person who has made the most of his life.

Two impressions stand out: he is lucky to have found in Inger a partner with whom he has been able to share his long life; and he is lucky to have had a second chance to study and discover that he is smarter than many people thought.

By Nicholas Manton and Nicholas Mee
Oxford University Press

Ranging from classical to quantum mechanics, from nuclear to particle physics and cosmology, this book aims to provide an overview of various branches of physics in both a comprehensive and concise fashion. As the authors state, their objective is to offer an inspirational tour of fundamental physics that is accessible to readers with a high-school background in physics and mathematics, and to motivate them to delve deeper into the topics covered.

Key equations are presented and their solutions derived, ensuring that each step is clear. Emphasis is also placed on the use of variational principles in physics.

After introducing some basic ideas and tools in the first chapter, the book presents Newtonian dynamics and the application of Newton’s law of gravitation to the motion of bodies in the solar system. Chapter 3 deals with the electromagnetic field and Maxwell’s equations. From classical physics, the authors jump to Einstein’s revolutionary theory of special relativity and the concept of space–time. Chapters 5 and 6 are devoted to curved space, general relativity and its consequences, including the existence of black holes. The other revolutionary idea of the 20th century, quantum mechanics, is discussed in chapters 7 and 8, while chapter 9 applies this theory to the structure and properties of materials, and explains the fundamental principles of chemistry and solid-state physics. Chapter 10 covers thermodynamics, built on the concepts of temperature and entropy, and gives special attention to the analysis of black-body radiation. After an overview of nuclear physics (chapter 11), chapter 12 presents particle physics, including a short description of quantum field theory, the Standard Model with the Higgs mechanism and the recent discovery of its related boson. Chapters 13 and 14 are about astrophysics and cosmology, while the final chapter discusses some of the fundamental problems that remain open.

By Katherine Freese
Princeton University Press

Also available at the CERN bookshop

This book by Katherine Freese, now out in paperback, is aimed at non-professionals interested in dark matter. The hypothesis that the matter in galaxy clusters is dominated by a non-luminous component, and hence is dark, goes back to a paper published in 1933 by the Swiss astronomer Fritz Zwicky, who also coined the term “dark matter”. But it has only been during the last 20 years or so that we have realised that the matter in the universe is dominated by dark matter and that most of it is non-baryonic, i.e. not made of the stuff that makes up all the other matter we know.

The author explains the observational evidence for dark matter and its relevance for cosmology and particle physics, both in a formal scientific context and also based on her personal adventures as a researcher in this field. I especially enjoyed her detailed, well-informed discussion and evaluation of present dark-matter searches.

The book is structured in nine chapters. The first is a personal introduction, followed by a historical account of the growing evidence for dark matter. Chapter 3 discusses our present understanding of the expanding universe, explaining how much of what we know is due to the very accurate observations of the cosmic microwave background. This is followed by a chapter on Big Bang nucleosynthesis, describing how the first elements beyond hydrogen (deuterium, helium-3, lithium and especially helium-4) were formed in the early universe. In the fifth chapter, the plethora of dark-matter candidates – ranging from axions to WIMPS and primordial black holes – are presented. Chapter 6 is devoted to the LHC at CERN: its four experiments are briefly described and the discovery of the Higgs is recounted. Chapters 6 and 7 are at the heart of the author’s own research (the author is a dark-matter theorist and not heavily involved in any particular dark-matter experiments). They discuss the experiments that can be undertaken to detect dark matter, either directly or indirectly or via accelerator experiments. An insightful and impartial discussion of present experiments with tentative positive detections is presented in chapter 8. The final chapter is devoted to dark energy, responsible for the accelerated expansion of the universe. Is it a cosmological constant or vacuum energy with a value that is many orders of magnitude smaller than what we would expect from quantum field theory? Is it a dynamical field or does the beautiful theory of general relativity break down at very large distances?

Even though in some places inaccuracies have slipped in, most explanations are rigorous yet non-technical. In addition to the fascinating subject, the book contains a lot of interesting personal and historical remarks (many of them from the first- or second-hand experience of the author), which are presented in an enthusiastic and funny style. They are one of the characteristics that make this book not only an interesting source of information but also a very enjoyable read.

As a female scientist myself, I appreciated the way the author acknowledges the work of women in science. She presents a picture of a field of research that has been shaped by many brilliant female scientists, starting from Vera Rubin’s investigations of galaxy rotation curves and ending with Elena Aprile’s and Laura Baudis’ lead in the most advanced direct dark-matter searches. It seems to need a woman to do justice to our outstanding female colleagues.

The fact that less than three years after the first publication of the book some cosmological parameters have shifted and some information about recent experiments is already outdated only tells us that dark matter is a hot topic of very active research. I sincerely hope that the author’s gut feeling is correct and the discovery of dark matter is just around the corner.

By A G Wright
Oxford University Press

This volume is a comprehensive handbook aimed primarily at those who use, design or build vacuum photomultipliers. Drawing on his 40 years of experience as a user and manufacturer, the author wrote it to fill perceived gaps in the existing literature.

Photomultiplier tubes (PMTs) are extremely sensitive light detectors, which multiply the current produced by incident photons by up to 100 million times. Since their invention in the 1930s they have seen huge developments that have increased their performance significantly. PMTs have been and still are extensively applied in physics experiments and their evolution has been shaped by the requirements of the scientific community.

The first group of chapters sets the scene, introducing light-detection techniques and discussing in detail photocathodes – important components of PMTs – and optical interfaces. Since light generation and detection are statistical processes, detectors providing electron multiplication are also considered statistical in their operation. As a consequence, a chapter is dedicated to some theory of statistical processes, which is important to choose, use or design PMTs. The second part of the book deals with all of the important parameters that determine the performance of a PMT, each analysed thoroughly: gain, noise, background, collection and counting efficiency, dynamic range and timing. The effects of environmental conditions on performance are also discussed. The last part is devoted to instrumentation, in particular voltage dividers and electronics for PMTs.

Each chapter concludes with a summary and a comprehensive set of references. Three appendices provide additional useful information.

The book could become a valuable reference for researchers and engineers, and for students working with light sensors and, in particular, photomultipliers.

By Jennifer Coopersmith
Oxford University Press

With contagious enthusiasm and a sense of humour unusual in this kind of literature, this book by Jennifer Coopersmith deals with the principle of least action or, to be more rigorous, of stationary action. As the author states, this principle defines the tendency of any physical system to seek out the “flattest” region of “space” – with appropriate definitions of the concepts of flatness and space. This is certainly not among the best-known laws of nature, despite its ubiquity in physics and having survived the advent of several scientific revolutions, including special and general relativity and quantum mechanics. The author makes a convincing case for D’Alembert’s principle (as it is often called) as a more insightful and conceptually fertile basis to understand classical mechanics than Newton’s laws. As she points out, Newton and D’Alembert asked very different questions, and in many cases variational mechanics, inspired by the latter, is more natural and insightful than working in Newton’s absolute space, but it can also feel like using a sledgehammer to crack a peanut.

The book starts with a general and very accessible introduction to the principle of least action. Then follows a long and interesting description of the developments that led to the principle as we know it today. The second half of the book delves into Lagrangian and Hamiltonian mechanics, while the final chapter illustrates the relevance of the principle for modern (non-classical) physics, although this theme is also touched upon several times in the preceding chapters.

An important caveat is that this is not a textbook: it should be seen as complementary to, rather than a replacement for, a standard introduction to the topic. For example, the Euler–Lagrange equation is presented but not derived and, in general, mathematical formulae are kept to a bare minimum in the main text. Coopersmith compensates for this with several thorough appendices, which range from classical textbook-like examples to original derivations. She makes a convincing critique of a famous argument by Landau and Lifshitz to demonstrate the dependence of kinetic energy on the square of the speed, and in one of the appendices she develops an interesting alternative explanation.

Although the author pays a lot of credit to The Variational Principles of Mechanics by Cornelius Lanczos (written in 1949 and re-edited in 1970), hers is a very different kind of book aimed at a different public. Moreover, the author has developed several original and insightful analogies. For example, she remarks upon how smartphones know their orientation: instead of measuring positions and angles with respect to external (absolute) space, three accelerometers in the phone measure tiny motions in three directions of the local gravity field. This is reminiscent of the methods of variational mechanics.

Notations are coherent throughout the book and clearly explained, and footnotes are used wisely. With an unusual convention that is never made explicit, the author graphically warns the reader when a footnote is witty or humorous, or potentially perceived as far-fetched, by putting the text in parenthesis.

My main criticism concerns the frequent references to distant chapters, which entangle the logical flow. This is a book made for re-reading and, as a result, it might be difficult to follow for readers with little previous knowledge of the topic. Moreover, I was rather baffled by the author’s confession (repeated twice) that she was unable to find a quote by Feynman that she is sure to have read in his Lectures. Nevertheless, these minor flaws do not diminish my general appreciation for Coopersmith’s very useful and well-written book.

The first part is excellent reading for anybody with an interest in the history and philosophy of science. I also recommend the book to students in physics and mathematics who are willing to dig deeper into this subject after taking classes in analytical mechanics, and I believe that it is accessible to any student in STEM disciplines. Practitioners in physics from any sub-discipline will enjoy a refresh and a different point of view that puts their tools of the trade in a broader context.

By T W Donnelly, J A Formaggio, B R Holstein, R G Milner and B Surrow
Cambridge University Press

This textbook aims to present the foundations of both nuclear and particle physics in a single volume in a balanced way, and to highlight the interconnections between them. The material is organised from a “bottom-up” point of view, moving from the fundamental particles of the Standard Model to hadrons and finally to few- and many-body nuclei built from these hadronic constituents.

The first group of chapters introduces the symmetries of the Standard Model. The structure of the proton, neutron and nuclei in terms of fundamental quarks and gluons is then presented. A lot of space is devoted to the processes used experimentally to unravel the structure of hadrons and to probe quantum chromodynamics, with particular focus on lepton scattering. Following the treatment of two-nucleon systems and few-body nuclei, which have mass numbers below five, the authors discuss the properties of many-body nuclei, and also extend the treatment of lepton scattering to include the weak interactions of leptons with nucleons and nuclei. The last group of chapters is dedicated to relativistic heavy-ion physics and nuclear and particle astrophysics. A brief perspective on physics beyond the Standard Model is also provided.

The volume includes approximately 120 exercises and is completed by two appendices collecting values of important constants, useful equations and a brief summary of quantum theory.

By Gerard M Crawley and Eoin O’Sullivan
Imperial College Press

This book is designed as a “how to” guide to writing grant proposals for competitive peer review. Nowadays researchers are often required to apply to funding agencies to secure a budget for their work, but being a good researcher does not necessarily imply being able to write a successful grant proposal. Typically, the additional skills and insights needed are learnt through experience.

This timely book aims to guide researchers through the whole process, from conceiving the initial research idea, defining a project and drafting a proposal, through to the review process and responding to reviewers’ comments. Drawing on their own experience as reviewers in a number of different countries, the authors provide many important tips to help researchers communicate both the quality of their research and their ability to carry it out and manage a grant. The authors illustrate their guidelines with the help of many examples of both successful and unsuccessful grant applications, and emphasise key messages with quotes from reviewers.

The book also contains valuable advice for primary investigators on how to set up their research budget, manage people and lead their project. Two appendices at the end of the volume provide website addresses and references, as well as an outline of how to organise a grant competition.

Aimed primarily at early career researchers applying for their first grant, the book will also be beneficial to more experienced scientists, to the administrators of universities and institutions that support their researchers during the submission process, and to the staff of recently established funding organisations, who may have little experience in organising peer-review competitions.

By C Wendell Horton Jr and Sadruddin Benkadda
World Scientific

This 235 page book is dedicated to the ITER tokamak, the deuterium–tritium fusion reactor under construction in France, which aims to investigate the feasibility of fusion power. The book provides a concise overview of the state-of-the-art plasma physics involved in nuclear-fusion processes. Definitely not an introductory book – not even for a plasma-physics graduate student – it would be useful as a reference text for experts. Across 10 chapters, the authors describe the physics learned from previous tokamak projects around the world and the application of that experience to ITER.

After an introduction to the ITER project, the conventional magneto-hydrodynamic description of plasma physics is discussed, with strong emphasis on the geometry of the divertor (located at the bottom of the vacuum vessel to extract heat and reduce contamination of the plasma from impurities). Chapter 3 deals with the problem of alpha-particle distribution, which is a source of Alfven and cyclotron instabilities. Edge localised mode (ELM) instabilities associated with the divertor’s magnetic separatrix are also discussed. Conditions of turbulent transport are assumed throughout, so chapter 4 provides a general review of our (mainly experimental) knowledge of the topic. Chapters 5 and 6 are specific to the ITER design because they describe the ELM instabilities in the ITER tokamak and the solutions adopted for their control. Concluding the part dedicated to the fusion-reactor transient phase, steady-state operations and plasma diagnostics techniques are described in chapters 7 and 8, respectively.

The tokamak’s complex magnetic field is able to confine charged particles in the fusion plasma but not neutral particles. Neutron bombardment of surfaces can be viewed as an inconvenience, making it necessary to ensure the walls are radiation hard, or an advantage, turning the surfaces into a breeding blanket to generate further tritium fuel. Radiation hardness of the tokamak walls is discussed in chapter 9, while chapter 10 explains how ITER will transmute a lithium blanket into tritium via bombardment with fusion neutrons. The IFMIF (International Fusion Materials Irradiation Facility) project, conceived for fusion-material tests and still in its final design phase, is also briefly presented. The book closes with some predictions about the expectations to be fulfilled by ITER, before proceeding to the design of DEMO – a future tokamak for electrical-energy production.

In summary, ITER Physics is a book for expert scientists who are looking for a compact overview of the latest advances in tokamak physics. I appreciated the exhaustive set of references at the end of each chapter, since it provides a way to go deeper into concepts not exhaustively explained in the book. Plasma-fusion physics is complex, not only because it is a many-body problem but also because our knowledge in this field is limited, as the authors stress. I would have appreciated more graphic material in some parts: in order to fully understand how a fusion reactor works, one has to think in 3D, so schematics are always helpful.

By Gregory V Vereshchagin and Alexey G Aksenov
Cambridge University Press

This book provides an overview of relativistic kinetic theory, from its theoretical foundations to its applications, passing through the various numerical methods used when analytical solutions of complex equations cannot be obtained.

Kinematic theory (KT) was born in the 19th century and aims to derive the properties of macroscopic matter from the properties of its constituent microscopic particles. The formulation of KT within special relativity was completed in the 1960s.

Relativistic KT has traditional applications in astrophysics and cosmology, two fields that tend to rely on observations rather than experiments. But it is now becoming more accessible to direct tests due to recent progress in ultra-intense lasers and inertial fusion, generating growing interest in KT in recent years.

The book has three parts. The first deals with the fundamental equations and methods of the theory, starting with the evolution of the basic concept of KT from nonrelativistic to special and general relativistic frameworks. The second part gives an introduction to computational physics and describes the main numerical methods used in relativistic KT. In the third part, a range of applications of relativistic KT are presented, including wave dispersion and thermalisation of relativistic plasma, kinetics of self-gravitating systems, cosmological structure formation, and neutrino emission during gravitational collapse.

Written by two experts in the field, the book is intended for students who are already familiar with both special and general relativity and with quantum electrodynamics.

By Claus Grupen and Mark Rodgers
Springer International Publishing

Have you ever thought that batteries capable of providing energy over very long periods could be made with radioisotopes? Did you know that the bacterium deinococcus radiodurans can survive enormous radiation doses and, thanks to its ability to chemically alter highly radioactive waste, it could be potentially employed to clean up radioactively contaminated areas? And do you believe that cockroaches have an extremely high radiation tolerance? Apparently, the latter is a myth. These are a few of the curiosities contained in this “all that you always wanted to know about radioactivity” book from Grupen and Rodgers. It gives a comprehensive overview of the world of radioactivity and radiation, from its history to its risks for humans.

The book begins by laying the groundwork with essential, but quite detailed (similar to a school textbook), information about the structure of matter, how radiation is generated, how it interacts with matter and how it can be measured. In the following chapters, the book explores the substantial benefits of radioactivity through its many applications (not only positive, but also negative and sometimes questionable) and the possible risks associated with its use. The authors deal mainly with ionising radiation; however, in view of the public debate about other kinds of radiation (such as mobile-phone and microwave signals), they include a brief chapter on non-ionising radiation. Also interesting are the final sections, provided as appendices, which summarise the main technologies of radiation detectors as well as the fundamental principles of radiation protection. In the latter, the rationale behind current international rules and regulations, put in place to avoid excessive radiation exposure for radiation workers and the general public, is clearly explained.

This extensive topic is covered using easily understood terms and only elementary mathematics is employed to describe the essentials of complex nuclear-physics phenomena. This makes for pleasant reading intended for the general public interested in radioactivity and radiation, but also for science enthusiasts and inquisitive minds. As a bonus, the book is illustrated with eye-catching cartoons, most of them drawn by one of the authors.

The book emphasises that radiation is everywhere and that almost everything around us is radioactive to some degree: there is natural radioactivity in our homes, in the food that we eat and the air that we breathe. Radiation from the natural environment does not present a hazard; however, radiation levels higher than the naturally occurring background can be harmful to both people and the environment. These artificially increased radiation levels are mainly due to the nuclear industry and have therefore risen substantially since the beginning of the civil-nuclear age in the 1950s. This approach helps readers to put things in perspective and allows them to compare the numbers and specific measurement quantities that are used in the radiation-protection arena. These quantities are the same used by the media, for instance, to address the general public when a radiation incident occurs.

Not only will this book enrich the reader’s knowledge about radioactivity and radiation, it will also provide them with tools to better understand many of the related scientific issues. Such comprehension is crucial for anyone who is willing to develop their own point of view and be active in public debates on the topic.