bluuebunny/crossref_metadata_2025 huggingface dataset:
The Friction and Lubrication of Solids
Authors: Bowden F P , Tabor D
Published: November 2023

This classic work, originally published in 1950, was a landmark in the development of the subject of tribology. When it was first published, one reviewer wrote that it 'marks the beginning of a new epoch in the study of friction and lubrication .... The most interesting and comprehensive work on a single branch of physics I have ever read.' For the 1986 reprint David Tabor wrote a new preface, reviewing developments in the subject in the 36 years since the book first appeared. He has also added an appreciation of the life and work of F.P. Bowden, who died in 1968.
Area of Contact Between Solids
Authors: Bowden F P , Tabor D
Published: November 2023

It is a very difficult matter to prepare surfaces which are really flat. Even on carefully polished surfaces, hills and valleys are present which a.re large compared with the size of a, molecule. If two solids are placed in contact, the upper surface will be supported on the summits of the irregularities, and large areas of the surfaces will be separated by a, distance which is great compared with the molecular range of action. Although the techniques of grinding and polishing have advanced in the past few yea.re, it is still a difficult matter to prepare surfaces of appreciable size which are flat to within 100 to 1,000 A. Most of the surfaces used in engineering practice have surface irregularities which are very much greater than this. Since the range of molecular attraction is only a few Angstroms, we may expect that the area of intimate contact, that is, the area over which the surfaces are within molecular range, will, even for carefully prepared surfaces, be quite small.
Friction and Surface Damage of Sliding Metals
Authors: Bowden F P , Tabor D
Published: November 2023

Returning again to the sliding of metallic surfaces, there are, as we have seen, two major experimental observations. First that the area of contact .between them is very small so that the pressure at the local regions of contact is very high and is sufficient to cause plastic flow of the metal, and secondly that at sliding speeds frequently used in practice the surface temperatures may rise to very high values. The third point we need to investigate is the type of interaction· between the moving surfaces and the physical changes which occur in them during sliding.
Synopsis: course and control of migration of a typical long-distance migrant passerine
Authors: Berthold Peter
Published: November 2023

Current findings on various aspects of bird migration were presented in detail in the previous chapters. They paint a general picture of the course and control of movements of a typical migrant which is summarized in this chapter. For clarity, the conditions prevalent during the first outward migration of a typical long distance migrant are portrayed using, as an example, a Sylvia warbler migrating from western Central Europe to central and southern Africa.
The Heisenberg Hamiltonian
Authors: Aharoni Amikam
Published: November 2023

In the previous chapter we have always referred to the magnetization of the spin at the atomic lattice sites, which is just a manner of speaking. It is not very accurate for some ferromagnetic materials in which there is also a considerable contribution from the electron orbits.
Anisotropy and Time Effects
Authors: Aharoni Amikam
Published: November 2023

The Heisenberg Hamiltonian is completely isotropic, and its energy levels do not depend on the direction in space in which the crystal is magnetized. Throughout the previous chapters the measured magnetization was consistently denoted by Mz, where the z-direction is the direction of the applied field.
Another Energy Term
Authors: Aharoni Amikam
Published: November 2023

Besides the energy terms discussed so far, there is another term which has not been mentioned yet, and it is time to introduce it. This term is the magnetostatic self-energy which originates from the classical interactions among the dipoles.
The Nucleation Problem
Authors: Aharoni Amikam
Published: November 2023

It is very difficult to solve any non-linear differential equation, and it is even more difficult to choose the appropriate physical case among the various solutions which such an equation may have. Therefore, before trying any solution of Brown’s differential equations, it seemed desirable to define first the possible branch on which the required solution may be. For this purpose a solution was first sought of a set of linear differential equations, to be defined in section 9.1, which became known as the nucleation problem.
Numerical Micromagnetics
Authors: Aharoni Amikam
Published: November 2023

In all the numerical computations in micromagnetics, nearly all the computer time is spent on computing the magnetostatic energy term for the different magnetization configurations which are being tried. It must be emphasized that this feature is independent of the computational method, and is a result of the inevitable fact that the magnetostatic energy is defined by a six-fold integral, as explained in section 6.3, whereas all other energy terms involve only a three-fold integration.
Functional characteristics of eggs
Authors: Deeming D C
Published: November 2023

The egg is a key feature of avian reproductive biology and is theraison d’etre for the bird-nest incubation unit. As a consequence there has been a lot of interest in oology and egg composition and morphology have been extensively studied in a variety of species although, because it’s commercial significance, there has been a lot of emphasis on the eggs of the domestic fowl(Gallus gallus). This chapter only briefly reviews the morphology and composition of eggs from, where possible, non-commercial species; more extensive reviews of avian oology are provided by Romanoff and Romanoff (1949), Romanoff (1967) and Burley and Vadhera (1989). This chapter also describes the relationships between egg characteristics, embryonic development and various aspects of the incubation environment.
Parent-embryo interactions
Authors: Brua R B
Published: November 2023

During incubation, the embryo undergoes phenomenal transformations with specific senses developing in a well-defined progression. First, non-visual photic sensitivity appears followed by tactile, vestibular, proprioceptive, auditory, and finally, true visual capabilities develop (Gottlieb 1968). Eggs are also exposed to a variety of stimuli, including light, temperature changes, mechanical stimulation, and various auditory sounds. Thus, the ability of the embryo to react to certain stimuli is dependent on when the specific sensory system is functional. For example, an embryo is incapable of learning parental vocalisations if exposed to these stimuli prior to the development of the auditory sensory system. Lastly, the ability of an embryo to respond to certain stimuli may also be governed by its degree of maturity at hatching, i.e. altricial versus precocial.
Characteristics and constraints of incubation in hummingbirds
Authors: Calder III W A
Published: November 2023

Reproductive fitness is the crucial link by which lineages persist and evolve. The fundamentals of every field of study are manifested in this linkage: genetics, embryology, development, physiological regulation, and the behaviour of nest siting and construction, incubation, and acquisition and management of energy and food matter·all quantities of which are size-dependent. Hummingbirds (Order Apodiformes, Family Trochilidae) are some of the smallest birds and they lay some of the smallest eggs, in small clutches (Table 14.1). Mass-specific metabolic rates (kJ d-1 g-1 body mass), like egg mass g-1 body mass, are inversely proportional to body size and are most intense in the size range of hummingbirds ( Calder 1996; Brown and West 2000). In order to collect floral nectar, its main energy source, a hummingbird usually relies upon hovering flight which is energetically very expensive. In fact, when hovering, the rufous hummingbird(Selasphorus rufus) has the highest metabolic rate recorded for animals (Suarez 1992). In order to support this activity, the hummingbird needs a high daily nectar intake.
Adaptive significance of egg coloration
Authors: Underwood T J , Sealy S G
Published: November 2023

The extreme variability in the colours and patterns on birds’ eggs captured the attention of early naturalists and oologists. Poulton (18 90) suggested, in relation to eggs, ‘... any description of colour and marking will be considered incomplete unless supplemented by an account of their meaning and importance in the life of the species.’ Several hypotheses have been proposed to explain the adaptive significance of egg coloration. These include crypsis, egg recognition and mimicry, filtering solar radiation, eggshell strength, aposematism, and others. These hypotheses are reviewed for the adaptive significance of egg coloration as they relate to the variability in the ground colours and maculation of eggs. Except for immaculate blue and white eggs, and intraclutch variability, each hypothesis is discussed separately. Throughout the chapter, the following terminology is used. The ground colour of an egg shell is its uniform base colour, whereas maculation is the superficial markings or patterns (e.g. spots, scrawls, etc.) on top of the ground colour. Spots or spotting patterns describe a type of maculation composed of several round marks of various sizes. Pigmentation and coloration are general terms that refer collectively to the ground colour and maculation.
Back to Basics
Authors: Wark J S , Glazer A M
Published: November 2023

In any undergraduate physics course, students will meet a certain number of ‘core’ subjects with which any self-respecting physicist must become familiar. Of these, this book relates to three core disciplines.
The Statistics of Distinguishable Particles
Authors: Wark J S , Glazer A M
Published: November 2023

But we also know that the total number of particles is constant, and, as we defined the system as being isolated from the environment, so too is the energy.
Indistinguishable Particles and Monatomic Ideal Gases
Authors: Wark J S , Glazer A M
Published: November 2023

Up until this point we have been dealing with distinguishable particles. That is to say, we could tell which particle was which because they were localized within a solid. For instance, if one particle was in the ground state of a simple harmonic oscillator and a second was in the first excited state of another, we knew which was which (we could look and, for example, find the one in the ground state located at the corner of the crystal, and the excited one at some definite coordinate in the middle of the crystal).
Diatomic Ideal Gases
Authors: Wark J S , Glazer A M
Published: November 2023

Polyatomic molecules can rotate and vibrate, as well as have translational motion. The number of degrees of freedom a molecule possesses depends on the number of atoms within it. Here we consider the simplest case - diatomic molecules. The single-particle partition function that we have dealt with thus far has only taken into account the translational motion of the gas, and has not included these rotational and vibrational effects.
Quantum Statistics
Authors: Wark J S , Glazer A M
Published: November 2023

In Chapter 4 we learnt that in a gas of like particles we cannot distinguish one from another, and it is necessary to use the statistics of indistinguishable particles.
Electrons in Metals
Authors: Wark J S , Glazer A M
Published: November 2023

In this chapter we consider an example, in fact the best known example, of Fermi-Dirac statistics: an electron gas. Electrons have a spin of 1/2, and are thus fermions. Now surprisingly, a good approximation for the physics of the conduction electrons in a metal is to treat them as gas particles, ignoring the Coulomb force between them and their interactions with the ionic cores: this is known as the free electron model.
Bose-Einstein Condensation
Authors: Wark J S , Glazer A M
Published: November 2023

In Section 8.3 we studied blackbody radation that is a thermal distribution of photons, which we recall are bosons. However, we noted in that case that a collection of photons need not conserve particle number. We now turn to the question of the statistics of bosons when particle number is conserved.
The State and Future of Paleoepidemiology
Authors: Cohen Mark Nathan , Crane-Kramer Gillian
Published: November 2023

The study of prehistoric pathogens and the evolution of general health (Cohen 1989) calls attention to a long-term pattern of interaction between human behavior and pathogens which demonstrates the profound importance of human social and ecological change on disease organisms.
The molecular taphonomy of biological molecules and biomarkers of disease
Authors: Matheson C D , Brian D
Published: November 2023

Taphonomy is the study of the processes that affect biological material after death. Changes over time and how they alter the patterns of deposition, within the archaeological or palaeontological record, is the study of taphonomy (Reitz and Wing 1999). However, the broader use of this term now commonly refers to any post-mortem process that occurs, both biotic and abiotic. There are a number of taphonomic models (Davis 1987; Noe-Nygaard 1988) that all focus on the natural and anthropogenic factors leading to loss of information. This occurs firstly by natural alteration before, during, and after burial (first-order process); and secondly, during the excavation, sampling, storage, analysis, and presentation of the results (second-order process).
Twinning In Martensite
Authors: Bhattacharya Kaushik
Published: November 2023

In this chapter, we study a very important energy minimizing deformation – twins in the martensite. The purpose is two-fold. First, it gives a glimpse of the richness of the energy minimizing deformations in these martensitic materials. Second, it shows that the possible twinning modes in the martensite are determined as a consequence of the energy well structure. In other words, in this theory, one does not need to know the twinning modes a priori; instead, they are obtained as a result.
An overview of string theory and string models
Authors: Binétruy P
Published: November 2023

It is widely believed that string theory provides the consistent framework which lies behind low energy supersymmetry. The purpose of this chapter is to provide a non-technical overview of the main ideas of string theory1, as well as to present some of the new concepts which arise and which might lead to new developments in the study of the low energy theory. Due to lack of space, there is no room for doing justice to the richness of the complete string picture and we refer the reader to other monographs for a more thorough treatment e.g. [312]. However, string models are to be considered very seriously because they provide a complete picture of fundamental physics, including gravity. As such, they should be considered in their entirety because they have an internal coherence. Thus using them for low energy phenomenology (or cosmology) requires us at least to be aware of the general consistency of the string picture.
What is public health?
Authors: Walley John , Wright John , Hubley John
Published: November 2023

Imagine yourself as a health worker in a consultation room. In front of you is a sick person who has come to be treated. As a clinician you do everything you can to make that individual better. You have a similar attitude for the other patients sitting outside in the waiting room. You are committed to your job and are very busy every day treating those people that come for help. You give little thought to those people who haven’t come to the health facility— you assume that anyone who is really sick will visit you or other clinicians and so you are not concerned about those people who have not come to the clinic. In such a situation you would be taking an ‘individual case management’ approach to healthcare.
Managing and implementing interventions
Authors: Walley John , Wright John , Hubley John
Published: November 2023

Public health interventions will only have an impact on health if they are properly planned and managed. This chapter summarizes some of the main factors to be considered in the management of public health programmes (see Fig. 6.1).
Future trends in global public health
Authors: Walley John , Wright John , Hubley John
Published: November 2023

Much has been done to improve the health of populations throughout the world over the last century. Public health policies have provided healthier environments with clean water, effective sanitation, and better housing. Public health programmes have supported immunization campaigns to prevent diseases (such as tuberculosis, measles, diphtheria, pertussis, tetanus, and polio) and to provide preventative health services (such as maternal and child health services). Health promotion campaigns have attempted to improve awareness about the factors that cause disease and how they can be avoided, and to change individual risk-taking behaviour.
Introduction
Authors: Glyde Henry R
Published: November 2023

Quantum fluids and solids play a special role in condensed matter physics and materials science. The many body theory of Fermi and Bose systems was largely developed in the late 1950s and 1960s to describe liquid 3He and 4He at a microscopic level. The concepts of superfluidity in Bose and Fermi systems have been thoroughly explored in liquid 4He and 3He (cf. Lifshitz and Pitaevskii 1980; Vollhardt and Wölfle 1990). This understanding, hard won in quantum fluids, has found wide application across many fields and in more complex quantum systems. Solid helium is the most quantum solid readily available in nature. It displays highly anharmonic dynamics and serves as a prototype for more complex anharmonic solids. The self- consistent phonon theory also found its severest test in solid helium. For these reasons there is a vast literature and many books on this topic. A list of recent titles and conference proceedings appears at the end of this book.
Microscopic Picture
Authors: Glyde Henry R
Published: November 2023

In this chapter we outline the microscopic theory of an interacting Bose fluid. The aim is to provide a basis for a microscopic understanding of the excitations in superfluid and normal 4He discussed in the following chapters. The microscopic picture can be omitted on a first reading and referred to when desired.We assume that the reader is familiar with the theory of Bose-Einstein condensation in a Bose gas introduced in §7.2 and presented in many texts on statistical mechanics. In §7.2 we also discussed the generalization of Bose condensation to an interacting fluid by Penrose and Onsager (1956).Condensation was identified with macroscopic occupation of one of the eigenstates of the fluid and the appearance of an infinitely long tail in the one-body density matrix, denoted as off-diagonal long range order (ODLRO). For a homogeneous fluid it is natural to take momentum states as the eigenstates and to assume that the macroscopically occupied state is the state with momentum p = 0. In this case the criterion reduces to that for a gas but with a firm foundation.
Nature Of Excitations In Liquid 4He
Authors: Glyde Henry R
Published: November 2023

Our goal in this chapter is to summarize the theory and experiment set out in Chapters 7-11 with the aim of understanding the nature of excitations in superfluid and normal 4He. Is there an essential difference between the excitations in superfluid and normal 4He? Does the condensate play a clear role in the existence of a sharp excitation in super fluid 4 He at higher Q(Q≳ 1 Å−1) and do we need to have n  0(T) appearing explicitly in S(Q, ω) to explain the data? Can we learn from a comparison between liquid and solid 4He? We set out to answer these questions in this chapter.
The Impulse Approximation
Authors: Glyde Henry R
Published: November 2023

In the following three chapters we consider the response of helium at higher momentum transfer, Q ≳ 5 Å−1. At higher Q, helium responds like a collection of weakly interacting particles. In this chapter, we derive and discuss the impulse approximation (IA) to the dynamic structure factor, S(Q, ω). We will see that for systems in which the interatomic forces are not infinite anywhere, the IA holds at Q → ∞. In the IA, S(Q, ω) depends only on the momentum distribution, n(p), of the atom struck by the neutron.
Final State Contributions
Authors: Glyde Henry R
Published: November 2023

In the previous chapter we derived the impulse approximation (IA), to the dynamic structure factor given by (18.1). The corresponding intermediate structure factor is (18.8),where νiQ = (pi  Q)/mQ is the initial velocity of the struck atom along Q. The IA holds exactly in the limit Q → ∞ for particles interacting via a potential which is not infinitely steep anywhere (e.g. does not have a perfectly hard core). Since the helium interatomic potential is steeply repulsive but not infinite, we expect the IA to hold at Q → ∞ but not be reached until very high Q.
Concentrated ferromagnetic alloys
Authors: Hicks Trevor J
Published: November 2023

The analysis of defect scattering from concentrated ferromagnetic alloys is much more complicated than for dilute alloys. The effects of the defects now overlap so that they are no longer independent. There are a number of ways of dealing with this. Firstly, one can treat an alloy of one composition as a distribution of identical superposing defects. This is the early linear model of Marshall (1968). However, it is rarely the case that the defects do superpose in the sense that the addition of an extra impurity atom would add another identical defect. Normally the amplitude and extent of the defect in the moment distribution changes with composition. The defects obtained by this sort of analysis are thus an average for each particular composition. The linear model can be modified by including a correction to the effect of one impurity atom by the presence of a second (Balcar and Marshall 1968) but then the extension to triples and beyond becomes cumbersome. Some progress can be made by modelling the way in which the overlap of the effects of impurity atoms may be nonlinear. This is done in the magnetic environment model which is discussed in detail later in this chapter.
Amorphous magnets
Authors: Hicks Trevor J
Published: November 2023

Atomically glassy alloys are one further step away from regularity in materials. The magnetic systems which have been discussed are at least regular in the underlying lattice. The randomness has been restricted to the occupancy of the sites of the regular lattice. Amorphous materials have no regular lattice although it must be said that all practical amorphous materials show strong preferences for particular atomic distances. In terms of diffraction patterns this means that although there are no Bragg peaks the scattering is strongly structured.
Nonresonant inelastic X-ray scattering: Regime of core-electron excitation (X-ray Raman scattering)
Authors: Schülke Winfried
Published: November 2023

In Chapter 2 we utilized the basic relation between the double differential scattering cross-section and excitations in the scattering system, as given in equation (2.3) only by considering excitations of the valence electron systems of condensed matter. We will now examine inelastic scattering processes connected with excitations of core-electrons from closed shells into unoccupied states about which we want to learn by this type of spectroscopy. In this case we will speak, for more historical reasons, of non-resonant X-ray Raman scattering or spectroscopy, or still more briefly of X-ray Raman scattering or spectroscopy (XRS), if mixing up with resonant X-ray Raman scattering is not to be suspected.
Multilinear Mappings and Dual Spaces
Authors: Wasserman Robert H
Published: November 2023

We will discuss the important space, V*, of linear functions on a vector space, V. We will describe isomorphisms between spaces of multilinear mappings, and, finally, we will focus on special properties of bilinear functions.
Some Physics on Minkowski Spacetime
Authors: Wasserman Robert H
Published: November 2023

The mathematical steps in the above derivation are quite simple; basically, just the algebra of going from the Lorentz transformations to (21.2). It is the physical interpretation which is not so simple.
Quasicrystals
Authors: Janot C
Published: November 2023

In 1984 physicists discovered a monster in the world of crystallography, a structure that appeared to contain five-fold symmetry axes, which cannot exist in strictly periodic structures. Such quasi-periodic structures became known as quasicrystals. A previously formulated theory in terms of higher dimensional space groups was applied to them and new alloy phases were prepared which exhibited the properties expected from this model more closely. Thus many of the early controversies were dissolved. This primer provides a descriptive approach to the subject for those coming to it for the first time. The various practical, experimental, and theoretical topics are dealt with in an accessible style. The book is completed by problem sets and there is a computer program that generates a Penrose lattice.
High-dimensional crystallography
Authors: Janot C
Published: November 2023

As illustrated in Chapter 1, 3-dim quasiperiodic structures can be defined and constructed as 3-dim irrational cuts of objects which are periodically distributed in an n-dim space (n 〉 3). From the experimental point of view (cf. Chapter 2), a quasicrystal is simply an arrangement of atoms which, in diffraction experiments, produces infinitely sharp (δ-function) Bragg peaks in a pattern which exhibits over all ‘forbidden’ symmetry. These diffraction patterns must be treated as for regular 3-dim crystals in a systematic crystallographic description of the quasicrystals. As such, the crystallography of quasicrystals, or quasi crystallography for short, is simply high-dimensional crystallography with a generalization of the concept of space groups.
Where are the atoms?
Authors: Janot C
Published: November 2023

Now that we have discussed the existence of quasi periodicity and its representation by n-dim periodic structures, we must give practical examples of structure determination and try to understand how to think of the quasi crystal in our 3-dim world. We must repeat here the crucial difference between the description of a regular 3-dim crystal in terms of a unit cell plus an atomic basis and quasi crystals. In a regular crystal, one can always describe the structure as a stacking of ‘unit cells’, all of which are decorated with atoms in an identical manner. The quasi crystal can be envisioned in the same way, when described in its n-dim periodic aspect. That is, we associate a basis with each unit cell in n-dim, and repeat this motif for all cells.
Introduction
Authors: Binney J J , Dowrick N J , Fisher A J , Newman M E J
Published: November 2023

The phase transitions of H2O are matters of everyday experience: the boiling of water in a kettle; the formation of frost on clear winter nights; the melting of ice-cubes in a fizzy drink. Water turns into vapour, vapour into ice. ice into water. Life without the endless movement of H2O from one phase to another would be a sorry thing. Furthermore, since the earliest times the phase changes of substances other than H2O have been of the greatest technological (and therefore cultural and political) significance: the founding of metals to make swords, ploughshares and printer’s type; the evaporation and condensation of ammonia in refrigerators; the evaporation of petroleum distillates in carburettors—to name but a few that were important by the end of the nineteenth century. Phase transitions are central to life on Earth and understanding them is one of the prime tasks of condensed-matter physicists. This book seeks to contribute to that understanding by discussing a small but particularly interesting subset of all phase transitions, the ‘continuous’ ones.
Real-space renormalization
Authors: Binney J J , Dowrick N J , Fisher A J , Newman M E J
Published: November 2023

Until the early 1970s all calculations of critical exponents were made either by exactly solving a model for its thermodynamic properties and then examining its behaviour in the critical regime (as with the Ising model in one and two dimensions) or by direct numerical simulations (as with the three-dimensional Ising model) or by extrapolation from approximate solutions which become invalid in the vicinity of a phase transition (high-temperature expansions, for example). However, in a now-famous paper published in 1966, Kadanoff presented arguments which, he maintained, would allow one to simplify calculations in the critical regime to the point at which critical exponents could be extracted, without ever working out the partition function for the problem. However, though Kadanoff’s ideas showed great physical intuition about the processes giving rise to critical phenomena, they lacked the mathematical precision which might have given one faith in his results.
The Landau-Ginzburg model
Authors: Binney J J , Dowrick N J , Fisher A J , Newman M E J
Published: November 2023

Most of the rest of this book is devoted to study of the Landau-Ginzburg model. We devote so much space to this model because it is a kind of ‘metamodel’—it captures the essence of many of the models we have discussed, and elucidates how their behaviour near a critical point depends (i) on the dimensionality d of the underlying lattice, and (ii) on the dimensionality D of the order parameter. A toy such as the Landau-Ginzburg model that allows one to vary d and D with a minimum of fuss (and even make them non-integer!) reveals just how much phase transitions depend on D and d, and how little on the underlying lattice.
Renormalization
Authors: Binney J J , Dowrick N J , Fisher A J , Newman M E J
Published: November 2023

In Chapter 7 we introduced the Landau-Ginzburg ‘metamoder of phase transitions. The model’s partition function takes the form of a functional integral which cannot be done exactly. So in the last chapter we expressed this integral as an infinite series of functional integrals that can be reduced to ordinary multi-dimensional integrals. To keep track of these integrals we associated with each a Feynman diagram and used these diagrams to classify the integrals by the number of integrations or ‘loops’ each involves.
Physical properties of solids
Authors: White Guy K , Meeson Philip J
Published: November 2023

From earlier chapters we see that some properties of materials are particularly important in designing and making cryogenic equipment. Properties such as thermal conductivity (whether high or low), compatibility of thermal expansion with other materials, need for low magnetic susceptibility, mechanical strength and weight can be crucial. Whatever other data are required, we also need an estimate of heat capacity (and enthalpy) to calculate cooling requirements. In this chapter we discuss some of these properties and tabulate representative data (see Appendix B). The brief account of the underlying physics of each property should help the readers to understand and select materials and data appropriate to their needs, whether they be graduate students in physics, or engineers or biologists who have not done a course in solid state physics. For example, it is important to recognize when selecting copper wire for a heat link at low temperatures, that its effective conductivity at 10 K may differ by a factor of 1000 depending on the grade of copper.
Evolutionary ecology: natural selection in freshwater systems
Authors: Lampert Winfried
Published: November 2023

Evolutionary biology studies how organisms evolve on the molecular, genomic, and organismic level. It looks at the origin and maintenance of genetic variability, the mechanisms leading to changing gene frequencies by chance or selection, and the constraints inhibiting this process. Evolutionary ecology studies why organisms evolve. It identifies the biotic and abiotic environmental factors that drive natural selection. Textbooks view evolutionary ecology from two sides, either as an approach to general ecology (i.e. explaining ecology with evolutionary ideas) or as a subdiscipline of evolutionary biology (i.e. explaining evolution by the ecological framework).
Allopatric speciation: not so simple after all
Authors: Schilthuizen Menno , Scott Bronwen
Published: November 2023

Speciation, the evolutionary event in which one ancestral species splits into two or more daughter species, is a central subject in evolutionary biology. Despite this (or possibly because of this), the subject has been fraught with controversies, conflicts, and misunderstandings. To some extent, this unrest is the result of the difficulties of delineating what is meant by the term “species,” because, by definition, the species concept determines which events are considered crucial in speciation.
J. D. Bernal
Authors: Brown Andrew
Published: November 2023

J. D. Bernal, known as ‘Sage’, was an extraordinary man and multifaceted character. A scientist of dazzling intellectual ability and a leading figure in the development of X-ray crystallography, he was a polymath, a fervent Marxist, and much admired worldwide. Although he himself never won a Nobel Prize, several of his distinguished students went on to do so, including Dorothy Hodgkin, Max Perutz, and Aaron Klug. Andrew Brown has had unprecedented access to Bernal’s papers and diaries, and this biography includes previously unpublished material on Bernal’s role during the Second World War. Bernal not only changed the course of science, but was witness to (and often a participant in) historical events (the Easter Rebellion, the Great Strike, the anti-fascist movement and pacifist causes, civil defence, RAF bombing strategy, the planning for D-Day, post-war rebuilding, and nuclear weapons). One of the few men familiar with Downing Street, the White House and the Kremlin, he left fascinating accounts of Churchill, Stalin, Mao Zedong, Louis Mountbatten and Picasso, as well as the century’s greatest scientists. Brown’s compelling account covers all aspects of Bernal’s brilliant, colourful, and Bohemian life, and introduces this towering figure of early 20th century science to a wide audience.
A Long Way To Go
Authors: Brown Andrew
Published: November 2023

The newest and grandest liner in the White Star fleet, Celtic, sailed from Queenstown harbour without fanfare. She cut through the grey waves, rounding the Head of Kinsale as the late November sun slipped beneath the Atlantic Ocean. The coastline of southern Ireland became a faint black line, and the little boy who had been watching it intently turned to his mother and inquired, ‘Mammy, we will go back now?’ She replied, in French, ‘No, Desmond, they must go on to America, they won’t turn back now.’ ‘Not even for you, Mammy?’ Unlike most of the passengers, Elizabeth Bernal was not sailing away to seek a life in the New World. Her own mother, who was born into a land-owning Protestant family in County Antrim, had been taken to the United States as a child. She subsequently met and married a man in the small town of Knoxville, Illinois, but was soon widowed. The local Presbyterian minister, the Reverend William Young Miller, whose family came from New England, befriended her, and they married. Elizabeth (Bessie), one of their six children, was born in 1869. When her father retired from the ministry in 1883, he moved the family west to the new city of San Jose in California.
Bohemian Crystallographer
Authors: Brown Andrew
Published: November 2023

While his two-year effort to develop a quantitative analysis of the 230 space groups cost Bernal the first-class honours degree he coveted, the resulting thesis, ‘On the analytic theory of point group systems’, launched his career as a scientist. Without a first-class degree in physics, there was little prospect of being taken on as a research student in the Cavendish Laboratory, and even if Sage had managed to take a first, it is difficult to see how he would have satisfied Sir Ernest Rutherford’s edict that no communist propaganda would be tolerated in the laboratory. Nor would Bernal’s interest in the physics of crystals and his idea to use discoveries in that Weld as the keys to unlock the secrets of chemical structure have met with any degree of comprehension or sympathy in Rutherford’s department, where the major goal was to advance understanding about the atomic nucleus. In Rutherford’s robust view, scientific work aiming to establish the relative positions of atoms in space rather than to dissect the miniscule aggregation of electric charge and mass at each atom’s core would probably have been regarded as a branch of geography rather than physics.
The Shadow Of The Hawk’s Wings
Authors: Brown Andrew
Published: November 2023

About the time Hitler was grasping control of Germany in 1933, students in an Oxford Union debate passed what Churchill later described as ‘their ever-shameful resolution’ that ‘This House refuses in any circumstances to fight for King and Country.’ Yet those Oxford undergraduates were more in tune with the national mood than was Churchill, a brooding backbencher. Peace and national security were not seen by most as mutually exclusive goals, and there was no appetite for militarism in a country still trying to expunge the raw memories of the previous war. The Prime Minister himself was putting the final touches to ‘The MacDonald Plan’ to be presented to the Geneva Disarmament Conference. There was a widespread feeling, artfully exploited by the Nazi Party, that the Versailles Peace Treaty of 1919 had been unfair to the extent that it was now threatening the stability of Europe, and that the restitution of equal rights to Germany would enhance the prospects of security for all nations.
Rebuilding
Authors: Brown Andrew
Published: November 2023

Bernal’s wartime contact with Birkbeck College was slight and somewhat peevish. Breams Buildings had closed after being hit by incendiary bombs in September 1940, but reopened the following month, with lectures being given at weekends rather than in the evenings. Lewis Simons became acting head of the Physics Department, and in March 1941 word reached Sage that he had sacked Mr Reggie Dobb, the senior laboratory technician. Bernal immediately wrote a letter of protest, but the dismissal was upheld on the basis that staff numbers needed to be reduced. Sage then decided that since the College was in operation at weekends only, he should take up the reins again (this was at the time he was starting to work at Bomber Command). After several Faculty meetings, a compromise was reached whereby Mr Dobb would be re-employed, perhaps on a part time basis, when conditions improved. Eventually, he was rehired for four days per week, and Sage asked the College to pay him for a full week ‘to lay the last ghosts of a controversy’. H. Gordon Jackson, the Acting Master, complained to Sage, asking ‘Where is this to stop?’ Sage’s response was judged by the College administration to be ‘a complete travesty of the facts’.
Peace At Any Price?
Authors: Brown Andrew
Published: November 2023

The hunger for peace is most ravenous in the aftermath of war. The British public, many of whom could remember the First World War – the war to end all war – emerged from the Second World War weary from privations but thankful to have survived. Their suffering did not compare with that of the Poles or the Soviets or indeed the citizens of the two countries subjected to the most ferocious bombing campaigns – Germany and Japan. Modern warfare was no longer confined to the armed forces, and as one of the Chiefs of Staff remarked to Bernal, by the end of WW2, weapons determined strategy: strategy no longer dictated weapons. The new spectre of the atom bomb, as Bernal said at the time, ‘implicitly changed the whole existence of man in this universe’. While conceding that ‘the immediate effects, however horrible, have been decisive in ending the war’ Bernal suggested that ‘the possibilities of further destructive use are in every man’s mind’. Bernal had more reason than most to worry about such a catastrophe from his involvement in the revision of the Tizard report, with its analysis of a nuclear exchange between the UK and the USSR.
History And The Origins Of Life
Authors: Brown Andrew
Published: November 2023

Bernal’s friends were among the most important science writers of their time. Restricting the group to those who worked in England, and leaving aside C.P. Snow and J.G. Crowther who lived by their pens, they were remarkable for the range, quality and volume of their collective output. Haldane inherited H.G. Wells’ mantle as the best popular writer about science, but even he could not match the sales of Lancelot Hogben whose Mathematics for the Million: A Popular Self-Educator is estimated to have sold over half a million copies during its four editions. The doyen of the set was Joseph Needham, who abandoned his own career as an embryologist during the Second World War and devoted the remainder of his life to a landmark study of China, concentrating on the history of scientific development and the influence played by Chinese religion, politics and customs. Over a period of forty years, Needham published successive volumes of Science and Civilization in China, the early numbers of which were eagerly read, and often reviewed, by Sage. Needham came to believe that the predominance of Chinese science and technology for Wfteen hundred years and its subsequent eclipse by European science from the seventeenth century onwards could be understood only in terms of differences between the social and economic systems of China and the West – an historical approach stimulated by his conversations with Bernal in Cambridge before the war.
Peacebroking
Authors: Brown Andrew
Published: November 2023

Just as the dropping of the atomic bombs on Japan acted as the immediate stimulus for the disarmament movement after the war, the US thermonuclear weapon test at Bikini atoll on 1st March 1954 re-ignited global fear. The device, fuelled by lithium and an isotope of hydrogen, was at least one thousand times more powerful than the fission bomb dropped on Hiroshima. Its yield was also three times bigger than the Americans expected, because the scientists who developed it at Los Alamos had overlooked an important nuclear fusion reaction. The underwater explosion vaporized much of the atoll and caked the crew of the Japanese fishing boat, Lucky Dragon, with radioactive fallout though they were 80 miles away, outside the exclusion zone. The test had been preceded by the announcement of a new strategic policy of ‘massive retaliation’ by the US Secretary of State, John Foster Dulles, in January.
Order And Disorder
Authors: Brown Andrew
Published: November 2023

Both at home and abroad, Sage had close contacts with a wide range of scientists, reflecting the diversity of his own interests and the interdisciplinary nature of X-ray crystallography. He was an inspirational figure to colleagues everywhere – Linderstro’m Lang, who was the protein chemist in charge of the outstanding Carlsberg Laboratory in Copenhagen, told Perutz, ‘When Bernal comes to see me, I feel that my research is really worthwhile.’ Given how much time and effort Bernal spent as an unpaid consultant in science and technology to countries like China, India, and Russia in the 1950s, it would have been understandable if he had no enthusiasm left for the same role at home. He had, after all, written The Social Function of Science to stimulate others to think about the way science contributed to the British economy and way of life; he had done his best to revitalize research in England after the war, both at Birkbeck and by his frequent visits and talks at other universities. At the start of 1956, when he was still unable to persuade the university authorities that a separate department of crystallography needed to be established at Birkbeck, he decided it was time to review the whole issue of how scientific research was funded and organized in Britain. He sent out a memorandum to two hundred of the country’s leading scientists, politicians and university administrators. In his preamble, he made it clear that he was concentrating on the future of pure scientific research rather than on the subsequent economic and social application of scientific discoveries.
Problem Formulation
Authors: Tayler A B
Published: November 2023

Applied Mechanics is mathematics applied to those problem areas of science which arise from continuum considerations. Thus a macroscopic rather than an atomic or quantum view of the phenomena is adopted and attention directed to those areas in which observations or experiments are reproducible, and measured data are available in some form. The objective is to construct a mathematical simulation, or model, of a given scientific phenomenon, which agrees with existing measurements to within a specified accuracy and can be used with confidence to predict future observations and behaviour.
Asymptotic Methods For Non-Linear Problems
Authors: Tayler A B
Published: November 2023

In previous chapters nearly all the partial differential equations modelling the physical phenomena were linear, or they reduced to linear equations on applying a regular perturbation in some small parameter. For linear problems there is a considerable body of mathematical analysis available, so that in almost all cases it was possible to demonstrate clearly that the model was well posed.
A new look at the relationship between diversity and stability
Authors: Loreau M , Downing A , Emmerson M , Gonzalez A , Hughes J , lnchausti P , Joshi J , Norberg J , Sala O
Published: November 2023

The relationship between biodiversity and ecosystem functioning has emerged as one of the most exciting and controversial research areas in ecology over the last decade. Faced with the prospect of a massive, irreversible loss of biodiversity, ecologists have begun investigating the potential consequences of these dramatic changes in biodiversity for the functioning of natural and managed ecosystems. These investigations have been motivated by both the scientific challenge and the need to understand better the role biodiversity plays in providing sustainable ecological goods and services for human societies.
Introduction
Authors: Castel B , Towner I S
Published: November 2023

In 1956 Roger Blin-Stoyle wrote a very useful monograph [1] entitled Theories of Nuclear Moments. Since then the body of experimental data available on ground and excited states of nuclei has increased enormously. Not only are the spins, parities, and electromagnetic moments of ground states of most nuclei known, but today moments are routinely measured in short-lived isomers through advancements in such techniques as laser spectroscopy. Likewise, since 1956, there have been many theoretical advancements in the-understanding of the properties of nuclei. Yet the aim of this text remains the same as that of Blin-Stoyle’s: to discuss electromagnetic moments and their interpretation in terms of current nuclear theories.
Collective Models
Authors: Castel B , Towner I S
Published: November 2023

While the static moments of nuclei located close to the major shell closures are well described by the independent particle model (with core polarization and meson-exchange current corrections) nuclei further away from shell closures are characterized by non-spherical shapes and large quadrupole moments. To give a quantitative discussion of such nuclei will require a more phenomenological approach. It will be necessary to introduce some collective variables to describe cooperative modes of motion and a few intrinsic variables to describe the few extra-core nucleons not participating in the collective motion. Any coupling between the collective and intrinsic variables is taken as weak and studied through perturbation theory. Collective variables are only useful if the energy Hamiltonian can be separated into terms that depend on the collective variables and terms that do not. Then the eigenstates are of product form.