Atomfysik og molekylær fysik

Historisk spændingsroman om kapløbet om at skabe verdens første atombombe. LOS ALAMOS, JULI 1945. I et ørkenlandskab i New Mexico kæmper en række af verdens førende atomforskere med at konstruere det våben, som vil ændre verden for altid. Deriblandt Niels Bohr og en ung dansk ingeniør, David Adler. For David Adler bliver kapløbet om at udvikle atombomben et personligt drama om magt, hemmeligheder og kærlighed. Ligesom Niels Bohr må Adler træffe et valg i et moralsk dilemma med uoverskuelige konsekvenser. Steffen Jacobsen fik i 2013 sit store gennembrud med Trofæ, den første af en række spændingsromaner med makkerparret Michael Sander og Lene Jensen. "Er man til krimi, spænding og storstilede forbryderjagter, er man i godt selskab hos Steffen Jacobsen. Hans seje politifolk og detektiver sætter alle sejl til med risiko for liv og lemmer for at opklare de blodige, voldsomme og tilsyneladende usammenhængende hændelser, der udgør Jacobsens komplekse plot. Hans krimier er page-turners i bogstavelig forstand - og det kan være problematisk, for de er ikke korte!" - Fra portrættet på forfatterweb.dk

‘Hverdagsmad fra River Cottage’ er den ultimative grundkogebog for alle, der har en holdning til den mad, de spiser til daglig. Heri er samlet Hugh Fearnley-Whittingstalls bedste bud på økonomisk, sund og velsmagende hverdagsmad – og alle kan være med. Den frygtløse kok Hugh Fearnley-Whittingstall er kendt fra DR2’s programserie ‘River Cottage’, hvor han har lært danskerne om bedre madvaner, bæredygtighed og vigtigheden af gode råvarer. Ifølge Hugh er det nemlig sådan, at ændrer man menneskers holdning til mad, ændrer man deres holdning til livet! Og det er netop udgangspunktet for denne kogebog fra River Cottage, der med massevis af lækre opskrifter og tips til hverdagen giver et bud på en sundere hverdagskost for alle. Det er mad med holdning og velsmag.

En forårsaften i København 1925. En ung tysk videnskabsmand har en hel nat diskuteret atomfysik med sin mentor, professoren på Institut for Teoretisk Fysik. I Fælledparken ser den unge fysiker en mand, der bevæger sig ind og ud af gadelygternes lyskegler. En tilfældighed, der for altid vil ændre vores verdensbillede.Christian Haller – en af Schweiz’ mest velansete forfattere og selv naturvidenskabsmand – har skrevet en roman om sorg og ensomhed, om grænserne for vor viden og om de mest grundlæggende spørgsmål: Hvor pålidelig er vores opfattelse af verden? Hvor er genstandene, når vi ikke kan se dem? Hvordan tale om det usigelige?

Research has shown that students improve their problem-solving skills by working through puzzles, even from infancy. Children love working their way through a jigsaw, and as they watch the big picture emerging, they develop a sense of fulfilment and accomplishments. It is amazing how much students learn from wordsearches and puzzles.The goal is making Physics as a subject more accessible to more students. The path is through anagrams as brain teasers, wordsearches as builders of key vocabulary, crossword puzzles as concept keys, and the mind-maps to create the bigger picture, helping students appreciate why they are learning a topic.It promises to be an exciting journey. Why not start your students on the first step.Bon voyage!

This book provides an advanced introduction to extended theories of quantum field theory and algebraic topology, including Hamiltonian quantization associated with some geometrical constraints, symplectic embedding and Hamilton-Jacobi quantization and Becchi-Rouet-Stora-Tyutin (BRST) symmetry, as well as de Rham cohomology. This extended new edition offers a multifaced insight into phenomenology of particles such as baryons and photons, in terms of extended objects. In particular, in the second edition, the baryons are described in hypersphere soliton model, and the photon properties are additionally included in stringy photon model and in Dirac type relativistic quantum mechanics for a photon.It offers a critical overview of the research in this area and unifies the existing literatures, employing a consistent notation. Although the results presented apply in principle to all alternative quantization schemes, special emphasis is placed on the BRST quantization and its de Rham cohomology group which contribute to a deep understanding of constrained physical theories. The book describes how solitons and other models subject to constraints include rigorous treatments of the geometrical constraints which affect the predictions themselves. The book is intended for use by any graduate-level student with quantum field and relativity theories, and it also serves as a useful reference for those working in the field. An extensive bibliography guides the reader toward the source literature on particular topics.

This book proposes and develops the equilibrium compound nucleus post-fission theory, a powerful tool for studying the fission process and making numerical calculations of post-fission nuclear data. It begins with a detailed historical background on fission theory and covers fundamental concepts, such as the Bohr-Wheeler formula and time dependent nuclear density functional theory.The authors explain the kinematics of heavy-ion collisions and develop a heavy-ion spherical optical model. They also present the theoretical methods for calculating the yield, kinetic energy distribution, and angular distribution of fission fragments in the initial state of fission. In addition, readers are provided with the method for calculating the prompt neutron and prompt gamma-ray data as well as the proportion of the isomeric state nucleus and independent yield from the initial yield of the fission fragments. Using the nuclear decay data of the fission products, a method for calculating thecumulative yield and decay heat of the fission fragments is also given. A fission delayed neutron simplification model is proposed and the theoretical method for calculating the total contribution of three fission channels to post-fission nuclear data is provided.This book concludes with a step-by-step guide on numerical calculations for post-fission nuclear data and a Fortran program for optimizing the best theoretical model parameters. It is ideal for both junior and senior researchers in nuclear physics, as well as graduate students who are interested learning about the subject. Given the current interest in post-fission and the tremendous experimental and theoretical efforts in studying it, this book serves as a timely and comprehensive resource for the nuclear physics community.

This thesis describes how the rich internal degrees of freedom of molecules can be exploited to construct the first ¿clock¿ based on ultracold molecules, rather than atoms. By holding the molecules in an optical lattice trap, the vibrational clock is engineered to have a high oscillation quality factor, facilitating the full characterization of frequency shifts affecting the clock at the hertz level. The prototypical vibrational molecular clock is shown to have a systematic fractional uncertainty at the 14th decimal place, matching the performance of the earliest optical atomic lattice clocks. As part of this effort, deeply bound strontium dimers are coherently created, and ultracold collisions of these Van der Waals molecules are studied for the first time, revealing inelastic losses at the universal rate. The thesis reports one of the most accurate measurements of a molecule¿s vibrational transition frequency to date. The molecular clock lays the groundwork for explorations into terahertz metrology, quantum chemistry, and fundamental interactions at atomic length scales.

Classical mechanics is the basis for any university-level study of technical-scientific disciplines. But most existing manuals use a technological and engineering approach, with basic aspects sometimes insufficiently highlighted. This book introduces the concepts and applications of classical mechanics into Newtonian formalism. Newtonian dynamics is useful for solving applied physics and engineering problems, but also a fascinating theory anchored in questions posed since the times of the Greek philosophers, regarding space, the flow of time, measurable physical quantities, the physical principles with the mathematical structure needed to describe the Universe, etc. The author aims to encourage students to think about these fundamental aspects and how they will be addressed in modern physics, including the successes and limitations of Newton's mechanics. The book is designed to mirror the progress of the students using it, with earlier chapters assuming nomore than basic high school instruction and later ones geared toward subsequent enhanced understanding. The book is designed for students of undergraduate programs in physics, mathematics, chemistry, and engineering who will deal with modern physics, as they will benefit from an approach in which the aspects of classical mechanics are introduced in a propaedeutic approach towards relativistic physics and quantum mechanics.

This book highlights quantum optics technologies that can revolutionize the way we encode, store, transmit, and handle information. These technologies can help us overcome bottlenecks in classical physics-based information technology in information transmission capacity, computing speed, and information security. The book provides readers with new perspectives on potential applications of the quantum theory. Besides, the book summaries the research advances in quantum optics and atom optics, including manipulation and construction of the quantum states of photons and even atoms, molecules, and matter at the quantum level, and new phenomena and technologies brought about by the interactions between photons and the quantum states of matter. The book provides extensive and thoroughly exhaustive coverage of quantum optics. It is suitable for researchers and graduate students of optical physics and quantum optics.

This thesis presents significant new observations of nuclear wobbling, and thus expands our understanding of nuclear triaxiality and its prevalence in the nuclear chart. Triaxial nuclear shapes are a very rare phenomena and their experimental identification often relies on two unique signatures - nuclear wobbling motion and chiral rotation. While nuclear chirality is a well-studied phenomenon, experimental observations of wobbling nuclei are rather limited. With the identification of 135Pr and 187Au as wobblers, this work establishes triaxiality to be a general phenomenon present in different regions of the nuclear chart, irrespective of any particular spin or deformation. A major focus of this work is the detailed investigation of the different kinds of wobbling modes. Depending on the geometry of the nuclear system, wobbling can be classified into two types - longitudinal and transverse. This work has, for the first time, reported evidence of the possible coexistence of both forms of wobbling in a single nucleus. Another important result reported in this work is the very first observation of co-existing chiral and wobbling modes in the 135Pr nucleus. This thesis details the experimental methods that led to this breakthrough, along with pertinent theoretical interpretations.

This thesis makes significant advances in the use of microspheres in optical traps as highly precise sensing platforms. While optically trapped microspheres have recently proven their dominance in aqueous and vacuum environments, achieving state-of-the-art measurements of miniscule forces and torques, their sensitivity to perturbations in air has remained relatively unexplored. This thesis shows that, by uniquely operating in air and measuring its thermally-fluctuating instantaneous velocity, an optically trapped microsphere is an ultra-sensitive probe of both mass and sound. The mass of the microsphere is determined with similar accuracy to competitive methods but in a fraction of the measurement time and all while maintaining thermal equilibrium, unlike alternative methods. As an acoustic transducer, the air-based microsphere is uniquely sensitive to the velocity of sound, as opposed to the pressure measured by a traditional microphone. By comparison to state-of-the-art commercially-available velocity and pressure sensors, including the world¿s smallest measurement microphone, the microsphere sensing modality is shown to be both accurate and to have superior sensitivity at high frequencies. Applications for such high-frequency acoustic sensing include dosage monitoring in proton therapy for cancer and event discrimination in bubble chamber searches for dark matter. In addition to reporting these scientific results, the thesis is pedagogically organized to present the relevant history, theory, and technology in a straightforward way.

"Thermogenic Molecules: Dietary Conversion of Adipose Tissue" by Anusha Jahagirdar is a comprehensive guide that delves into the molecular mechanisms underlying energy expenditure and obesity. The book covers topics related to the biology of adipose tissue, including brown adipose tissue (BAT) and white adipose tissue (WAT), and their respective roles in regulating energy expenditure and metabolism. The book provides a thorough understanding of the molecular and cellular mechanisms of thermogenesis and how it contributes to energy expenditure. It discusses the role of mitochondria and uncoupling protein 1 (UCP1) in thermogenesis, as well as the activation of thermogenesis by sympathetic nervous system and catecholamines. The book also explores the regulation of nutrient sensing pathways, such as AMPK, mTOR, and PPARs, and their impact on thermogenesis and adipose tissue function. Furthermore, the book delves into the impact of various dietary components on thermogenesis, including carbohydrates, proteins, and fats, and the role of ketosis in regulating energy expenditure. It also discusses the impact of exercise, cold exposure, and diet-induced thermogenesis on adipose tissue function and energy expenditure. The book also covers the link between obesity and various diseases, such as diabetes, cardiovascular diseases, non-alcoholic fatty liver disease, and cancer, and how pharmacological interventions and natural compounds can modulate adipose tissue function and metabolism to prevent and treat these conditions. Overall, "Thermogenic Molecules: Dietary Conversion of Adipose Tissue" is a valuable resource for researchers, students, and professionals in the field of metabolism, nutrition, and obesity, providing a comprehensive overview of the molecular mechanisms regulating energy expenditure and their role in preventing and treating obesity-related diseases.

This book addresses the pursuit and further investigation of experimental results by analyzing classic examples from physics. The authors concentrate on the investigation of experimental results by examining case studies from the history of 20th and 21st century physics. Discussions on the discovery of parity nonconservation, the rise and fall of the Fifth Force, the search for neutrinoless double decay, supersymmetry and the expansion of the Standard Model, and measurements of the anomalous magnetic moment of the muons are provided. Experimental results may achieve acceptance to the point that even well known principles, such as conservation of energy and quantization, lose their status as accepted. Such principles and their options are treated on an equal footing as being pursuit worthy even though there is no plausible explanation as to why and how they might have failed.

This book provides a comprehensive overview of positron profilometry, specifically focusing on the analysis of defect depth distribution in materials. Positron profilometry plays a crucial role in understanding and characterizing defects in a wide range of materials, including metals, semiconductors, polymers, and ceramics. By analyzing the depth distribution of defects, researchers can gain insights into various material properties, such as crystal structure, defect density, and diffusion behavior. The author's extensive research spanning a period of two decades has primarily centered on subsurface zones. These regions, located beneath the surface and subjected to various surface processes, play a crucial role in generating defect distributions. Three experimental techniques and their data analysis are described in detail: a variable-energy positron beam (VEP) called sometimes a slow positron beam, a technique called implantation profile depth scanning (DSIP), and a sequential etching(SET) technique. The usability of these techniques is illustrated by many examples of measurements by the author and others.

This book provides a comprehensive, systematic description of modern timekeeping and its specializations. Introductory chapters discuss the concept of time and its definition, then briefly look at pre-Atomic Era timekeeping to set the stage for the introduction of the atomic clock. Subsequent chapters focus on concepts such as frequency stability and measurement uncertainty, as well as computer network time-synchronization protocols including Network Time Protocol (NTP) and Precise Time Protocol (PTP). The book then delves into the nuts and bolts of the Global Navigation Satellite Systems (GNSS), Two-Way Satellite Time and Frequency Transfer, and Optical Time and Frequency Transfer. Timescale theory is then described as a way to combine clock data, and the algorithms and procedures used to generate Coordinated Universal Time (UTC) are given. Finally, there is a look at modern applications of timekeeping and time transfer.Featuring a glossary of all key terms, this book is highly recommended for trained or incoming physicists, engineers, or mathematicians working, for example, in manufacturing or timing laboratories. Additionally, it is suitable for use in introductory university courses dealing with the subject of timekeeping.

This book provides a comprehensive introduction to all aspects of low-energy ion-solid interaction from basic principles to advanced applications in materials science. It features a balanced and insightful approach to the fundamentals of the low-energy ion-solid surface interaction, focusing on relevant topics such as interaction potentials, kinetics of binary collisions, ion range, radiation damages, and sputtering. Additionally, the book incorporates key updates reflecting the latest relevant results of modern research on topics such as topography evolution and thin-film deposition under ion bombardment, ion beam figuring and smoothing, generation of nanostructures, and ion beam-controlled glancing angle deposition. Filling a gap of almost 20 years of relevant research activity, this book offers a wealth of information and up-to-date results for graduate students, academic researchers, and industrial scientists working in these areas.

This book describes the forcefields/interatomic potentials that are used in the atomistic-scale and molecular dynamics simulations. It covers mechanisms, salient features, formulations, important aspects and case studies of various forcefields utilized for characterizing various materials (such as nuclear materials and nanomaterials) and applications. This book gives many help to students and researchers who are studying the forcefield potentials and introduces various applications of atomistic-scale simulations to professors who are researching molecular dynamics.

Sensors and Instrumentation, Aircraft/Aerospace and Energy Harvesting, Volume 7:  Proceedings of the 40th IMAC, A Conference and Exposition on Structural Dynamics, 2020, the seventh volume of nine from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Shock & Vibration, Aircraft/Aerospace, Energy Harvesting & Dynamic Environments Testing including papers on:Alternative Sensing & AcquisitionActive ControlsInstrumentationAircraft/Aerospace & Aerospace Testing Techniques Energy Harvesting

This book adopts a novel, physics-first approach to quantum measurement, using physical experiments as the basis to describe the underlying mathematical formalism. The text is an excellent introduction for students wanting to learn more about measurement theory, and the wide selection of exercises make this book ideal for courses.

The story that bonds Ernest Rutherford and Marcus Oliphant is as extraordinary as it is unlikely. They were kindred souls, schooled and steeped in the furthest frontiers of Britain's empire, whose restless intellect and tireless conviction fused in the crucible of discovery at Cambridge University's celebrated Cavendish Laboratory, at a time when nature's deepest secrets were being revealed. Their brilliance illuminated the sub-atomic recesses of the natural world and, as a direct result, set loose the power of nuclear fusion. It was a heartfelt, enduring partnership, born at the University of Adelaide's modest physics department and flourishing further in the confines of the Cavendish before ultimately driving the famed Manhattan Project, which produced the world's first nuclear weapons, unleashed to such devastating effect on Hiroshima and Nagasaki. Rutherford and Oliphant were men with a shared devotion to pure science, who, through circumstance and necessity, found themselves betrayed as instruments of the war they detested but were duty-bound to prosecute. Consequently, their influence was pivotal in the last great global conflict the world witnessed and in engendering the thermonuclear threat that has held the planet hostage ever since. Yet their pioneering work lives on too in a vast array of innovations seeded by nuclear physics, from radiocarbon dating and TV screens to life-saving diagnostic-imaging devices.