Kvantefysik (kvantemekanik og kvantefeltteori)

This book summarizes the state-of-the-art advances in the area of computational modelling of molecule-based magnets. Nowadays, various computational tools based on DFT, ab initio methods and other techniques are gaining attention in molecular nanomagnets and are successfully used to solve several outstanding problems in this area. This contributed volume discusses the theoretical foundation of the modelling of molecular magnets, starting from fitting the experimental magnetic data of very large molecules to the theory of pseudo-spin Hamiltonian approach and spin-phonon relaxations mechanisms, while it also presents examples of contemporary applications of both transition metal and lanthanide molecular magnets. In addition, the transport characteristics of molecules when placed at an interface and how these assemble on surfaces are also reviewed. This book is a great tool for researchers working in the fields of molecular magnetism and computational/theoretical chemistry and will also benefit graduate students specializing in physical-inorganic chemistry and molecular modelling.Chapter 6 is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

This book is on the nonlinear random medium analysis that includes subtopics of terahertz imaging, inverse scattering, plasmonics, quantum optics/communication laser modes, and terahertz photonic antennas. Here in this book, a mathematical framework is developed to analyze the impact of dimensions and chemical potential on nano-antenna channels.

It is shown that electromagnetic forces like gravitation can be related to variations in the metric tensor provided, time like space is three dimensional. Time coordinates are given by imaginary numbers. The 4-axes in Minkowski space represents one direction in an orthogonal coordinate system (4, 5, 6). Electrons and positrons are assumed to be tiny black holes. At the surface of a black hole the unit length of the 4-axes equals zero, and time flow is assumed to take place as rotations in the 4, 5-plane generating charge. Based on this view of electric charge classical electrodynamics is evolved, and a model of the electron is constructed. From that model Plank’s constant is estimated as a function of the speed of light, the elementary charge and Coulomb’s constant. The model unavoidably leads to quantum mechanics. It is assumed that time can flow in the 5, 6-plane between two tiny black holes, one acting as source and one as sink. From hybrids between such elements and electrons/ positrons the basic two quarks, and hence protons and neutrons, can be built up. Pairs of such source/sink elements are identified as neutrinos.

This edited collection provides new perspectives on some metaphysical questions arising in quantum mechanics. These questions have been long-standing and are of continued interest to researchers and graduate students working in physics, philosophy of physics, and metaphysics. It features contributions from a diverse set of researchers, ranging from senior scholars to junior academics, working in varied fields, from physics to philosophy of physics and metaphysics. The contributors reflect on issues about fundamentality (is quantum theory fundamental? If so, what is its fundamental ontology?), ontological dependence (how do ordinary objects exist even if they are not fundamental?), realism (what kind of realism is compatible with quantum theory?), indeterminacy (can the world itself exhibit ontological indeterminacy?). The book contains contributions from both physicists (including Nobel Prize winner Gerard 't Hooft), science communicators and philosophers. 

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.

This book deals with theoretical mechanics. Newton published the "Philosophiæ Naturalis Principia Mathematica" in 1687. In it, he sets out the basic principles of physics that are required to understand the motion of the planets, their moons, and the comets in the solar system. It includes the gravitational (inverse square) law, the inertial principle, and the basic elements of mechanics. Since its publication, a large number of refinements and reformulations have been introduced, thereby adding enormous insight into the structure of mechanics, which is commonly known as ¿classical mechanics¿. All these have in common that by taking a suitable limit, Newton's original principles re-appear. Thus, physicists and mathematicians who work on the subject always have a notion that if their theories do not return to Newton's foundations, then there is something wrong. Newton himself acknowledged that 'if I have seen further (than others), it is by standing on the shoulders of giants'. One of these giants was undoubtedly Galileo who died in the year Newton was born. So, Newton himself adhered to the 'classical limit'.

This volume collects papers based on lectures given at the XXXIX Workshop on Geometric Methods in Physics, held in Biäystok, Poland in June 2022. These chapters provide readers an overview of cutting-edge research in geometry, analysis, and a wide variety of other areas. Specific topics include:Classical and quantum field theoriesInfinite-dimensional groupsIntegrable systemsLie groupoids and Lie algebroidsRepresentation theoryGeometric Methods in Physics XXXIX will be a valuable resource for mathematicians and physicists interested in recent developments at the intersection of these areas.

. The main aim of this book is to shine a spotlight on key experiments and their crucial importance for advancing our understanding of physics. Physics is an empirical science, and experiments have always been a driving force in the development of our understanding of nature. Facts matter. In that sense, the book attempts to be complementary to the many popularizations of theoretical physics, and to counterbalance the frequent emphasis there on more speculative ideas.Experimental physics is also an essential pillar in physics teaching, as well as helping broader audiences to better understand important concepts, particularly in challenging fields such as relativity or quantum physics, where our common sense intuition often fails.Readers are taken on an historical journey, starting with ¿Free Fall¿ and culminating in ¿Spooky Action at a Distance¿. En route they will encounter many important branches ofphysics, whose main ideas and theoretical description will be given a more empirical meaning. At the end, the reader is invited to reflect on what could be exciting and important directions for fundamental physics. All readers with an undergraduate degree in physical sciences or engineering will enjoy and learn much from this stimulating and original text.

"Provides a broad and accessible introduction to quantum field theory and the Standard Model of particle physics, adopting a distinctive pedagogical approach with clear intuitive explanations to complement the mathematical exposition. Includes topics of current research both within and beyond the Standard Model"--

This comprehensive second edition will allow readers to develop a working understanding of quantum computing as part of their general education or as a prelude to independent research on quantum computing.

Die beiden Bände von Quantenmechanik zu Fuß führen Schritt für Schritt in die Grundlagen der nichtrelativistischen Quantenmechanik ein.Dieser erste Band konzentriert sich hauptsächlich auf die wesentlichen Prinzipien, während Anwendungen und Erweiterungen des Formalismus in Band 2 zu finden sind.Um die Grundideen der Quantenmechanik und ihre mathematische Formulierung schnell und anschaulich darzustellen, wird in den ersten Kapiteln systematisch zwischen analytischer und algebraischer Darstellung gewechselt. Auf diese Weise können neben dem traditionellen Lehrstoff frühzeitig auch aktuelle Themen detailliert besprochen werden, wie z.B. Neutrino-Oszillationen und Quantenkryptographie. Ausgearbeitete Beispiele erleichtern den Zugang. Die erforderlichen mathematischen Werkzeuge werden dabei nach Bedarf eingeführt. Ein weiterer Schwerpunkt ist die Darstellung und Diskussion des Messproblems und anderer grundlegender konzeptueller Fragen. Ein Kapitel über die Postulate der Quantenmechanik schließt diesen ersten Band ab.Im Anhang findet sich eine kompakte Zusammenfassung der wichtigsten mathematischen Hilfsmittel, sodass auf ergänzende Literatur verzichten werden kann. Außerdem werden dort weiterführende Themen wie der Quanten-Zeno-Effekt und Time-delay-Experimente behandelt. Über 250 Übungsaufgaben mit ausführlichen Lösungen helfen dabei, das Verständnis für die behandelten Themen zu vertiefen.Die vorliegende überarbeitete und aktualisierte zweite Auflage ist um eine Einführung in einige Ideen und Probleme der relativistischen Quantenmechanik erweitert. In diesem ersten Band werden die Klein-Gordon- und die Dirac-Gleichung behandelt. Für die Relativistik benötigte Grundlagen anderer Gebiete werden in kompakter Form bereit gestellt (spezielle Relativitätstheorie, klassische Feldtheorie und Elektrodynamik).Quantenmechanik zu Fuß richtet sich an alle Studierenden der Physik und andere, die eine angemessen einfache, frische und moderne Einführung in die Quantenmechanik suchen. Das Buch eignet sich auch sehr gut zum Selbststudium.

Die beiden Bände von Quantenmechanik zu Fuß führen Schritt für Schritt in die Grundlagen der nichtrelativistischen Quantenmechanik ein.Während sich der erste Band mit den wesentlichen Prinzipien befasst, werden in diesem zweiten Band Anwendungen und Erweiterungen auf komplexere Probleme erörtert.Neben Gebieten, die zum traditionellen Stoff der Quantenmechanik gehören wie z.B. Symmetrien, Streutheorie oder Vielteilchenprobleme, werden auch aktuelle Themen ausführlich behandelt, etwa Verschränkung, Bellsche Ungleichung, Dekohärenz, Quantencomputer und andere Aspekte der Quanteninformation. Ausgearbeitete Beispiele erleichtern den Zugang. Die Realismusdebatte und andere konzeptuelle Fragen der Quantenmechanik werden ausführlich besprochen. Ein Kapitel über die Interpretationen der Quantenmechanik schließt diesen zweiten Band ab.Im Anhang wird das erforderliche mathematische Handwerkszeug kompakt zusammengestellt. Außerdem werden dort weiterführendeThemen wie der Lenz-Vektor, das Hardy-Experiment und der Shor-Algorithmus detailliert dargestellt. Über 150 Übungsaufgaben mit ausführlichen Lösungen helfen dabei, das Verständnis für die behandelten Themen zu vertiefen. Die vorliegende überarbeitete und aktualisierte zweite Auflage ist um eine Einführung in einige Ideen und Probleme der relativistischen Quantenmechanik erweitert. In diesem zweiten Band wird ein Überblick über die Quantenfeldtheorie gegeben und grundlegende Konzepte der Quantenelektrodynamik eingehend behandelt.Quantenmechanik zu Fuß richtet sich an alle Studierenden der Physik und andere, die eine angemessen einfache, frische und moderne Einführung in die Quantenmechanik suchen. Das Buch eignet sich auch sehr gut zum Selbststudium.

This book presents a complementary perspective to Schrodinger theory of electrons in an electromagnetic field, one that does not appear in any text on quantum mechanics. The perspective, derived from Schrodinger theory, is that of the individual electron in the sea of electrons via its temporal and stationary-state equations of motion - the 'Quantal Newtonian' Second and First Laws. The Laws are in terms of 'classical' fields experienced by each electron, the sources of the fields being quantum-mechanical expectation values of Hermitian operators taken with respect to the wave function. Each electron experiences the external field, and internal fields representative of properties of the system, and a field descriptive of its response. The energies are obtained in terms of the fields. The 'Quantal Newtonian' Laws lead to physical insights, and new properties of the electronic system are revealed. New mathematical understandings of Schrodinger theory emerge which show the equation to be intrinsically self-consistent.  Another complimentary perspective to Schrdinger theory is its manifestation as a local effective potential theory described via Quantal Density Functional theory. This description too is in terms of 'classical' fields and quantal sources. The theory provides a rigorous physical explanation of the mapping from the interacting system to the local potential theory equivalent.The complementary perspective to stationary ground state Schrdinger theory founded in the theorems of Hohenberg and Kohn, their extension to the presence of a magnetic field and to the temporal domain - Modern Density Functional Theory -- is also described. The new perspectives are elucidated by application to analytically solvable interacting systems. These solutions and other relevant wave function properties are derived.

Chemische Bindung und Spektroskopie sind sehr wichtige Themen der Chemie. Ein Verständnis von diesen ist nicht ohne ein Verständnis der Quantentheorie möglich, und deswegen ist eine Einführung in Quantentheorie und deren Anwendungen für Chemiestudierende essentiell. Das vorliegende Lehrbuch bietet eine solche Einführung an, die sich für ein Bachelorkurs in einem Semester im 2ten Studienjahr geeignet ist, und die wenige Vorkenntnisse verlangt. Das Buch bringt zuerst eine Einführung in Grundlagen der Quantentheorie, und anschließend wird sie für verschiedene, chemisch relevante Systeme verwendet. Vor allem werden die elektronischen Eigenschaften von Atomen und Molekülen sowie die Grundlagen der chemischen Bindungen behandelt. Letztendlich werden auch die Grundlagen der verschiedenen, sehr häufig eingesetzten Methoden der Computerrechnungen behandelt, womit Eigenschaften von Atomen, Molekülen und Kristallen berechnet werden können. Solche Rechnungen sind heutzutage Standard der chemischen Forschung.

As we enter the quantum era, new research on applying the rules of quantum physics to biology, which was previously considered impossible, has revolutionized our understanding and our concept of molecular and atomic particles behavior and their interactions. This book is the first comprehensive review of the quantum biology of the visual system. Chapters discuss the relevance of quantum physics to the biological systems, especially in the visual system. The main purpose of this book is to simplify quantum biology concepts relevant to physiology of human eye and to help the reader understand the essentials of this new emerging, complex and anti-intuitive field of science. It offers a contemporary view of the emerging interplay between the biochemistry, physiology, molecular biology, and molecular and atomic particle quantum characteristics such as vibration, spin etc.Quantum Biology of the Eye is an essential resource for Ophthalmologists, physicians, residents, fellows, all fields of visual science and medical students in ophthalmology, and other converging fields of science such as visual optics biochemists, psychology etc.

Over the last ten years, elements of the formalism of quantum mechanics have been successfully applied beyond physics in areas such as psychology (especially cognition), economics and finance (especially in the formalization of so-called ¿decision making¿), political science, and molecular biology. An important stream of work along these lines, commonly under the heading of quantum-like modeling, has been published in well regarded scientific journals, and major publishers have devoted entire books to the topic. This Festschrift honors a key figure in this field of research: Andrei Khrennikov, who made momentous contributions to it and to quantum foundations themselves. While honoring these contributions, and in order to do so, this Festschrift orients its reader toward the future rather than focusing on the past: it addresses future challenges and establishes the way forward in both domains, quantum-like modeling and quantum foundations. A while ago, in response to the developments of using the quantum formalism outside of quantum mechanics, the eminent quantum physicist Anton Zeilinger said, ¿Why should it be precisely the quantum mechanics formalism? Maybe its generalization would be more adequate¿¿ This volume responds to this statement by both showing the reasons for the continuing importance of quantum formalism and yet also considering pathways to such generalizations. Khrennikov¿s work has been indispensable in establishing the great promise of quantum and quantum-like thinking in shaping the future of scientific research across the disciplines.

The Quantumania World Is Real is a mind-expanding journey into the fascinating realm of quantum physics and its profound impact on our understanding of reality. Delve into the mysterious and awe-inspiring world where particles can exist in multiple states simultaneously, where time and space become fluid, and where the very fabric of the universe is woven with uncertainty.In this thought-provoking book, you'll embark on an exploration of the quantum frontier, guided by renowned scientists and experts who unravel the complexities of quantum mechanics. From the famous double-slit experiment to the mind-bending concepts of entanglement and superposition, you'll witness the astonishing phenomena that challenge our traditional notions of how the world works.As you delve deeper into the Quantumania World, you'll encounter mind-boggling concepts that defy intuition and stretch the boundaries of human comprehension. Discover the potential applications of quantum computing, quantum cryptography, and quantum teleportation, and grasp the transformative implications they hold for our technological advancements.But The Quantumania World is not just about scientific theories and abstract concepts. It explores the profound philosophical, spiritual, and existential questions that arise when we confront the strange and wondrous world of quantum physics. How does our observation shape reality? What does it mean for our understanding of consciousness and free will? Prepare to have your worldview challenged and expanded.Whether you're a curious science enthusiast, a student of physics, or simply an open-minded seeker of knowledge, The Quantumania World invites you to embark on a journey that will transform your perception of reality. Prepare to be captivated by the beauty and mysteries of the quantumania realm as you explore the forefront of scientific exploration and uncover the wonders that lie beyond our everyday experience.

This textbook covers the physics of engineering materials and the latest technologies used in modern engineering projects. It has been designed for use as a reference book and course material for undergraduate engineering students. The book was born out of the need for a comprehensive, balanced, and up-to-date guide for teaching physics to beginning undergraduate engineering students and creating examination papers for technical boards and institutes. The text is divided into ten chapters, each with its specific objectives and features. The topics covered include the classification of engineering materials, atomic structure, electrical and magnetic behavior of solids, quantum mechanics, laser technology, nanomaterials, and sustainable development.Authored by a physicist with over 40 years of teaching experience, this richly-illustrated textbook features an abundance of self-assessment questions, solved examples, and a variety of chapter-end questions with detailed answers. The textbook starts from the very basics and is developed to the desired level, thus making it ideal as standalone course material.

By the star physicist and author of multiple #1 Sunday Times bestsellers, a major and definitive narrative work on black holes and how they can help us understand the universe. At the heart of our galaxy lies a monster so deadly it can bend space, throwing vast jets of radiation millions of light years out into the cosmos. Its kind were the very first inhabitants of the universe, the black holes.Today, across the universe, at the heart of every galaxy, and dotted throughout, mature black holes are creating chaos. And in a quiet part of the universe, the Swift satellite has picked up evidence of a gruesome death caused by one of these dark powers. High energy X-ray flares shooting out from deep within the Draco constellation are thought to be the dying cries of a white dwarf star being ripped apart by the intense tides of a supermassive black hole ? heating it to millions of degrees as it is shredded at the event horizon.They have the power to wipe out any of the universe's other inhabitants, but no one has ever seen a black hole itself die. But 1.8 billion light years away, the LIGO instruments have recently detected something that could be the closest a black hole gets to death. Gravitational waves given off as two enormous black holes merge together. And now scientists think that these gravitational waves could be evidence of two black holes connecting to form a wormhole ? a link through space and time. It seems outlandish, but today's physicists are daring to think the unthinkable ? that black holes could connect us to another universe.At their very heart, black holes are also where Einstein's Theory of General Relativity is stretched in almost unimaginable ways, revealing black holes as the key to our understanding of the fundamentals of our universe and perhaps all other universes.Join Professors Brian Cox and Jeff Forshaw in exploring our universe's most mysterious inhabitants, how they are formed, why they are essential components of every galaxy, including our own, and what secrets they still hold, waiting to be discovered.

Thermodynamicsisaspecialtheoryindeed.Aprincipletheory,aphenomenological onemoreover,thatoutgrewitsinitialpurposeofadvancingnineteenthcentury engineeringalmostassoonasitwasborn1.Ceasingtobeameretoolforthe optimisationofsteamenginesandthelike,thermodynamicsinsteadbecameatheory about,well,'almosteverything'.Butthisisnottosaythatthermodynamicscan provideuswiththeanswerstoallscientificquestions,quitethecontrary:traditionally, itfocussesonanarrowrangeofprocesses,singledoutbytheusageoftermssuchas heat,entropyandtemperature.Whatmakesthermodynamicssospecial,whatsets itapartfromotherphysicaltheories,isthecomprehensiveapplicationofitslawsto thoseothertheories.Quantuminformationtheory,quantumfieldtheory,general relativityandevenstringtheory,nottomentionchemistryandbiology-thelaws ofthermodynamicsareubiquitousamongourscientifictheories.

This book discusses the modern theory of Laplace eigenfunctions through the lens of a new tool called geodesic beams. The authors provide a brief introduction to the theory of Laplace eigenfunctions followed by an accessible treatment of geodesic beams and their applications to sup norm estimates, L^p estimates, averages, and Weyl laws. Geodesic beams have proven to be a valuable tool in the study of Laplace eigenfunctions, but their treatment is currently spread through a variety of rather technical papers. The authors present a treatment of these tools that is accessible to a wider audience of mathematicians. Readers will gain an introduction to geodesic beams and the modern theory of Laplace eigenfunctions, which will enable them to understand the cutting edge aspects of this theory.

This contributed volume overviews recently presented approaches for carrying out QSPR/QSAR analysis by using a simplifying molecular input-line entry system (SMILES) to represent the molecular structure. In contrast to traditional SMILES, quasi-SMILES is a sequence of special symbols-codes that reflect molecular features and codes of experimental conditions. SMILES and quasi-SMILES serve as a basis to develop QSPR/QSAR as well Nano-QSPR/QSAR via the Monte Carlo calculation that provides the so-called optimal descriptors for QSPR/QSAR models. The book presents a reliable technology for developing Nano-QSPR/QSAR while it also includes the description of the algorithms of the Monte Carlo optimization. It discusses the theory and practice of the technique of variational authodecoders (VAEs) based on SMILES and analyses in detail the index of ideality of correlation (IIC) and the correlation intensity index (CII) which are new criteria for the predictive potential of the model. The mathematical apparatus used is simple so that students of relevant specializations can easily follow. This volume is a valuable contribution to the field and will be of great interest to developers of models of physicochemical properties and biological activity, chemical technologists, and toxicologists involved in the area of drug design.

The nonlinear optical spectrum signal technology is a new type of optical characterization technology owing to its non-invasiveness and good biocompatibility. This book highlights a comprehensive introduction to the Stimulated Raman scattering (SRS), Anti-Stokes Raman Spectroscopy (CARS), Two-photon Excited Fluorescence (TPEF) and Second Harmonic Generation signals (SHG) technologies. The four types of nonlinear optical signals technologies, especially two-dimensional and three-dimensional imaging, have great application potential in physics, materials science, chemistry and biomedicine. The book covers principles, theoretical calculation methods, signal measurement methods and imaging specific methods. The theoretical part starts from the basics of nonlinear optics and the relationship with strong light, and gradually transitions to theoretical calculation methods for specific optical signals. it combines the classical theory and the quantum theory to help readers develop a thorough understanding of the technologies. The book is a good reference for graduate students majored in physics and chemistry and for researchers working on optics, photonics and materials science.

This book gives a comprehensive account of modern x-ray science, based on the use of synchrotron radiation and x-ray-free electron lasers (XFELs). It emphasizes the new capabilities of XFELs which extend the study of matter to the intrinsic timescales associated with the motion of atoms and chemical transformations and give birth to the new field of non-linear x-ray science. Starting with the historical understanding of the puzzling nature of light, it covers the modern description of the creation, properties, and detection of x-rays within quantum optics. It then presents the formulation of the interactions of x-rays with atomic matter, both, from semi-classical and first-principles quantum points of view. The fundamental x-ray processes and techniques, absorption, emission, Thomson, and resonant scattering (REXS and RIXS) are reviewed with emphasis on simple intuitive pictures that are illustrated by experimental results. Concepts of x-ray imaging and diffractive imaging of atomic and nano structures are discussed, and the quantum optics formulation of diffraction is presented that reveals the remarkable quantum substructure of light. The unique power of x-rays in providing atom and chemical-bond specific information and separating charge and spin phenomena through x-ray polarization (dichroism) effects are highlighted. The book concludes with the discussion of many-photon or non-linear x-ray phenomena encountered with XFELs, such as stimulated emission and x-ray transparency.