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First and Second Quantization

Henrik Bruus, Karsten Flensberg

Published Sep 2, 2004• 1 citation
Publisher

Abstract

Abstract Quantum theory is the most complete microscopic theory we have today describing the physics of energy and matter. It has successfully been applied to explain phenomena ranging over many orders of magnitude, from the study of elementary particles on the sub-nucleonic scale to the study of neutron stars and other astrophysical objects on the cosmological scale. Only the inclusion of gravitation stands out as an unsolved problem in fundamental quantum theory.

DOI
10.1093/oso/9780198566335.003.0001

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Abstract Quantum theory is the most complete microscopic theory we have today describing the physics of energy and matter. It has successfully been applied to explain phenomena ranging over many orders of magnitude, from the study of elementary particles on the sub-nucleonic scale to the study of neutron stars and other astrophysical objects on the cosmological scale. Only the inclusion of gravitation stands out as an unsolved problem in fundamental quantum theory.
Quantum theory is the most successful physical theory ever.About one third of the gross national product in the developed countries results from its applications.These applications range from nuclear power to most of the high-tech tools for computing, laser, solar cells and so on.No limit for its range of validity has been found up to now.Quantum theory has a clear mathematical structure, so a physics student can learn it in a short time.However, very often quantum theory is considered as being "crazy" or "not understandable".Such a stance appears reasonable as long as quantum theory is seen primarily as a theory of small particles and the forces between them.However, if quantum theory is understood more deeply, namely as a general theory of structures, not only the range is widely expanded, but it also becomes more comprehensible (T.Görnitz, 1999).Quantum structures can be material, like atoms, electrons and so on.They can also be energetic, like photons, and finally they can be mere structures, such as quantum bits.Keeping this in mind it becomes apprehensible that quantum theory has two not easily reconcilable aspects: on the one hand, it possesses a clear mathematical structure, on the other hand, it accounts for well-known experiences of everyday life: e.g. a whole is often more than the sum of its parts, and not only the facts but also the possibilities can be effective.If henadic and future structures (i.e.structures which are related to unity [Greek "hen"] and to future) become important in scientific analysis, then the viewable facts in real life differ from the calculated results of models of classical physics, which suppose elementary distinctions between matter and motion, material and force, localization and extension, fullness and emptiness and which describe any process as a succession of facts.From quantum theory one can learn two elementary insights:1.Not only facts but also possibilities can influence the way in which material objects behave.2. The elementary distinctions made in classical models are often useful, but not fundamental.Quantum theory shows that there are equivalences between the concepts of matter and motion, material and force, localization and extension, fullness and emptiness, and so on, www.intechopen.com How to referenceIn order to correctly reference this scholarly work, feel free to
This work presents a unified, realistic, and mechanically grounded interpretation of fundamental physics across all scales, from quarks and elementary particles to atoms, macroscopic bodies, planetary motion, and black holes. The proposed framework provides a single coherent physical description capable of reproducing and explaining, within a common dynamical structure, the full range of phenomena traditionally treated separately by general relativity, quantum mechanics, and quantum electrodynamics. Within this approach, long-standing conceptual problems such as wave–particle duality, quantum interference, entanglement, and wavefunction collapse are not postulated as fundamental features of nature, but emerge naturally as dynamical properties of a physically real medium. The apparent dual behavior of matter and radiation, as well as nonlocal quantum correlations, arise from coherent and topologically constrained excitations of this medium, without invoking probabilistic ontologies or nonphysical abstractions. The theory is based on a revised physical concept of space, treated as a real superfluid medium endowed with density, elasticity, viscosity, permittivity, permeability, and a very small but non-zero electrical conductivity. In this model, space is no longer a passive geometric background, but an active physical system capable of storing, transmitting, and dissipating energy.Mass is interpreted as an isotropic compression of the superfluid, electric charge as an oriented torsional configuration, and fields as elastic stress and vorticity distributions of the medium itself. Electromagnetic and gravitational waves are described as propagating perturbations of the superfluid, while particles correspond to stable solitonic configurations sustained by the medium dynamics.At the microscopic level, starting from classical fluid equations (continuity and Euler equations) and applying the Madelung transformation, the Schrödinger equation is shown to emerge as a compact complex representation of the underlying real fluid dynamics, rather than as a fundamental postulate. Quantum phenomena such as quantization, tunneling, spin, and exclusion principles follow from stability, coherence, and topological constraints of solitonic wave structures. On cosmological scales, the same framework provides a unified interpretation of redshift, large-scale expansion phenomena, and the cosmic microwave background as cumulative dynamical and dissipative effects of wave propagation within the superfluid medium, rather than as consequences of metric expansion alone. Effects commonly attributed to dark matter and dark energy are reinterpreted as emergent manifestations of spatial density gradients, elastic stresses, and dissipative properties of the superfluid, without introducing additional unknown components. A wide range of experimentally verified phenomena—including the photoelectric effect, Compton scattering, Zeeman–Stark effects, the Aharonov–Bohm effect, Casimir effect, Unruh radiation, and cosmological attenuation effects—are consistently described within this unified framework. The proposed model offers an alternative foundational paradigm for physics, in which space, matter, and interactions emerge from a single physically intelligible dynamical system, restoring a continuous and causal description of nature from microscopic to cosmological scales.
Quantum theory is perhaps the theory with the greatest predictive and explanatory success in all the history of physics. To name just a few of its countless achievements: it explains the stability of the stable atoms and nuclei and predicts the decay rates of the unstable ones; it accounts for the different manifestations of matter such as gaseous, liquid and solid, metallic and insulating, magnetic, superfluid and superconducting; it forms the basis of our chemical knowledge; and it provides the conceptual framework of all contemporary models for the fundamental constituents of matter. In addition, some of its predictions, for example that of the ‘electron spin g -factor’ in quantum electrodynamics, are perhaps the most accurate ones ever made in the history of science. Some of its predictions concern matter at extremely high energy and interactions between bits of matter at extremely short distances; others are about matter at extremely low energy and close to the zero of absolute temperature. As far as its technological applications are concerned, its insights are at the heart of the overwhelming technological progress in information technology in the past few decades, it explains why nuclear fission and fusion work as they do, and it forms the basis of the rapidly growing field of nanotechnology. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
The principle of least action, which has so successfully been applied to diverse fields of physics looks back at three centuries of philosophical and mathematical discussions and controversies. They could not explain why nature is applying the principle and why scalar energy quantities succeed in describing dynamic motion. When the least action integral is subdivided into infinitesimal small sections each one has to maintain the ability to minimize. This however has the mathematical consequence that the Lagrange function at a given point of the trajectory, the dynamic, available energy generating motion, must itself have a fundamental property to minimize. Since a scalar quantity, a pure number, cannot do that, energy must fundamentally be dynamic and time oriented for a consistent understanding. It must have vectorial properties in aiming at a decrease of free energy per state (which would also allow derivation of the second law of thermodynamics). Present physics is ignoring that and applying variation calculus as a formal mathematical tool to impose a minimization of scalar assumed energy quantities for obtaining dynamic motion. When, however, the dynamic property of energy is taken seriously it is fundamental and has also to be applied to quantum processes. A consequence is that particle and wave are not equivalent, but the wave (distributed energy) follows from the first (concentrated energy). Information, provided from the beginning, an information self-image of matter, is additionally needed to recreate the particle from the wave, shaping a “dynamic” particle-wave duality. It is shown that this new concept of a “dynamic” quantum state rationally explains quantization, the double slit experiment and quantum correlation, which has not been possible before. Some more general considerations on the link between quantum processes, gravitation and cosmological phenomena are also advanced.
This paper proposes a realist interpretive framework for quantum phenomena based on string theory—the Lamp Bead-Glow Model (LBM). The model uniformly describes quantum particles as composite systems of lamp beads (high-frequency localized vibrations of strings) and glow (extended physical fields excited by strings). It provides a self-consistent unified physical explanation for core quantum phenomena including wave-particle duality, double-slit interference, the Aharonov–Bohm effect, quantum tunneling, and quantum entanglement. On this basis, the concept of micro-gravitational domains is introduced: a single atom excites microscopic spacetime curvature units due to its rest mass, and the macroscopic gravitational field emerges as a gradient matter field through the linear superposition of a vast number of micro-gravitational domains. The curved spacetime geometry description of general relativity can be regarded as a low-energy effective approximation of this emergent field. The model naturally explains all classical gravitational phenomena explained by general relativity, such as the precession of Mercury’s perihelion, light bending near the Sun, and gravitational redshift. It also successfully explains the key observational fact that in the GW170817 binary neutron star merger, gravitational waves arrived about 1.7 seconds earlier than electromagnetic waves, attributing this time difference to the difference between the triggering of gravitational wave superposition thresholds and the moment of astrophysical collision, thereby overcoming inherent logical contradictions in mainstream explanations. At the same time, this paper presents a series of falsifiable experimental predictions, including the neutral atom Aharonov–Bohm effect, equal-kinetic-energy electron comparison experiments, and a mesh-grating baffle decisive experiment, the latter of which can be immediately conducted in ordinary laboratories with decisive discriminatory power. This paper systematically discusses the current theoretical limitations of the framework and future research directions, aiming to provide a testable realist conceptual foundation for the unification of quantum mechanics and gravity, rather than claiming to be a final theory