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Extended-Lorentz Quantum-Cosmology Symmetry Group

Unitarily representable by transformations of Milne quantum-universe (MQU) Hilbert-space vectors is a 9-parameter 'extended-Lorentz' Lie group whose algebra comprises 9 conserved MQU-constituent ('quc') attributes: electric charge, energy, spirality, 3-vector momentum and 3-vector angular momentum. Commutation with the full symmetry algebra by the 3-element Lorentz-extending sub-algebra identifies any quc by its (permanent) trio of charge, spirality and energy integers. Milne's redshift-specifying 'universe age' is invariant under the MQU symmetry group. Also invariant is the (elsewhere specified) universe hamiltonian--a self-adjoint age-dependent Hilbert-space operator (not a symmetry-algebra member) that generates universe evolution with increasing age through a 'Schrodinger' (first-order) differential equation.

physics.gen-ph↗

New subluminal and superluminal spacetime measures

In present work the author presents a new set of spacetime measures for both, subluminal and superluminal motion regimes, which do not diverge for the speed of light in the former case and each regime has its own light-like cone which warrants causality to each regime. For events located in the vicinity of the light cone and inside it, there exists the possibility to transit across the speed of light value in a discrete way, in terms of the very small constant which we introduce here to prevent the divergence of our spacetime measures at the speed of light.

physics.gen-ph↗

Gauge CPT as a Possible Alternative to the Dark Matter Hypothesis

A new force is proposed in order to explain galactic rotation curves. CPT is chosen as the underlying symmetry of the new force because it is a universal spacetime symmetry. Local CPT transformations are presented for the Dirac field (matter) and the vierbein describing curved spacetime. A nonvanishing variation of the Dirac action in curved spacetime is thus derived. Because the metric spin connection of general relativity cannot accommodate the variation induced by the local CPT symmetry, a new gauge field is introduced. The transformation of the new field is derived which implies the new field is massless. Experimental speculations based on the zero mass of the new gauge field are presented. It is shown that one type of Yang-Mills Lagrangian density is not invariant under local CPT transformations.

physics.gen-ph↗

The precise determination of mass through the oscillations of a very high-Q superconductor oscillating system

The present paper is based upon the fact that if an object is part of a highly stable oscillating system, it is possible to obtain an extremely precise measure for its mass in terms of the energy trapped in this resonance. The subject is timely since there is great interest in Metrology on the establishment of a new electronic standard for the kilogram. Our contribution to such effort includes both the proposal of an alternative definition for mass in terms of energy, as well as the description of a realistic experimental system in which this definition might actually be applied. The setup consists of an oscillating type-II superconducting loop (the SEO system) subjected to the gravity and magnetic fields. The system is shown to be able to reach a dynamic equilibrium by trapping energy up to the point it levitates against the surrounding magnetic and gravitational fields, behaving as an extremely high-Q spring-load system. The proposed energy-mass equation applied to the electromechanical oscillating system eventually produces a new experimental relation between mass and standardized constants.

physics.gen-ph↗

Coordinate Geometric Approach to Spherometer

The spherometer used for measuring radius of curvature of spherical surfaces is explicitly based on a geometric relation unique to circles and spheres. We present an alternate approach using coordinate geometry, which reproduces the well-known result for the spherometer and also leads to a scheme to study aspherical surfaces. We shall also briefly describe some of the modified spherometers.

physics.gen-ph↗

Physico-mathematical foundations of relativistic cosmology

I briefly present the foundations of relativistic cosmology, which are, General Relativity Theory and the Cosmological Principle. I discuss some relativistic models, namely, "Einstein static universe" and "Friedmann universes". The classical bibliographic references for the relevant tensorial demonstrations are indicated whenever necessary, although the calculations themselves are not shown.

physics.gen-ph↗

New conceptions on the light wave theory in a moving frame of reference

A reanalisis of the effect of a moving frame of reference is done, showing that the null result of the Michelson-Morley's experimente of 1887 on the possibility of detecting the variation of the velocity of light with respect to a moving observer, na observer at the Earth, was already implied in these equations; thereforewith no need of new ad hoc hypotheses to explain it in the classical framework. In fact, it will be shown that behind those equations is hidden the fascinating phenomenon of the absolute motion.

physics.gen-ph↗

Investigating of longitudinal development parameters through air shower simulation by different hadronic models

In this work the simulation of the Extensive Air Showers was performed by investigating the longitudinal development parameters (N and Xmax) by using a system for air shower simulation which is called AIRES version 2.6.0 at the energy range (10^14-10^19 eV) for different primary particles like (gamma, electron, positron, proton and iron nuclei) and different zenith angles. The comparison of simulated longitudinal profile was fulfilled for different hadronic models (SIBYLL, QGSJET99 and SIBYLL S16).

physics.gen-ph↗

On the Covariant Quantization of QED

The commutation relations for bosons are field independent, and can be reliably inferred from the definition of creation and annihilation operators. Here, the commutation relations are assumed known, and the quantum electrodynamics equations without sources are quantized with the unmodified Lagrangian. Non diagonal products of creation and annihilation operators of the form, cr(0)an(3)+ cr(3)an(0), where 0,3 denote respectively the time-like and longitudinal-polarizations, are present in both terms that contribute to the Hamiltonian. However, the contributions differ in sign, and therefore cancel. In units of the photon's energy the coefficients of the Hamiltonian's four polarization states are -1/2, 1, 1, 1/2, clearly revealing the unphysical character of the time like and longitudinal polarization states. If the physical states are restricted to those that do not contain unphysical polarization states, and if the Lorentz condition is satisfied, then the non diagonal terms of the field's momentum vanish, and both the Hamiltonian and Momentum are well behaved. A transformation of the basic vectors engenders in turn a transformation of the creation operators. The expression for the transformation that leaves invariant the commutation relations is derived.

physics.gen-ph↗

Quantum flights

The principles of quantum motors based on Casimir platforms (thin-film nanostructures are at issue) are discussed in plain language. The generation of quantum propulsion is caused by the noncompensated integral action of virtual photon momenta upon a configuration unit cell in the platform. The cells in a Casimir platform should be situated in a certain order with optimal geometric parameters. The evaluation of the quantum propulsion shows that, for example, ten square meters of ideal Casimir platforms (it is a complex single-layer structure) could make Cheops pyramid move!

physics.gen-ph↗

Klein-Gordon Transformation sans Extraneous Insertions: the Isomorphic Classical Complement to a Quantum System

The historical Klein-Gordon transformation of complex-valued first-order in time Schroedinger equations iterates these in a naively straightforward way which changes them into complex-valued second-order in time equations that have a plethora of extraneous solutions -- the transformation is an operator-calculus analogue of the squaring of both sides of an algebraic equation. The real and imaginary parts of a Schroedinger equation, however, are well known to be precisely the dynamical equation pair of the real-valued classical Hamiltonian functional which is numerically equal to the expectation value of that Schroedinger equation's Hermitian Hamiltonian operator. The purely real-valued second-order in time Euler-Lagrange equation of the corresponding classical Lagrangian functional is also isomorphic to that Schroedinger equation, and for symmetric Hamiltonians has exactly the same formal appearance as the corresponding naive complex-valued Klein-Gordon equation, but none of the latter's extraneous solutions. These quantum Schroedinger-equation isomorphisms to classical Euler-Lagrange equations are the technical manifestation of a key theoretical aspect of the principle of complementarity, one which is elegantly illustrated by the isomorphic free-photon wave-function complement to the vector potential of source-free classical electrodynamics.

physics.gen-ph↗

Harmonic oscillator: an analysis via Fourier series

The Fourier series method is used to solve the homogeneous equation governing the motion of the harmonic oscillator. It is shown that the general solution to the problem can be found in a surprisingly simple way for the case of the simple harmonic oscillator. It is also shown that the damped harmonic oscillator is susceptible to the analysis.

physics.gen-ph↗

Exact solution of rectangular Ising lattice in a uniform external field

A method is proposed for exactly calculating the partition function of a rectangular Ising lattice with the presence of a uniform external field. This approach is based on the method of the transfer matrix developed about seventy years ago for the rectangular Ising model in the absence of external field. The basis for the vector space is chosen as the eigenvectors of the diagonal part of the transfer matrix. The matrix elements for the non-diagonal part can be calculated very easily. Then the partition function and thermodynamical quantities can be evaluated. The limit of infinite lattice is discussed.

physics.gen-ph↗

Variable Tension, Large Deflection Ideal String Model For Transverse Motions

In this study a new approach to the problem of transverse vibrations of an ideal string is presented. Unlike previous studies, assumptions such as constant tension, inextensibility, constant crosssectional area, small deformations and slopes are all removed. The main result is that, despite such relaxations in the model, not only does the final equation remain linear, but, it is exactly the same equation obtained in classical treatments. First, an "infinitesimals" based analysis, similar to historical methods, is given. However, an alternative and much stronger approach, solely based on finite quantities, is also presented. Furthermore, it is shown that the same result can also be obtained by Lagrangian mechanics, which indicates the compatibility of the original method with those based on energy and variational principles. Another interesting result is the relation between the force distribution and string displacement in static cases, which states that the force distribution per length is proportional to the second spatial derivative of the displacement. Finally, an equation of motion pertaining to variable initial density and area is presented.

physics.gen-ph↗

A Simple Method for Generating Electromagnetic Oscillations

We propose a novel approach to the generation of electromagnetic oscillations by means of a low-frequency pumping of two coupled linear oscillators. A theory of such generation mechanism is proposed, and its feasibility is demonstrated by using coupled RLC oscillators. A comparison of the theoretical results and the experimental data is presented.

physics.gen-ph↗

Quantum electrodynamic theory of the cardiac excitation propagation I: construction of quantum electrodynamics in the bidomain

To provide a unified theoretical framework ranging from a cellular-level excitation mechanism to organic-level geometric propagation, a new theory inspired by quantum electrodynamic theory for light propagation is proposed by describing the cardiac excitation propagation as the continuation of absorption and emission of charged ions by myocardial cells. By the choice of gauge and the membrane current density, a set of Maxwell's equations with a charge density and a current density is constructed in macroscopic bidomain and is shown to be equivalent to the diffusion-reaction system with the B. van der Pol oscillator. The derived Maxwell's equations for the excitation propagation obeys the conservational laws of the number of the cations, energy and momentum, but the total charge is not conserved. The Lagrangian is derived to reveal that the trajectory and wavefront of the excitation propagation are the same as the electrodynamic wave if ion channels work uniformly. From the second quantization, the Hamiltonian is also derived to explain the excitation mechanism of the myocardial cell by Feynman's diagram and the mechanism of the refractory period in the perspective of positron. The effects of the external electromagnetic field are explained both from the action of the Lagrangian and the interaction by the Hamiltonian.

physics.gen-ph↗

A paradox about an atom and a photon

In this article we propose a new relativistic paradox concerning the absorption of a photon by a hydrogen atom. We show that the actual cause of the paradox is one of the hypotheses of Bohr model; therefore, in order to solve the paradox, we have to move away from Bohr model. Our analysis is carried out only in the special relativistic framework, so we are not interested in giving a full quantum mechanical treatment of the problem. We derive some expressions for emission and absorption of photons by atoms, which are in perfect agreement with special relativity, although comparable to the classical Bohr formula with an excellent degree of approximation. Quite interestingly, these expressions are no more invariant under a global shift of energy levels, showing a breaking of classical "gauge invariance" of energy. We stress that, to the best of our knowledge, the present approach has never been considered in literature. At the end we will be able to solve the proposed paradox.

physics.gen-ph↗

Compressed Baryonic Matter: from Nuclei to Pulsars

Our world is wonderful because of the negligible baryonic part although unknown dark matter and dark energy dominate the Universe. Those nuclei in the daily life are forbidden to fuse by compression due to the Coulomb repulse, nevertheless, it is usually unexpected in extraterrestrial extreme-environments: the gravity in a core of massive evolved star is so strong that all the other forces (including the Coulomb one) could be neglected. Compressed baryonic matter is then produced after supernova, manifesting itself as pulsar-like stars observed. The study of this compressed baryonic matter can not only be meaningful in fundamental physics (e.g., the elementary color interaction at low-energy scale, testing gravity theories, detecting nano-Hertz background gravitational waves), but has also profound implications in engineering applications (including time standard and navigation), and additionally, is focused by Chinese advanced telescopes, either terrestrial or in space. Historically, in 1930s, L. Landau speculated that dense matter at supra-nuclear density in stellar cores could be considered as gigantic nuclei (the prototype of standard model of neutron star), however, we address that the residual compact object of supernova could be of condensed matter of quark clusters. The idea that pulsars are quark-cluster stars was not ruled out during the last decade, and we are expecting to test further by future powerful facilities. (in Chinese)

physics.gen-ph↗