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Proofs of Vector Identities Using Tensors

The vector algebra and calculus are frequently used in many branches of Physics, for example, classical mechanics, electromagnetic theory, Astrophysics, Spectroscopy, etc. Important vector identities with the help of Levi-Civita symbols and Kronecker delta tensor are proved and presented in this paper. Some of the identities have been proved using Levi-Civita Symbols by other mathematicians and Physicists. The rests are presented for the first time. The derivations are of interest for both graduate and undergraduate students.

physics.gen-ph↗

Towards an axiomatic model of fundamental interactions at Planck scale

By exploring possible physical sense of notions, structures, and logic in a class of noncommutative geometries, we try to unify the four fundamental interactions within an axiomatic quantum picture. We identify the objects and algebraic operations which could properly encode the formation and structure of sub-atomic particles, antimatter, annihilation, CP-symmetry violation, mass endowment mechanism, three lepton-neutrino matchings, spin, helicity and chirality, electric charge and electromagnetism, as well as the weak and strong interaction between particles, admissible transition mechanisms (e.g., muon to muon neutrino, electron, and electron antineutrino), and decays (e.g., neutron to proton, electron, and electron antineutrino).

physics.gen-ph↗

Tensor of the energy - momentum and forbiddance of the classical Lump

We show that the static solutions of massive classical fields are forbidden in the Minkowski space time with dimensions higher than $2$. The purpose of this study is to generalize the forbiddance of the time independent localized classical fields in general space time. We generalize the Derrick theorem as unstable stationary localized solutions for the nonlinear wave equation or the nonlinear Klein - Gordon equation in Minkowski space time. Our approach employs the tensor of the energy - momentum based on Weber's method. We exploite the Bateman - Caldilora - Kanai model and the Deser method for the research of the Yang - Mills Lumps as massive solutions. We also use Riemann's coordinates for parametrization of tangent space as a local framework. The important point of this article is the homomorphism between the Minkowsian and pseudo Riemann's manifolds.

physics.gen-ph↗

Analysis of Free Will and Determinism in Physics

It is considered the study of determinism in the theories of physics. Based on fundamental postulates of physics, it is proved that the evolution of the universe is univocally determined, proving ultimately that free will does not exist. In addition, it is presented some contradictions and weaknesses of quantum mechanics, suggesting paradoxes in the theory. It is also analyzed some consequences of the postulates in justice and ethics.

physics.gen-ph↗

Consciousness and the Physical World

Edited proceedings of an interdisciplinary symposium on consciousness held at the University of Cambridge in January 1978. The purpose of the Cambridge conference was to encourage distinguished scientists to express their views on the relationship of conscious experience to the physical world.

physics.gen-ph↗

Simplicity in cosmology: add virialisation, remove $Λ$, keep classical GR

Present-day extragalactic observations are mostly rather well-modelled by a general-relativistic model, the $Λ$ CDM model. The model appears to surpass the limits of known physics by requiring that the Universe be dominated by "dark energy". However, the model sacrifices physical simplicity in favour of applied mathematical simplicity. A physically simpler, general-relativistic alternative to the $Λ$ CDM model is described here, along with preliminary observational checks. Thus, it will be argued that extragalactic observations such as the distance-modulus--redshift relation of type Ia supernovae are well-modelled within classical general relativity, without the addition of "new physics".

physics.gen-ph↗

Materials Bound by Non-Chemical Forces: External Fields and the Quantum Vacuum

We discuss materials which owe their stability to external fields. These include: 1) external electric or magnetic fields, and 2) quantum vacuum fluctuations in these fields induced by suitable boundary conditions (the Casimir effect). Instances of the first case include the floating water bridge and ferrofluids in magnetic fields. An example of the second case is taken from biology where the Casimir effect provides an explanation of the formation of stacked aggregations or "rouleaux" by negatively charged red blood cells. We show how the interplay between electrical and Casimir forces can be used to drive self-assembly of nano-structured materials, and could be generalized both as a probe of Casimir forces and as a means of manufacturing nanoscale structures. Interestingly, all the cases discussed involve the generation of the somewhat exotic negative pressures. We note that very little is known about the phase diagrams of most materials in the presence of external fields other than those represented by the macroscopic scalar quantities of pressure and temperature. Many new and unusual states of matter may yet be undiscovered.

physics.gen-ph↗

Biological Electric Fields and Rate Equations for Biophotons

Ultraweak bioluminescence - the emission of biophotons - remains an experimentally well-established, but theoretically poorly understood phenomenon. This paper presents several related investigations into the physical process of both spontaneous biophoton emission and delayed luminescence. Since light intensities depend upon the modulus squared of their corresponding electric fields we first make some general estimates about the inherent electric fields within various biological systems. Since photon emission from living matter following an initial excitation ("delayed luminescence") typically does not follow a simple exponential decay law after excitation we discuss such non-exponential decays from a general theoretical perspective and argue that they are often to be expected and why. We then discuss the dynamics behind some nonlinear rate equations, connecting them both to biological growth rates and biophoton emission rates, noting a possible connection with cancer. We then return to non-exponential decay laws seen for delayed luminescence in an experimental context and again note a possible connection with cancer.

physics.gen-ph↗

Seeable matter; unseeable antimatter

The universe we see gives every sign of being composed of matter. This is considered a major unsolved problem in theoretical physics. Using the mathematical modeling based on the algebra ${\bf{T}} := {\bf{C}}\otimes{\bf{H}}\otimes{\bf{O}}$, an interpretation is developed that suggests that this seeable universe is not the whole universe; there is an unseeable part of the universe composed of antimatter galaxies and stuff, and an extra 6 dimensions of space (also unseeable) linking the matter side to the antimatter - at the very least.

physics.gen-ph↗

The expectation value of the field operator

Much of the mathematical development of quantum field theory has been in support of determining the S-matrix in order to calculate scattering cross sections. However there is also an interest in determining how expectation values of field operators evolve in time from an initial state. In this paper I will examine some aspects of this problem.

physics.gen-ph↗

Conservative relativity principle: Logical ground and analysis of relevant experiments

We suggest a new relativity principle, which asserts the impossibility to distinguish the state of rest and the state of motion at the constant velocity of a system, if no work is done to the system in question during its motion. We suggest calling this new rule as "conservative relativity principle" (CRP). In the case of an empty space, CRP is reduced to the Einstein special relativity principle. We also show that CRP is compatible with the general relativity principle. One of important implications of CRP is the dependence of the proper time of a charged particle on the electric potential at its location. In the present paper we consider the relevant experimental facts gathered up to now, where the latter effect can be revealed. We show that in atomic physics the introduction of this effect furnishes a better convergence between theory and experiment than that provided by the standard approach. Finally, we reanalyze the Moessbauer experiments in rotating systems and show that the obtained recently puzzling deviation of the relative energy shift between emission and absorption lines from the relativistic prediction can be explained by the CRP.

physics.gen-ph↗

Vanishing Dimensions in Four Dimensional Cosmology with Nonminimal Derivative Coupling of Scalar Field

We discussed a mechanism that allows the universe to start from lower dimension ($d < 4$) in its very early era and evolves to four dimension at the end of the process. The mechanism is generated by a nonminimal derivative coupling of scalar field, where derivative terms of the scalar field coupled to curvature tensor. We solve the Einstein equations for a limit of large and nearly constant Hubble parameter and analyze the evolution of the Hubble parameter in this limit. The lower-dimensionality in early universe has advantages in the context of unification theory.

physics.gen-ph↗

Special relativity as classical kinematics of a particle with the upper bound on its speed. Part II. The general Lorentz transforrmation and the generalized velocity composition theorem

The kinematics of a particle with the upper bound on the particle's speed (a modification of classical kinematics where such a restriction is absent) has been developed in [arXiv:1204.5740]. It was based solely on classical mechanics without employing any concepts , associated with the time dilatation or/and length contraction. It yielded the 1-D Lorentz transformation (LT), free of inconsistencies (inherent in the canonical derivation and interpretations of the LT). Here we apply the same approach to derive the LT for the 3-dimensional motion of a particle and the attendant law of velocity composition. As a result, the infinite set of four-parameter transformations is obtained. The requirement of linearity of these transformations selects out of this set the two-parameter subset . The values of the remaining two parameters ,dictated by physics of the motion, is explicitly determined , yielding the canonical form of the 3-dimensional LT. The generalized law of velocity composition and the attendant invariant ( not postulated apriori) of the motion are derived, As in the one-dimensional case, present derivation, as a whole, does not have any need in introducing the concepts of the time dilatation and length contraction, and is based on the classical concepts of time and space.

physics.gen-ph↗

Multicoloured Random Graphs: The Random Dynamics Program

The Random Dynamics program is a proposal to explain the origin of all symmetries, including Lorentz and gauge invariance without appeal to any fundamental invariance of the laws of nature, and to derive the known physical laws in such a way as to be almost unavoidable. C. D. Froggatt and H. B. Nielsen proposed in their book Origin of Symmetries, that symmetries and physical laws should arise naturally from some essentially random dynamics rather than being postulated to be exact. The most useful assumption of the program that can be made about the fundamental laws is taken to be that they are random and then to see how known physics like mechanics and relativity follow from them. It is believed that almost any model of these regularities would appear in some limit for example as energies become small. Almost all theories or models at the fundamental level could then explain known physics. We suggest how using the formalism and properties of random graphs might be useful in developing the theory, and point towards directions in which it can be more fully extended in future work.

physics.gen-ph↗

The Euclid space-time diagram of the theory of relativity

A conventional space-time diagram is $r-ct$ one, which satisfies the Minkowski geometry. This geometry conflict the intuition from the Euclid geometry. In this work an Euclid space-time diagram is proposed to describe relativistic world lines with an exact Euclid geometry. The relativistic effects such as the dilation of moving clocks, the contraction of moving length, and the twin paradox can be geometrically expressed in the Euclid space-time diagram. It is applied to the case of a satellite clock to correct the gravitational effect. It is found that this Euclid space-time diagram is much more intuitive than the conventional space-time diagram.

physics.gen-ph↗

Can negative mass be considered in General Relativity ?

We show, through Newtonian approximation, that shifting to a bimetric model of the Universe based on a suitable system of coupled field equations, removes the preposterous runaway effect and gives different interaction laws, between positive and negative masses, that bring new insights into the alternative VLS interpretations previously proposed by several authors, and strengthening their assumptions.

physics.gen-ph↗

Derivation of the relativistic momentum and relativistic equation of motion from Newton's second law and Minkowskian space-time geometry

Starting from the classical Newton's second law which, according to our assumption, is valid in any instantaneous inertial rest frame of body that moves in Minkowskian space-time we get the relativistic equation of motion $\vec{F}=d\vec{p}/dt$, where $\vec{p}$ is the relativistic momentum. The relativistic momentum is then derived without referring to any additional assumptions concerning elastic collisions of bodies. Lorentz-invariance of the relativistic law is proved without tensor formalism. Some new method of force transformation is also presented.

physics.gen-ph↗