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At least 919 records · Page 51Linked to original sources
arXiv2012

On the Majorana equation - Relations between its complex two-component and real four-component eigenfunctions

We first derive without recourse to the Dirac equation the two-component Majorana equation with a mass term by a direct linearization of the relativistic dispersion relation of a massive particle. Thereby, we make only use of the complex conjugation operator and the Pauli spin matrices, corresponding to the irreducible representation of the Lorentz group. Then we derive the complex two-component eigenfunctions of the Majorana equation and the related quantum fields in a concise way, by exploiting the so called chirality conjugation operator that involves the spin-flip operator. Subsequently, the four-component spinor solutions of the real Majorana equation are derived, and their intrinsic relations with the spinors of the complex two-component version of the Majorana equation are revealed and discussed extensively.

physics.gen-ph↗
arXiv2013

Muon-proton Scattering

A recent proposal to measure the proton form factor by means of muon-proton scattering will use muons which are not ultrarelativistic (and also not nonrelativistic). The usual equations describing the scattering cross section use the approximation that the scattered lepton (usually an electron) is ultrarelativistic, with v/c approximately equal to 1. Here the cross section is calculated for all values of the energy. It agrees with the standard result in the appropriate limit.

physics.gen-ph↗
arXiv2012

The substructure of a Quantum Oscillator field

An oscillator (IQuO) more elementary than the quantum one is formulated. This is expressed by quantum operators (a, a+), with two-components and it is composed of sub-oscillators, each with "semi-quanta" (1/2h). The commutation relation of the (a,a+) "semi-quanta" operators is then calculated and the structure by IQuO of the scalar fields is defined with and without electric charge. Processing a coupling mechanism of electrically neutral IQuO that produces a pair (matter-antimatter) with electric charge and not. Through the IQuO-structure it is possible to interpret the electric charge and the isospin (in hadrons) as rotations in an inside space in the particle. Finally, a sub-structure of the quarks is conjectured and one define in probabilistic terms the non-integer value of their electrical charge.

physics.gen-ph↗
arXiv2012

A Superspace Formulation of the BV Action for Higher Derivative Gravity

In this paper we analyse perturbative higher derivative gravity which is known to possess a BRST symmetry associated with its higher derivative structure. We first analyse the anti-BRST and double BRST symmetries of this theory. We then discuss the extended BRST and extended anti-BRST symmetries of this theory using the superspace formalism. We show that even though this theory is generally invariant under extended BRST transformations under extended anti-BRST transformations it is only invariant on-shell.

physics.gen-ph↗
arXiv2012

A Superspace Formulation of the BV Action for Higher Derivative Gauge Theories

In this paper we analyse a certain type of higher derivative gauge theories which are known to possess BRST symmetry associated with their higher derivative structure. We first show that these theories are also invariant under a anti-BRST symmetry and a double BRST symmetry. We then discuss the invariance of these theories under shift symmetry in the superspace Batalin Vilkovisky (BV) formalism. We show that these theories are manifestly extended BRST invariant. However they are only extended anti-BRST invariant on-shell.

physics.gen-ph↗
arXiv2014

Théorie des champs des contraintes et déformations en relativité générale et expansion cosmologique: Theory of stress and strain fields in general relativity and cosmological expansion

In this article we propose to add stress-energy tensor to the Einstein equations, assuming that the matter-energy and the metric space-time is nothing but a continuous medium with some elastic properties. We first give a general expression of the stress tensor which is linearly related to the strain tensor. Then, we give the particular expression of the stress tensor for a spatially homnogeneous and isotropic cosmological medium. After that we derive the modified Friedmann equations. In first approximation, we end up with the usual term $Λg_{μν}$ , where the cosmological constant $Λ=K\varepsilon$ is related with the bulk modulus K and the relative variation of volume (dilatation). Then we derive corrections to the standard model in second approximation, which depend on these two new parameters.

gr-qc↗
arXiv2012

Approaching the event horizon of a black hole

It is argued that it takes an infinite amount of external time for a freely falling test particle to reach the event horizon of a classical black hole (which happens in finite faller time), and that in this time the black hole would have evaporated due to Hawking radiation; so the freely falling test particle would itself evaporate at the event horizon, and so not pass through.

physics.gen-ph↗
arXiv2012

Matter: Space without Time

While Quantum Gravity remains elusive and Quantum Field Theory retains the interpretational difficulties of Quantum Mechanics, we have introduced an alternate approach to the unification of particles, fields, space and time, suggesting that the concept of matter as space without time provides a framework which unifies matter with spacetime and in which we anticipate the development of complete theories (ideally a single unified theory) describing observed 'particles, charges, fields and forces' solely with the geometry of our matter-space-time universe.

physics.gen-ph↗
arXiv2013

Potential Theory in Classical Electrodynamics

In Maxwell's classical theory of electrodynamics the fields are frequently expressed by potentials in order to facilitate the solution of the first order system of equations. This method obscures, however, that there exists an inconsistency between Faraday's law of induction and Maxwell's flux law. As a consequence of this internal contradiction there is neither gauge invariance, nor exist unique solutions in general. It is also demonstrated that inhomogeneous wave equations cannot be solved by retarded integrals.

physics.gen-ph↗
arXiv2012

Quantum Process in Living Cells

Quantum processes have been confirmed for various biological phenomena. Here we model a quantum process in cells based on coherent waves of established ultrafast energy transfers in water. We compute wave speed, ~156 km/s, and wavelength, ~9.3 nm, and determine that the waves retain local coherence. The model is compared with observations and diverse numerical applications lend support to the hypothesis that rapid energy transfers in water are characteristic of living cells. Close agreements are found for the dipole moment of water dimers, microwave radiation on yeast, and the Kleiber law of metabolic rates. We find a sphere with diameter ~20 nm is a lower bound for life in this theory. The quantum properties of the model suggest that cellular chemistry favors reactions that support perpetuation of the energy waves

physics.gen-ph↗
arXiv2021

Electrodynamics without Lorentz force

This communication is devoted to a brief historical framework and to a comprehensive critical discussion concerning foundational issues of Electrodynamics. Attention is especially focused on the events which, about the end of XIX century, led to the notion of Lorentz force, still today ubiquitous in literature on Electrodynamics. Is this a noteworthy instance of a rule which, generated by an improper simplification of Maxwell-JJ Thomson formulation, is in fact physically untenable but, this notwithstanding, highly successful. Modelling of electromagnetic fields and fluxes in spacetime respectively as even and odd spatial differential forms and the formulation of induction laws by means of exterior and Lie derivatives, make their covariance manifest under any smooth spacetime transformations, contrary to the usual affirmation in literature which confines this property to relativistic frame-changes. A remarkable consequence is that there is no entanglement between electric and magnetic fields and fluxes under special relativity transformations. In particular, relativistic support to Lorentz force rule is thus deactivated. For translational motions of charged bodies immersed in a uniform and constant magnetic field, the induced electric field in such a frame, is equal to one half the Lorentz force term. The qualitative successful application of the Lorentz force rule to experimental evidence of special observers is therefore explained.

physics.gen-ph↗
arXiv2013

The role of the $CP(N-1)$ geometry in the intrinsic unification of the general relativity and QFT

Einstein's program of the unified field theory transformed nowadays to the TOE requiring new primordial elements and relations between them. Definitely, they must be elements of the quantum nature. One of most fundamental quantum elements are pure quantum states. Their basic relations are defined by the geometry of the complex projective Hilbert space. In the framework of such geometry all physical concepts should be formulated and derived in the natural way. Analysis following this logic shows that inertia and inertial forces are originated not in space-time but it the space of quantum states since they are generated by the deformation of quantum states as a reaction on an external interaction or self-interaction. In particular, inertia law generalized by Einstein during development of general relativity (GR) will be expressed in intrinsic quantum terms. It is assumed that quantum formulation of the inertia law should clarify the old problem of inertial mass (dynamical mass generation). The conservation of energy-momentum following form this law has been applied to self-interacting quantum Dirac's electron.

physics.gen-ph↗
arXiv2012

Born-Infeld type modification of the gravity

We study a non-linear modification to General Relativity in which the standard Einstein-Hilbert action is replaced by a Born-Infeld type action. Also study us stability issues to judge about viability of this modification. We establish the conditions that this modification must satisfy for to avoid the problems associated with the Dolgov-Kawasaki instability, tachyon instability and negative effective gravitational coupling. The particle content of gravitational spectrum of the linearized Born-Infeld theory shows the existence of massless gravitons plus new degree of freedom of 0-spin associated with $R^2$ term. For a toy model we proved that for appropriate values of the background curvature, this theory is free of ghost, Dolgov-Kawasaki instability and tachyon instability also it has a positive effective gravitational coupling. We find the scalar-tensor theory equivalent at this $f(R)$-theory in the Einstein frame, and we study some properties of the scalar potential.

physics.gen-ph↗
arXiv2014

An algebraic approach to systems with dynamical constraints

Constraints imposed directly on accelerations of the system leading to the relation of constants of motion with appropriate local projectors occurring in the derived equations are considered. In this way a generalization of the Noether's theorem is obtained and constraints are also considered in the phase space.

physics.gen-ph↗
arXiv2013

On the structure of the new particle at 126 GeV (Higgs- or not Higgs-boson?)

A new particle - discovered recently with the Atlas and CMS detectors at LHC - has been interpreted as the long sought Higgs-boson. A corresponding scalar field is needed to make the weak interaction gauge invariant and to understand the quark masses in the Standard Model. However, the Standard Model is an effective theory with quark masses, which can be understood only in a fundamental theory. Such a theory has been constructed, based on a generalised second order extension of QED, in which the quarks can be understood as effective fermions with masses given by binding energies in a boson-exchange potential. In the present approach the Higgs-mechanism is not needed. In this framework a good understanding of particles in the "top" regime is obtained. Two J^π=1^- q-qbar states are predicted, identified with Z(91.2 GeV) and the t-tbar state at about 350 GeV. Further, two 0^+ q-qbar states are obtained, one with a mass consistent with that of the new particle, the other with a mass of about 41 GeV. A detection of the second scalar state will serve as a crucial test of the present model.

physics.gen-ph↗
arXiv2026

A Yang-Mills Type Gauge Theory of Gravity and the Dark Matter Problem

A Yang-Mills type gauge theory of gravity is shown to have a structure richer than that of Einstein's General Theory of Relativity. By elevating the full connections to independent dynamical gauge fields, the theory admits non-trivial vacuum configurations driven by gauge field self-interactions. We demonstrate that this non-linear geometric structure naturally yields an effective spacetime that explains the form of the galactic rotation curves and the anomalous amount of intergalactic gravitational lensing, completely circumventing the need for exotic dark matter particles.

physics.gen-ph↗
arXiv2012

Jets and Accretion Disks in Astrophysics - A Brief Review

The significance of jets and accretion disks in Astrophysics may be growing far beyond any single example of recent finds in the scientific journals. This brief review will summarize recent, significant manifestations of accretion disk powered jets in the universe. We then introduce supplemental contemporary finds in physics and astrophysics which might bear tangential or direct implications for astrophysics toward rethinking the universe with a major role of relativistic jets powered by accretion disks. We conclude with the direction our research will take in order to establish a new perspective on the universe.

physics.gen-ph↗