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Ion Simaciu

Publications and source records attributed to Ion Simaciu.

At least 19 recordsLinked to original sources
arXiv2025

Vacuum permittivity and gravitational refractive index revisited

The present paper reanalyzes the problem of the refractive properties of the physical vacuum and their modification under the action of the gravitational field and the electromagnetic field. This problem was studied in our previous works and in the subsequent works of the researchers: Leuchs, Urban, Mainland and their collaborators. By modeling the physical vacuum as a particle-antiparticle system, we can deduce with a certain approximation, in a semiclassical theory, the properties of the free vacuum and the vacuum modified by the interaction with a gravitational field and an electromagnetic field. More precise calculation of permittivities of free vacuum and near a particle can lead to a non-point model of the particle. This modeling can follow both the quantum and the general relativistic path as well as the phenomenological path, the results complementing each other.

physics.gen-ph↗
arXiv2024

Vortex-bubble system as a spin acoustic particle model

A vortices-bubble system may be depicted by some features which may lead to infer its acoustic charge and its spin angular momentum. We study the dynamics of this system within the framework of fluid physics and with the help of Maxwell's hydrodynamic equations. Since we will adopt an approach of a fluid without viscosity and without gravity, then the fluid is in steady state if also we will neglect the acoustic radiation. When we expressed the energy (the kinetic and potential energy) of the vortex-bubble system we found out that the state of bubble which is captured in the core of the vortex is more stable than it is out of the core. For the above allegations we consider that this system, namely a vortex-bubble system, is a good approach for an acoustic particle with charge and spin angular momentum. This system owns to the Acoustic World.

physics.gen-ph↗
arXiv2024

Vortexes as systems specific to the Acoustic World

In this paper we study the properties of vortexes, as systems specific to the Acoustic World, using both hydrodynamic theory and the corresponding hydrodynamic Maxwell equations. According to this study, it follows that the vortex behaves like an acoustic dipole that has intrinsic/internal angular momentum. The system of two identical vortices also has orbital angular momentum and behaves, at distances much greater than the distance between the axes of the vortices, as a single vortex. With the help of Maxwell's hydrodynamic equations for the vortex we deduced the force between two vortices and obtained the expression of the equivalent mass of the vortex and the permittivity of the electroacoustic field. We also obtained and interpreted the expression for the energy density of the acoustic field. The density and pressure variations induced by the vortex cause the change in the propagation speed of the acoustic waves and the acoustic lensing property of the vortex.

physics.gen-ph↗
arXiv2023

Compatibility of Maxwell's fluid equations with interactions between oscillating bubbles

The outcome of this paper was a shape of the interaction of two oscillating bubbles. This was done to express the secondary Bjerknes force using the Maxwell equations for a liquid. These subsequent equations were written for the quantities velocity, pressure, and density as deviations from steady state. Also, as it will show in the following rows, we found the expressions of the acoustic charge and of the acoustic intensity. Our results may facilitate the adoption of an approach for the interaction of two vortices and for the entrapment of a bubble by a vortex. This approach leads to a model for an acoustic charged particle which has internal angular momentum.

physics.gen-ph↗
arXiv2023

Quantitative analysis of secondary Bjerkenes forces in various liquids

Numerically calculating the interaction forces between two free bubbles under the action of a background of random acoustic radiation, we highlight the contributions of radiative coefficient and absorption damping coefficient to the size of these forces.It is quantitatively demonstrated, for different radii of the oscillating bubbles, that the scattering absorption forces and the scattering scattering forces are close in magnitude.For superfluid helium, the forces change direction, oscillatingly, and the ratio of the forces is much less than one.

physics.gen-ph↗
arXiv2022

Phenomena in bubbles cluster

Following some previous papers, we continue in this paper to give proof of the analogy between the acoustic world and the electromagnetic world. Hence we derive the expressions for: the scattering-scattering force (the electro-acoustic force) between the bubbles found in the inner cluster and the bubble found out of the cluster, the scattering-absorption force (the gravito-acoustic forces) between the bubbles found in the inner cluster, the gravito-acoustic forces between the cluster as a whole and an outer bubble, the temperature corresponding to the translational motion of the bubbles in the inner cluster and the average pressure of the acoustic radiation. The results of our calculus led us to find out that the absolute value of the average pressure of the acoustic radiation around a bubble is equal to the density of the energy of the electro-acoustic field, Eq. (10). This is the most important result of this paper. These densities are the densities of the energy corresponding to the oscillation of the bubble (the liquid around the bubble) that are involved in the interaction phenomenon between two oscillating bubbles. We have also demonstrated that the gravito-acoustic forces, at resonance, between the bubbles inside the cluster, generated by the absorption of energy in the bubbles, are proportional to the square of the virtual masses of the bubbles, Eqs. (29) and (30).

physics.gen-ph↗
arXiv2022

Acoustic gravitational interaction revised

In this paper, we deduce the expression of the gravito-acoustic force between two oscillating bubbles using the hypothesis that this type of force is a force of scattering-absorption of the energy of excitatory waves. The expression of the gravito-acoustic force at resonance highlights the dependence of this force on the product of the virtual masses of the two bubbles and on an acoustic gravitational constant. The acoustic gravitational constant depends on the absorption damping coefficient. We may say also that the expression of the acoustic gravitational constant is analogous to the expression of the gravitational constant in the electromagnetic world, that one obtained in the Einstein-Sciama model and the Dirac-Eddington large numbers hypothesis. The results obtained for this type of phenomenon in the acoustic world support the similarity between the acoustic world and the electromagnetic world.

physics.gen-ph↗
arXiv2021

Electrostatic Interaction in Stochastic Electrodynamics

Assuming the charged particle to be a two-dimensional oscillator that scatters the classical background of zero-point field one can deduce the Coulomb force of the two interacting particles. The correct deduction of the force is conditioned by the equality between the natural angular frequency of the oscillator and the angular frequency of Zitterbewegung.

physics.gen-ph↗
arXiv2021

Gravitational interaction mediated by Classical Zero Point Field

By modeling the particle as a two-dimensional oscillator with the natural angular frequency equal to the Zitterbewegung frequency, the expression of the gravitational force between two particles is obtained. Gravitational force is the effect of the absorption-scattering of the CZPF background by the oscillators. The connection between the gravitational and the electrostatic interaction is obtained.

physics.gen-ph↗
arXiv2020

Dumb Hole Associated with an Oscillating Bubbles Cluster

In this paper, it is shown that in interaction with an oscillating bubbles cluster the fluid becomes inhomogeneous. The radial variation of the acoustic refractive index of the fluid generates an acoustic lens with spherical symmetry. When the focal length of the lens associated with the bubbles cluster is equal to the length of the position vector then the bubbles cluster behaves like a dumb hole. Unlike the properties of a bubble, the cluster, by compression under the action of attractive internal forces, can shrink its radius to become a dumb hole.

physics.flu-dyn↗
arXiv2019

Mach's Principle in the Acoustic World

The aim of this paper is to investigate the coupled oscillations of multiple bubbles within a cluster. The interaction between a bubble and the other bubbles in a cluster produces an additional mass. For a fixed number of bubbles ( ) and uniformly distributed, in case of a certain value of the bubble density, we deduce the relations analogous to the Eddington relation (between the cluster radius and the bubble radius) and the Sciama relation (between the cluster radius and the gravitoacoustic radius) according to Mach's Principle.

physics.gen-ph↗
arXiv2019

Acoustic force of the gravitational type

In this paper it was shown that, under certain restrictive conditions, Bjerknes secondary forces are attractive and proportionate to the product of the virtual masses of the two bubbles.

physics.class-ph↗
arXiv2018

Deviation of the waves in an inhomogeneous medium

Using the formula found by Noorbala and Sepehrinia, the wave deviation in an inhomogeneous medium with continuous variation of propagation velocity is deduced. For electromagnetic waves (light) that propagate in the gravitational field, the deduced deviation is identical to that calculated from General Relativity. The method and its consequences are a good example that verifies the Noorbala-Sepehrinia's formula as well as the mecano-optics analogy (Hamilton's principle / principle of stationary action and Fermat's principle) for the bodies movement in the gravitational field.

physics.gen-ph↗
arXiv2017

Acoustic scattering-extinction cross section and the acoustic force of electrostatic type

The analysis of the secondary Bjerknes force between two bubbles suggests that this force is analogous to the electrostatic forces. The same analogy is suggested by the existence of a scattering cross section of an acoustic wave on a bubble. Our paper brings new arguments in support of this analogy. The study which we perform is dedicated to the acoustic force and to the scattering cross section at resonance in order to highlight their angular frequency independence of the inductor wave. Also, our study reveals that the angular frequency and the amplitude of the induction pressure wave are not related. Highlighting this analogy will allow us a better understanding of the electrostatic interaction if the electron is modeled as an oscillating bubble in the vacuum.

physics.gen-ph↗
arXiv2016

Interactions in an acoustic world

The present paper aims to complete an earlier paper where the acoustic world was introduced. This is accomplished by analyzing the interactions which occur between the inhomogeneities of the acoustic medium, which are induced by the acoustic vibrations traveling in the medium. When a wave packet travels in a medium, the medium becomes inhomogeneous. The spherical wave packet behaves like an acoustic spherical lens for the acoustic plane waves. According to the principle of causality, there is an interaction between the wave and plane wave packet. In specific conditions the wave packet behaves as an acoustic black hole.

physics.gen-ph↗
arXiv2016

Planck-Einstein-de Broglie type relations for the acoustic waves

In this paper we prove, by expressing the energy as a function of the wave propagation speed, it is highlighted the existence of an equivalent mass of the wave, as well as of an Einstein type relations between the energy and this mass. Also, we establish a relation between angular frequency and energy similar to that of the Planck relation. For the propagating wave, there is a de Broglie type relationship between the linear momentum and the action variable (the angular momentum), i.e. the wave linear momentum is proportional to the wave number, the proportionality coefficient being the action.

physics.gen-ph↗
arXiv2015

Planck-Einstein-de Broglie relations for wave packet: the acoustic world

In this paper we study the relations of Planck-Einstein-de Broglie type for the wave packets. We assume that the wave packet is a possible model of particle . When studying the behaviour of the wave packet for standing waves, in relation to an accelerated observer (i.e. Rindler observer), there can be demonstrated that the equivalent mass of the packet is the inertial mass. In our scenario, the waves and of the wave packets are depicted by the strain induced/produced in the medium. The properties of the waves, of the wave packet and, generally, of the perturbations in a material medium suggest the existence of an acoustic world. The acoustic world has mechanical and thermodynamical properties. The perturbations that are generated and propagated in the medium are correlated by means of acoustic waves with maximum speed. The observers of this world of disturbances (namely the acoustic world) have senses that are based on the perception of mechanical waves (disturbance of any kind) and apparatus for detecting and acquiring information by means of the same type of wave. Time and length measurements (and other parameters) are correlated by Lorentz type transformations, where the maximum speed is the speed of the sound waves. By applying these transformations to the packet of standing waves, there results that the energy, mass, linear momentum and the action variable/variable action undergo relativistic changes. We highlight the fact that the dynamic relativist relationship between energy and momentum is a consequence of the wave packet model for a particle. We have also emphasized the existence of certain limits for the energy of the disturbance and the corresponding action variable.

physics.class-ph↗