Newtonian Mass Research Articles

On the Alleged Incommensurability of Newtonian and Relativistic Mass

On the Alleged Incommensurability of Newtonian and Relativistic Mass

MHD nonlinear thermally radiative Ag − TiO 2/H 2 O hybrid nanofluid flow over a stretching cylinder with Newtonian heating and activation energy

Hybrid nanofluids are significant in biomedical, industrial, transportation, as well as several engineering applications due to their high thermal conductivity and mass transfer enhancement nature in contrast to regular fluids and nanofluids. Taking this into consideration, the present problem explores the flow of hybrid nanofluid (Ag − TiO 2/H 2 O) over a stretching cylinder subject to Newtonian heat and mass conditions. The novel aspect of the current work is to analyze the heat and mass transfer characteristics of MHD hybrid nanofluid flow on Darcy-Forchheimer porous medium in addition to activation energy, nonlinear thermal radiation, heat generation/absorption, viscous and Joulian dissipation. Further, Silver (Ag) and Titanium oxide (TiO 2) are the constituent nanoparticles of the water-based hybrid nanofluid owing to their stable chemical features and extensive industrial manufacturing. By introducing suitable similarity transformations, the governing partial differential equations (PDEs) of the developed model are reduced to ordinary differential equations (ODEs), and then the numerical solution is procured with shooting technique by using MATLAB solver bvp4c. The influence of the pertinent parameters is depicted graphically and described elaborately. The analysis indicates that velocity exhibits a declining trend against the permeability and Forchheimer parameters, while the temperature profiles show opposite behavior. The radiation and conjugate heat parameters (R, γ 1) upgrade the heat transfer rate, while the curvature and conjugate mass parameters (α c , γ 2) amplify the mass transfer rate. The maximum heat transfer rate of Ag − TiO 2/H 2 O hybrid nanofluid is 2.3344 attained for γ 1 = 0.6. The investigation demonstrates larger heat and mass transfer rates for Ag − TiO 2/H 2 O hybrid nanofluid than Ag − H 2 O nanofluid. The outcomes of the present investigation have practical applications in conjugate heat transfer over fins, development of vaccines, effluent treatment plants, solar cells, heat exchangers, and many more. An excellent agreement is achieved on comparing our numerical results with the published results in the literature.

Influence of heat flow due to concentration gradient on unsteady MHD heat and mass transform dissipative flow with spanwise fluctuating temperature

This study investigates the influence of heat flow due to a concentration gradient on unsteady Newtonian free convective magnetohydrodynamic heat and mass transform dissipative fluid flow over a heated normal porous plate in the presence of radiation absorption and chemical reaction. The plate temperature is assumed to fluctuate in a spanwise cosinusoidal manner over a time and exhibit heat generation with suction velocity. The analysis employs the multiple regular perturbation method to evaluate the governing equations under stipulated boundary conditions. The outcomes are visually depicted to assess the impact of various parameters on the system dynamics. Graphical representations illustrate the physical significance of various parameters on velocity, temperature, and concentration. Additionally, skin friction, mass transfer rate, and heat transfer coefficients are presented in tabular form. The significant findings indicate that velocity, temperature, and skin friction are directly proportional to parameters such as radiation absorption, heat generation, and heat flux due to a chemical potential gradient, whereas Sherwood and concentration are inversely proportional to the Schmidt number and chemical reaction. The outcomes obtained in this study have been cross-referenced with existing scientific literature, demonstrating strong concordance. This alignment provides confidence in the numerical results.

Impact of thermal diffusion and diffusion-thermal effects on MHD Maxwell fluid subject to Newtonian heat and mass conditions over a stretching cylinder

Current research's main focus is to incorporate the novel idea of Newtonian flux condition in MHD stretching flow of Maxwell liquid with Stefan blowing. An analysis is done to explore the heat and mass transfer characteristics of MHD Maxwell fluid towards a stretching cylinder, including thermal diffusion and diffusion-thermal energy implications in the presence of activation energy. Polar coordinates (z, r) in the shape of a cylinder are used to model the issue. To convert controlling PDEs into ODEs, similarity the variables are used. The governing equations of motion that result are tackled via the notorious R-K 4th order approach. Through graphical portrayal, the impacts of various factors, including curvature, magnetics, Stefan blowing, reaction, and activation energy parameters, are studied. Furthermore, the validation of numerical findings is prepared by benchmarking with previously determined limiting conditions, and we launch a wonderful communication with these results.

Air pollution and topography in Tehran

Tehran is one of the most polluted cities in the world with 48 days of air pollution exceeding the admissible threshold (AQI > 150) for 3 months of the 15 years studied. This period coincides with the time when Tehran’s inversion reaches its maximum stability. The purpose of this study was to determine the height of air pollution in Tehran in the days when pollution exceeds the permissible limit. Continuing to study the pressure and temperature conditions of these days, we then considered the geographical and topographic conditions, and finally identified the best of these cells for potential theoretical air turbulence. The results of this study, based on the Harmonic Analysis method and based on Tehran temperature and pressure data over a 15-year period (2003–2017), show that the highest elevation of Tehran inversion does not exceed 1800 m on polluted days. Only within 6 days of those beyond the admissible threshold, temperature and pressure cells with the highest Newtonian mass are formed. The center of these cells formed with a compressive difference of 32 mg in November, 7 mg in January, 11 mg in December, and temperature difference of 1.1° in November, 4.4° in January, and 1.9° in December. Generally, we considered the formed cells by the temperature and pressure difference and the gradient between them, as well as the difference in height between the cells and their location. This information, combined with the local winds causing the differences in temperature and pressure, allows us to elucidate conditions for creating air turbulence in Tehran and mitigating the amount and degree of air pollution.

Uncertainty of Low‐Degree Space Gravimetry Observations: Surface Processes Versus Earth's Core Signal

AbstractSpace gravity measurements have been mainly used to study the temporal mass variations at the Earth's surface and within the mantle. Nevertheless, mass variations due to the Earth's core might be observable in the gravity field variations as measured by Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow‐On satellites. Earth's core dynamical processes inferred from geomagnetic field measurements are characterized by large‐scale patterns associated with low spherical harmonic degrees of the potential fields. To study these processes, the use of large spatial and inter‐annual temporal filters is needed. To access gravity variations related to the Earth's core, surface effects must be corrected, including hydrological, oceanic or atmospheric loading (Newtonian attraction and mass redistribution). However, these corrections for surface processes add errors to the estimates of the residual gravity field variations enclosing deep Earth's signals. As our goal is to evaluate the possibility to detect signals of core origin embedded in the residual gravity field variations, a quantification of the uncertainty associated with gravity field products and geophysical models used to minimize the surface process signatures is necessary. Here, we estimate the dispersion for GRACE solutions as about 0.34 cm of equivalent water height (EWH) or 20% of the total signal. Uncertainty for hydrological models is as large as 0.89–2.10 cm of EWH. We provide estimates of Earth's core signals whose amplitudes are compared with GRACE gravity field residuals and uncertainties. The results presented here underline how challenging is to get new information about the dynamics of the Earth's core via high‐resolution, high‐accuracy gravity data.

Quantum origin of (Newtonian) mass and Galilean relativity symmetry

Quantum origin of (Newtonian) mass and Galilean relativity symmetry

Maximum mass of relativistic self-gravitating Bose-Einstein condensates with repulsive or attractive |φ|4 self-interaction

We derive an approximate analytical expression of the maximum mass of relativistic self-gravitating Bose-Einstein condensates with repulsive or attractive $|\ensuremath{\varphi}{|}^{4}$ self-interaction. This expression interpolates between the general relativistic maximum mass of noninteracting bosons stars, the general relativistic maximum mass of bosons stars with a repulsive self-interaction in the Thomas-Fermi limit, and the Newtonian maximum mass of dilute axion stars with an attractive self-interaction [P. H. Chavanis, Phys. Rev. D 84, 043531 (2011)]. We obtain the general structure of our formula from simple considerations and determine the numerical coefficients in order to recover the exact asymptotic expressions of the maximum mass in particular limits. As a result, our formula should provide a relevant approximation of the maximum mass of relativistic boson stars for any value (positive and negative) of the self-interaction parameter. We discuss the evolution of the system above the maximum mass and consider application of our results to dark matter halos and inflaton clusters. We also make a short review of boson stars and Bose-Einstein condensate dark matter halos and point out analogies with models of extended elementary particles.

Oblique rotational dynamics of chemically reacting tri-hybridized nanofluids over a suddenly moved plate subject to Hall and ion slip currents, Newtonian heating and mass fluxes

The hydro-thermodynamical performance and efficiency of exceedingly sensitive systems is a significant issue in many engineering and scientific processes in the present day. Nanomaterials that have undergone hybridization exhibit novel properties that make them useful in various engineering contexts. Compared to hybridized nanofluid (HNF) and nanofluid (NF), a tri-hybridized nanofluid (THNF) is a novel concept in the field of investigation that provides a more efficient rate of heat transmission. Impelled by these, we quest to explore the dynamism of a non-Newtonian water-ethylene glycol mixture (vol.60–40 %) based tri-hybridized nanofluid (Cu–Ti O2-A l2O3/WEG) on an oblique plate with ramped motion in the attendance of Hall and ion-slip currents, Darcy's porous resistance, heat radiation, chemical reaction, Newtonian heat and mass fluxes in a magneto-rotating environment. The partial differential equations (PDEs) portraying the physical problem are set up via physical hypotheses and constraints. The subsequently obtained non-dimensional PDEs are unsteady, addressed by the Laplace transform method analytically. The physical effects of significant emergent factors, the accompanying flow patterns, and the assessment of industrial relevance are executed and thoroughly explained using a variety of graphics and tables. Our analysis proves a sharp upsurge in the resultant velocity over higher variations of Hall and ion-slip parameters. Increasing estimations of chemical reacting factor and NPs' volume fractions significantly deteriorate the mass transfer rate, while reversal conduct is prevailed due to Newtonian mass flux. Additionally, comparatively lower mass transmission for tri-hybridized nanofluid is documented than hybridized nanofluid. Our modelling could be applicable in industrial processes, dynamics of nano-polymers, hybrid nano-lubricants used in heat management systems, etc.

Bioconvective unsteady fluid flow across concentric stretching cylinders with thermal-diffusion and diffusion-thermo effects

The current study emphasizes bioconvective viscous fluid flow between two horizontal deformable cylinders. At the cylindrical walls, the Newtonian heat and mass condition with velocity slip is examined. The thermal and solutal transfer is optimized by amalgamating Soret–Dufour effects with variable heat source/sink. The equations that regulate the flow are simplified via appropriate transformations. The bvp4c algorithm is employed to obtain the numerical solution. The ramifications of the emerging parameters are portrayed graphically. Numerical values for drag force coefficient, heat flux, mass flux, and local motile density numbers are enumerated in tabulated form. Axial velocity accelerates on varying the unsteadiness parameter. The thermal field elevates by augmenting the Dufour number and thermal conjugate parameter. The drag force coefficient exhibits a decreasing behavior on enhancing the unsteadiness and velocity slip parameters. An opposite behavior is exhibited by heat and mass flux on amplifying the Soret and Dufour number. Motile density deteriorates on elevating the Lewis number and unsteadiness parameter. A substantial correlation has been noticed by graphically comparing the results of this study with the previous literature.

Subsonic wind accretion

ABSTRACT The rate of subsonic wind accretion (accretion on a point Newtonian mass moving through uniform gas) is shown to be independent of the wind velocity and equal to the spherical Bondi rate – for the adiabatic index equal to 5/3. A (very accurate) numerical calculation of the accretion flow, confirming this result, is also presented.

Fractional Model and Exact Solutions of Convection Flow of an Incompressible Viscous Fluid under the Newtonian Heating and Mass Diffusion

In this paper, we consider a natural convection flow of an incompressible viscous fluid subject to Newtonian heating and constant mass diffusion. The proposed model has been described by the Caputo fractional operator. The used derivative is compatible with physical initial and boundaries conditions. The exact analytical solutions of the proposed model have been provided using the Laplace transform method. The obtained solutions are expressed using some special functions as the Gaussian error function, Mittag–Leffler function, Wright function, and G‐function. The influences of the order of the fractional operator, parameters used in modeling the considered fluid, Nusselt number, and Sherwood number have been analyzed and discussed. The physical interpretations of the influences of the parameters of our fluid model have been presented and analyzed as well. We use the graphical representations of the exact solutions of the model to support the findings of the paper.

ANALYZING THE EFFECTIVENESS OF HYDROMAGNETIC FLUX OF CASSON NANOFLUID IN A POROUS SHEET UNDER NEWTONIAN MASS AND HEAT TRANSFER CONDITIONS

ANALYZING THE EFFECTIVENESS OF HYDROMAGNETIC FLUX OF CASSON NANOFLUID IN A POROUS SHEET UNDER NEWTONIAN MASS AND HEAT TRANSFER CONDITIONS

The MHD Newtonian hybrid nanofluid flow and mass transfer analysis due to super-linear stretching sheet embedded in porous medium

The steady magnetohydrodynamics (MHD) incompressible hybrid nanofluid flow and mass transfer due to porous stretching surface with quadratic velocity is investigated in the presence of mass transpiration and chemical reaction. The basic laminar boundary layer equations for momentum and mass transfer, which are non-linear partial differential equations, are converted into non-linear ordinary differential equations by means of similarity transformation. The mass equation in the presence of chemical reaction is a differential equation with variable coefficients, which is transformed to a confluent hypergeometric differential equation. The mass transfer is analyzed for two different boundary conditions of concentration field that are prescribed surface concentration (PSC) and prescribed mass flux (PMF). The asymptotic solution of concentration filed for large Schmidt number is analyzed using Wentzel-Kramer-Brillouin (WKB) method. The parameters influence the flow are suction/injection, superlinear stretching parameter, porosity, magnetic parameter, hybrid nanofluid terms, Brinkman ratio and the effect of these are analysed using graphs.

Meta-mass systems: A harbinger for a vibration energy harvesting technology

For a limited class of fuzzy structures, the “master” structure is a grounded Newtonian mass wherein are distributed the “fuzzies,” modeled as nearly equal magnitude sprung masses with resonances densely filling a frequency band. We term said system a grounded “meta-mass,” showing a properly designed “meta-mass vibration energy harvester” addresses a fundamental technical obstacle to the harvesting of waste mechanical energy, the so-called “aperture” problem; thereby making meta-mass systems a harbinger for a vibration energy harvesting technology. Shown is the oscillators’ resonances provide ``bounds’’ on the system resonances, the relative “locations” of the system resonances within its bound-pair being determinative of system behavior. Then shown is the value of a certain combination of non-dimensional system measures—twice the fractional bandwidth squared divided by the product of the mass ratio and the natural log of N—is determinative of said relative locations. Finally shown is virtually all the energy inputted impulsively to the Newtonian mass is transferred to the encapsulated oscillators in a time of the order of the inverse of the band of oscillators, for a narrow system subclass wherefore each system resonance is near the center of its bound-pair.

Nontopological chiral chemical potential due to the Zeeman field in magnetic Weyl semimetals

As condensed-matter manifestations of the chiral anomaly, the coexistence of positive longitudinal magnetoconductivity (LMC) and the planar Hall effect (PHE) is regarded as a characteristic transport signal for the Weyl semimetal (WSM) phase. By including a finite Newtonian mass into the general linearized WSM model, we derive an analytical expression for the chiral chemical potential, which includes a topological term of the chiral anomaly and a nontopological term. The nontopological term stems from the Zeeman-field-induced tilt of the Weyl cones, which breaks the symmetry of the fermion filling between the Weyl valleys of opposite chiralities and further leads to a chiral chemical potential $\ensuremath{\propto}\mathbit{E}\ifmmode\cdot\else\textperiodcentered\fi{}\mathbit{B}$, much as the effect of the chiral anomaly. We demonstrate that the resulting LMC is positive and can coexist with the PHE without invoking the mechanism of the chiral anomaly. Hence, the chiral chemical potential might not be exclusively respected to the chiral anomaly. Experimentally, one can distinguish the chiral anomaly from the proposed tilt mechanism by inspecting the dependence of magnetoconductivity on the Fermi energy.

Gravitational partition function modified by superlight braneworld perturbative modes

In this paper, we will analyze the effects of super-light brane world perturbative modes on clustering of galaxies. In present manuscript, we use the Boltzmann and Tsallis statistical approaches to study the large distance modification of gravity in the brane world. The impact of modified potential on clustering of galaxies is analyzed in both the approaches. The infinities associated with Newtonian point mass approximation of gravity models is removed using the analytical extensions. The regularized and finite partition function is obtained for the system of galaxies in the brane world model and is used to evaluate the regularized thermodynamic properties of the system in the form of equations of state. Hence, we study thermodynamic quantities and discuss about the thermodynamic stability of the model. We find that large number of galaxies may lead to the thermodynamic instability.

Radiation Effect on Unsteady Free Convection and Mass Transfer Flow Between Two Vertical Parallel Plates with Newtonian Heating

The purpose of this study is to investigate analytically free convection flow between two vertical parallel plates with Newtonian heating and mass diffusion. Radiation also taken into consideration. Appropriate non-dimensional variables are used to transform the dimensional governing equations. The velocity, temperature and concentration profiles are solved analytically using Laplace Transform technique. The corresponding expressions for skin friction and Nusselt number are also calculated. The graphical results are displayed to illustrate the influence of Newtonian heating parameter, thermal radiation parameter, Prandtl number and Schmidt number. The effect of Newtonian heating parameter is observed whereby it increases the Nusselt number but decreases the skin friction. Results also shown that, Nusselt number decreases when radiation increases meanwhile skin friction decreases when radiation parameter increases.

Eccentric-orbit extreme-mass-ratio-inspiral radiation. II. 1PN correction to leading-logarithm and subleading-logarithm flux sequences and the entire perturbative 4PN flux

In a recent paper we showed that for eccentric-orbit extreme-mass-ratio inspirals the analytic forms of the leading-logarithm energy and angular momentum post-Newtonian (PN) flux terms (radiated to infinity) can, to arbitrary PN order, be determined by sums over the Fourier spectrum of the Newtonian quadrupole moment. We further showed that an essential part of the eccentricity dependence of the related subleading-logarithm PN sequences, at lowest order in the symmetric mass ratio $\nu$, stems as well from the Newtonian quadrupole moment. Once that part is factored out, the remaining eccentricity dependence is more easily determined by black hole perturbation theory. In this paper we show how the sequences that are the 1PN corrections to the entire leading-logarithm series, namely terms that appear at PN orders $x^{3k+1} \log^k(x)$ and $x^{3k+5/2} \log^k(x)$ (for PN compactness parameter $x$ and integers $k\ge 0$), at lowest order in $\nu$, are determined by the Fourier spectra of the Newtonian mass octupole, Newtonian current quadrupole, and 1PN part of the mass quadrupole moments. We also develop a conjectured (but plausible) form for 1PN correction to the leading logs at second order in $\nu$. Further, in analogy to the first paper, we show that these same source multipole moments also yield nontrivial parts of the 1PN correction to the subleading-logarithm series, and that the remaining eccentricity dependence (at lowest order in $\nu$) can then more easily be determined using black hole perturbation theory. We use this method to determine the entire analytic eccentricity dependence of the perturbative (i.e., lowest order in $\nu$) 4PN non-log terms, $\mathcal{R}_4(e_t)$ and $\mathcal{Z}_4(e_t)$, for energy and angular momentum respectively.

Momentum-dependent mass and AC Hall conductivity of quantum anomalous Hall insulators and their relation to the parity anomaly

The Dirac mass of a two-dimensional QAH insulator is directly related to the parity anomaly of planar quantum electrodynamics, as shown initially in Phys. Rev. Lett. 52, 18 (1984). In this work, we connect the additional momentum-dependent Newtonian mass term of a QAH insulator to the parity anomaly. By calculating the effective action, we reveal that the Newtonian mass term acts like a parity-breaking element of a high-energy regularization scheme. As such, it is directly related to the parity anomaly. In addition, the calculation of the effective action allows us to determine the finite frequency correction to the DC Hall conductivity of a QAH insulator. We derive that the leading order AC correction contains a term proportional to the torsional Hall viscosity. This paves the way to measure this non-dissipative transport coefficient via electrical or magneto-optical experiments. Moreover, we prove that the Newtonian mass significantly changes the resonance structure of the AC Hall conductivity in comparison to pure Dirac systems like graphene.