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In general relativity, the energy density of the gravitational field is not well defined. However, for asymptotically flat spacetimes, various definitions for total mass of the system have been proposed. In this paper, eight masses are considered and it is shown that some of them correspond to the active gravitational mass while the others correspond to the inertial mass. For example, the ADM mass corresponds to the inertial mass, while the Møller mass corresponds to the active gravitational mass. In general, the inertial and active gravitational masses are not equal. If the spacetime is vacuum at large r, the Einstein equations force the inertial and active gravitational masses to be the same. The Einstein equations also force these masses to be the same if any matter that extends out to large r satisfies the weak, strong, or dominant energy condition. The contributions of the inertial and active gravitational masses to the gravitational redshift, the deflection of light, the Shapiro time delay, the precession of perihelia, and the motion of test bodies in the spacetime are also examined.

This paper proposes a new theory of gravity based on aether destruction. In the case of the earth, aether is destroyed within the earth. Aether then accelerates into the earth in an attempt to keep the aether pressure in the earth constant. Any object caught in the accelerating aether flow will be accelerated in the direction of the accelerating aether flow. We suggest a mathematical model to demonstrate that there is a correlation between the aether acceleration and the force of gravity. The mathematical model assumes a porous-like atomic nucleus, in which the nucleons are fixed in position, and a fluid-like aether that can infiltrate between the nucleons but is excluded from their interiors. This theory of gravity assumes that the aether particle interactions are perfectly elastic, and aether can easily penetrate the nucleus of atoms, as they are not affected by electromagnetic or nuclear forces. The effect of gravity is almost entirely due to the fact that aether cannot penetrate the interior of nucleons. We offer a new model of the aether, which includes some new and important concepts that are essential to explain the cause and effect of gravity. The reason why all objects fall at the same speed is explained, and the possible causes for the destruction of the aether are discussed. Since the aether destruction is proportional to the mass of the earth and is, therefore, a cubic relationship, the effect of the accelerating aether flow (gravity) on an object caught in the accelerating aether flow depends on the surface area of the nucleons making up the object and is a square relationship, clarifying, thus, the dilemma cubic or square relationship.

In this paper, we explicitly calculate the aether-like corrections for the electromagnetic field in the case when the space-time involves an extra compact spatial dimension besides of usual four dimensions. Our methodology is based on an explicit summation over the Kaluza-Klein tower of fields which turns out to be no more difficult than the finite-temperature calculations. We found some new terms which can be treated as certain five-dimensional generalizations of the aether-like terms $\kappa^{mnpq}F_{mn}F_{pq}$ and $\bar{\psi}c^{mn}\gamma_m\partial_n\psi$ which in four dimensions are treated as important ingredients of the Lorentz-breaking extension of the standard model. We have shown that these new terms become to dominate in the limit where the extra dimension is very small, allowing us to suggest that there will be essential modifications of quantum corrections if our space indeed has a small extra spatial dimension. Moreover, we have shown that in the CPT-even case we have extra new particles as a consequence of the extra dimension., Comment: 17 pages, matches published version

We provide a uniform treatment of electromagnetic and gravitational memory effects, based on the gravito-electromagnetic formulation of GR and a generalization of the geodesic deviation equation. This allows us to find novel results: in gauge theory, we derive relativistic corrections to the well-known kick memory observable, and a general expression for the displacement memory observable, typically overlooked in the literature. In GR, we find relativistic corrections to displacement and kick memory observables. In both theories, we find novel radial memory effects. Next, we show that electromagnetic and gravitational memory observables can be formulated in terms of certain holonomies on a holographic screen in asymptotically flat spacetimes. In gauge theory, the displacement and kick memory effects form a Hamiltonian vector field which is canonically generated by a Wilson loop. In the first order formulation of GR, we show that the holonomy naturally splits into translational and Lorentz parts. While the former encodes the leading and subleading displacement and kick memory observables, the latter reproduces the gyroscopic memory effect., Comment: 17 pages, 2 figures, Major revision of v3, including relativistic corrections to displacement and kick memory effects

We adapt the post-Newtonian gravitational-radiation methods developed within general relativity by Epstein and Wagoner to the gravitation theory with torsion, recently proposed by Hehl et al., and show that the two theories predict in this approximation the same gravitational radiation losses. Since they agree also on the first post-Newtonian level, they are at the present time - observationally - indistinguishable., Published version: General Relativity and Gravitation, Vol. 12 (1980) 951-961 doi: 10.1007/BF00757366 arXiv-ed February 1980; LaTeX-ed May 1, 2023

Acoustic black hole is becoming an attractive topic in recent years, for it open-up new direction for experimental / observational explorations of black holes. In this work, the gravitational bending of acoustic Schwarzschild black hole is investigated. The gravitational deflection angle of particles traveling along null geodesics, weak gravitational lensing and Einstein ring for acoustic Schwarzschild black hole are carefully studied and analyzed. Particularly, in the calculation of gravitational deflection angle, we resort to two approaches -- the Gauss-Bonnet theorem and the geodesic method. The results show that the gravitational bending effect in acoustic Schwarzschild black hole is enhanced, compared with conventional Schwarzschild black hole. This result indicates that the acoustic black holes may be more easily detectable in gravitational bending effects and weak gravitational lensing observations., Comment: 21 pages, 5 figures, 2 appendices, 2 tables; V2 is minor revision; V3 is major revision; V4: minor revision (astrophysical motivation is included and small errors are corrected) V5: accepted version

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., Comment: 13 pages

The Fermi paradox has given rise to various attempts to explain why no evidence of extraterrestrial civilisations was found so far on Earth and in our Solar System. Here, we present a dynamical model for the development of such civilisations, which accounts for self-destruction, colonisation and astrophysical destruction mechanisms of civilisations including gamma-ray bursts, type Ia and type II supernovae as well as radiation from the supermassive black hole. We adopt conservative estimates regarding the efficiency of such processes and find that astrophysical effects can influence the development of intelligent civilisations and change the number of systems with such civilisations by roughly a factor of 2; potentially more if the feedback is enhanced. Our results show that non-equilibrium evolution allows for solutions in-between extreme cases such as "rare Earth" or extreme colonisation, including scenarios with civilisation fractions between 10^{-2} and 10^{-7}. These would imply still potentially large distances to the next such civilisations, particularly when persistence phenomena are being considered. As previous studies, we confirm that the main uncertainties are due to the lifetime of civilisations as well as the assumed rate of colonisation. For SETI-like studies, we believe that unbiased searches are needed considering both the possibilities that the next civilisations are nearby or potentially very far away., 8 pages, 6 figures, 1 table. Accepted for publication in the International Journal of Astrobiology

Terzaghi's consolidation theory neglects inertial effects on the consolidation of saturated soils. To quantify the inertial effects, in this paper an original one-dimensional small-strain consolidation wave (C-wave) theory is developed, based upon a proposed modified Darcy's law with relaxation time and the equation of motion for soil ensemble. The one-dimensional governing equations were first formulated for self-weight consolidation, followed by a closed-form solution employing the method of separation of variables. The proposed model was then validated against wave velocity measurements and verified against finite-difference analysis. The half-closed self-weight consolidation behaviour was subsequently investigated, compared with Terzaghi's theory, Fillunger–Heinrich's dynamic theory and the u–p form of Biot's wave theory. This research indicates that: (a) superior to conventional models under comparison, the C-wave model enhances the predictability of the C-wave velocity; (b) the dimensionless C-wave coefficient (Cw) dominates the fundamental consolidation behaviour; (c) a wave-diffusion duality underlying the consolidation mechanism contributes qualitatively to the spatial bottom-up pattern and temporal response delay in consolidation observations; and (d) Terzaghi's theory can afford a practically accurate solution provided the Cw and time factor are below and above approximately 0·01, respectively. The C-wave theory may enrich the understanding of consolidation-related phenomena involving an appreciable Cw.

We show that the matter-antimatter asymmetry in the present-day universe is mainly due to the highly suppressed detection probability for the primordial antimatter, which is a direct result of the Dirac-Feynman-Stueckelberg interpretation of antimatter and the extremely time asymmetric expansion of the primordial universe.

The published manuscripts in the area of gyroscope theory were presented mainly by the simplified approaches in which mathematical models contain many uncertainties. New research in machine dynamics opened breakthrough directions in gyroscopic effects of rotating objects that give the correct solutions. The pioneering work meets many problems when solving the scientific innovations that are accompanied by successes and omissions. New mathematical models for the gyroscopic inertial torques were derived with incorrect processing of the integral equations that give distorted results. The gyroscopic devices in engineering manifest gyroscopic effects as the action of the inertial torques which computing is crucial for mathematical describing of their motions. The corrected mathematical processing of the equations for the inertial torques acting in a gyroscope is presented in this manuscript.

In this paper, Galilean orthogonal matrices in G^5 and G_1^5 are obtained with the help of unit quaternions. Moreover, Galilean orthogonal matrices in G^4 and G_1^4 are acquired. These matrices produce Galilelan motions in Galilean spaces. We investigate the invariance of the plane where shear motion is acting in Galilean and pseudo-Galilean spaces. Additionally, related examples of matrices that belong to both spaces are provided. With a similar method, dual Galilean orthogonal matrices are obtained by using unit dual quaternions. Finally, we strengthen our work with examples and draw their figures to explore visual representations.

Let $K$ be a field of characteristic different from 2 and let $G$ be a group. If the algebra $UT_n$ of $n\times n$ upper triangular matrices over $K$ is endowed with a $G$-grading $\Gamma: UT_n=\oplus_{g\in G}A_g$ we give necessary and sufficient conditions on $\Gamma$ that guarantees the existence of a homogeneous antiautomorphism on $A$, i.e., an antiautomorphism $\varphi$ satisfying $\varphi(A_g)=A_{\theta(g)}$ for some permutation $\theta$ of the support of the grading. It turns out that $UT_n$ admits a homogeneous antiautomorphism if and only if the reflection involution of $UT_n$ is homogeneous. Moreover, we prove that if one homogeneous antiautomorphism of $UT_n$ is defined by the map $\theta$ then any other homogeneous antiautomorphism is defined by the same map $\theta$.

By mass-energy equivalence, the gravitational field has a relativistic mass density proportional to its energy density. I seek to better understand this mass of the gravitational field by asking whether it plays three traditional roles of mass: the role in conservation of mass, the inertial role, and the role as source for gravitation. The difficult case of general relativity is compared to the more straightforward cases of Newtonian gravity and electromagnetism by way of gravitoelectromagnetism, an intermediate theory of gravity that resembles electromagnetism., Comment: 39 pages, 1 figure

A gravitational well is a potential well that describes an inhomogeneous gravitational field of an energy gradient, a quantum density gradient of a medium, and a gravitational action potential gradient. A Gravitational well is the distorted or warped Space-time. It is called a well, because it looks some kind of well.In the figure warped space-time is the Gravitational well. The mass of the object influences the depth of the well. It is not a visible thing, But its just the curvature of space-time and its real phenomenon The force of gravity is determined by the gradient of gravitational energy, the deformation vector of quantized space-time and the strength of the gravitational field. It should be noted that the force F of gravity is always directed to the bottom of the gravitational well in the direction of decreasing gravitational energy, quantum density of the medium and gravitational action potential [1-7]. Keywords: Quantum gravity, gravitational well, gradient, gravitational energy, quantum density, gravitational action potential, deformation vector

Organic color-tunable phosphorescent materials depend upon multiple emission centers to achieve color-tunable phosphorescence with changes in excitation wavelength, temperature, time, and other external factors. Organic color-tunable phosphorescent materials are becoming increasingly popular due to their potential applications in anticounterfeiting, encryption and sensing. This brief review focuses on the formation of multiple emission centers in organic color-tunable phosphorescent materials and how to ensure that these multiple emission centers can simultaneously emit. In the future, materials with a large color tunable ranges, increased efficiency, and relatively long lives will be developed.

In this paper, we study the scattering and absorption cross sections of a Schwarzschild–anti-de Sitter black hole surrounded by quintessence. The critical values of the cosmological constant and the normalization factor are obtained. We describe the event horizons and the extremal condition of the black hole surrounded by quintessence. The effects of quintessence on the classical and semi-classical scattering cross sections have been estimated. Additionally, the absorption cross section is studied with the sinc approximation in the eikonal limit. We consider the quintessence state parameter in the particular cases ω = –2/3 and –1/2.

In this letter, we adapt the dilation operator from mathematical morphology to propose dilation distances. These dilation distances are then used for band selection in hyperspectral images. It is shown that dilation distances between bands can capture the spatial distance between the objects. Hence, using dilation-based distances would select those bands which identify spatially separated objects. This is illustrated using both toy and real data sets. Furthermore, we compare the proposed approach with existing methods and show empirically that dilation-distance-based band selection provided competitive results outperforming several methods.

For the open perfect electric conductor (PEC)-dielectric objects, a novel type of volume surface integral equation (VSIE) is proposed to solve the current distribution on both sides of the open PEC surfaces, which cannot be obtained by using the traditional VSIE. In the proposed method, both the electric and magnetic field integral equations are established on both sides of the PEC surfaces, while the basis functions are also defined at the borders of PEC surfaces to consider the current flowing over the edges of PEC surfaces. Compared with the traditional VSIE, due to the asynchronous solution processes of the surface current, the added CPU time for the proposed method is quite limited, while the memory usage is the same. Numerical results verify the validity and efficiency of the proposed method.

Designing and constructing advanced heterojunction architectures are desirable for boosting CO2 photoreduction performance of semiconductor photocatalysts. Herein, we have prepared hierarchical ZnS@ZnIn2S4 core-shell cages with controlled particle sizes using sequential synthesis of Zeolitic imidazolate (ZIF-8) polyhedrons, ZnS cages, and ZnIn2S4 nanosheets on the ZnS polyhedron cages. ZIF-8 polyhedrons are firstly synthesized by a liquid-phase approach. The subsequent sulfidation of the ZIF-8 polyhedrons results in the formation of ZnS polyhedron cages, which act as substrates for fabricating ZnS@ZnIn2S4 core-shell cages by growing ZnIn2S4 nanosheets. The size of ZnS cages can be tuned to optimize CO2 photoreduction performance of hierarchical ZnS@ZnIn2S4 core-shell cages. The synergy of the unique hierarchical core-shell cage-like structure and heterojunction composition endows the hybrid catalyst high incident light utilization, abundant active sites, and effective separation of photoexcited charge carriers. Benefiting from these advantages, the optimized hierarchical ZnS@ZnIn2S4 core-shell cages exhibit enhanced performance for CO2 photoreduction with the CO yield of 87.43 μmol h−1g−1 and 84.3% selectivity, which are much superior to those of single ZnIn2S4 or ZnS. Upon Au decoration, the CO2 photoreduction performance of ZnS@ZnIn2S4 core-shell cages is further enhanced because of the Schottky junctions and surface plasmon resonance effect.

Metal-free purely organic phosphors (POPs) are emerging materials for display technologies, solid-state lighting, and chemical sensors. However, due to limitations in contemporary design strategies, the intrinsic spin-orbit coupling (SOC) efficiency of POPs remains low and their emission lifetime is pinned in the millisecond regime. Here, we present a design concept for POPs where the two main factors that control SOC-the heavy atom effect and orbital angular momentum-are tightly coupled to maximize SOC. This strategy is bolstered by novel natural-transition-orbital-based computational methods to visualize and quantify angular momentum descriptors for molecular design. To demonstrate the effectiveness of this strategy, prototype POPs were created having efficient room-temperature phosphorescence with lifetimes pushed below the millisecond regime, which were enabled by boosted SOC efficiencies beyond 10

We make a first principle study of gravitational pressure in cosmic thermodynamics. The pressure is directly derived from the unified first law, in fact the Einstein field equation in spherically symmetric spacetime. By using this pressure, we obtain the thermodynamics for the FRW universe, especially presenting the gravitational equation of state for the FRW spacetime itself, i.e. $P=P(R_A, T)$ for the first time. Furthermore, we study the Joule-Thomson expansion as an application of the thermodynamic equation of state to find the cooling-heating property of the FRW universe. We demonstrate that there is an inversion temperature for a FRW universe if its enthalpy ${\cal H}$ is negative. These investigations shed insights on the evolution of our universe in view of thermodynamics., Comment: Some new footnotes added, and version published in JHEP

I will begin with the nature of our temporal (t > 0) universe, since without temporal space there would be no gravitation force because gravitational field cannot be created within an empty space. When we are dealing with physical realizability of science, Einstein’s relativity theories cannot be ignored since relativistic mechanics is dealing with very large objects. Nevertheless I will show that huge gravitational waves can be created by a gigantic mass annihilation only within a temporal (t > 0) space. Since gravitational energy has never been consider as a significant component within big bang creation, I will show it is a key component to ignite the big bang explosion, contrary to commonly believed that big bang explosion was ignited by time. I will show a huge gravitation energy reservoir induced by a gigantic mass had had been created over time well before the big bang started. Since the assumed singularity mass within a temporal (t > 0) had had gotten heavier and heavier similar to a gigantic black hole that continuingly swallows up huge chunk of substances within the space. From which we see that it is the gravitational force that triggers the thermo-nuclei big bang creation, instead ignited by time as postulated. Aside the thermo-nuclei creation, it had a gigantic gravitational wave release as mass annihilates rapidly by big bang explosion. From which we see that it is the induced gravitational reservoir changes with time, but not the induced gravity changes (i.e., curves) time–space. In other words if there has no temporal (t > 0) space then there will be no gravitational waves.

This Special Issue concerns inflation, black holes and gravitational waves [...]

In this paper, we propose an angular momentum-based advection technique that can express the turbulent foam effect. The motion of foam particles, which are strongly bound to the motion of the underlying fluid, is viscous, and sometimes clumping problems occur. This problem is a decisive factor that makes it difficult to express realistic foam effects. Since foam particles, which are secondary effects, depend on the motion of the underlying water, in order to exaggerate the foam effects or express more lively foam effects, it is inevitable to tune the motion of the underlying water and then readjust the foam particles. Because of such a cumbersome process, the readjustment of the foam effects requires a change in the motion of the underlying water, and it is not easy to produce such a scene because the water and foam effects must change at the same time. In this paper, we present a method to maintain angular momentum-based force from water particles without tuning the motion of the underlying water. We can restore the lost turbulent flow by additional advection of foam particles based on this force. In addition, our method can be integrated with screen-space projection frameworks, allowing us to fully embrace all the advantages of this approach. In this paper, the turbulence of the foam particles was improved by minimizing the viscous motion of the foam particles without tuning the motion of the underlying water, and as a result, lively foam effects can be expressed.

We study the effects of explicit spacetime-symmetry breaking on primordial tensor fluctuations using an effective-field theory for Lorentz/CPT violation. We find that the graviton is still massless, but that the propagation speed of tensor modes is modified, and we obtain a constraint on the coefficient determining the symmetry breaking on the order of $10^{-15}$ from the recent measurements of the speed of gravity. Due to the symmetry breaking, the de-Sitter phase is modified, and during this inflationary epoch, the power spectrum assumes a slow oscillation around the general-relativity limit; further, we find that the primordial tensor power spectrum retains its scale invariance, but that the amplitude is modified. We also find that the modes which become subhorizon during radiation domination acquire a phase shift proportional to the coefficient for Lorentz violation., Significant revision and changes to results. 9 pages, 5 figures, matches published version

We study supersymmetry conditions for the heterotic pure superstring preserving and N=1 supersymmetry in four dimensions directly from the curved superspace defined by the Berkovits-Howe constraints., Comment: 19 pages, latex

It is believed that relic gravitons are squeezed during inflation. If so, quantum noise induced by them can be significantly enhanced in current interferometers. However, decoherence of the gravitons during cosmic history may change the degree of squeezing. As a first step for analyzing the decoherence of the gravitons, we assume the presence of a sizable magnetic field at the beginning of inflation and study conversion processes of the squeezed gravitons into photons during inflation in the case of minimal coupling between gravitons and photons. We solve the dynamical evolution of a coupled system of gravitons and photons perturbatively and obtain squeezing parameters for the system numerically and analytically. It turns out that the gravitons are robust against the decoherence caused by the cosmological magnetic fields. We also find that the conversion rate of gravitons into photons is at a few percent at most., 29 pages, 7 figures

Lorentz Transformation is the relationship between two different coordinate frames time and space when one inertial reference frame is relative to another inertial reference frame with traveling at relative speed. In this paper, we have derived the transformation formula for the volume charge density in Geometric Product Lorentz Transformation. The changes of volume charge density of moving frame in terms of that rest frame in Geometric Product Lorentz Transformation at various velocities and angles were studied as well.

Problem. The analysis of existing research and publications in which the main problem is highlighted, namely, that many factors are not taken into account when calculating the inertial loads of the car crane arrows. Accounting for these factors will allow you to more accurately determine the inertial loads of the boom of the car crane, to carry out strength-hunches of the elements of the boom and the selection of components of its drive mechanisms. Goal. The purpose of the work is to determine the inertial navan-loads acting on the load and arrow of the automobile-side crane during the unstable movement of its. Methodology. To calculate the inertial loads, the technique of determining the total inertial loads of the car crane boom during joint operations in accordance with the Safety Regulations has been developed. Total inertial loads were determined for the following cases: joint lifting (lowering) of cargo and arrows; lifting the load and turning the boom; lifting and turning the arrow. Results. The resulting dependencies for determining the inertial loads of the rotary boom of the car crane will allow more accurately taking into account multiple factors to calculate the values of these loads in order to conduct strong calculations of the boom, the selection of its components mechanisms. Originality. When calculating inertial loads, the weight and length of the boom are taken into account; weight and height of lifting of cargo; the radius of the arrow crane; rotation speed of the rotary part of the crane; speed of movement of cargo and arrows; start time and braking of cargo lifting mechanisms, change of departure and turn of the boom. The advantage of this technique is its originality. Practical value. The use of this technique allows more accurately taking into account multiple factors to determine the values of the inertial loads of the automobile crane during the unstable movement of the cargo lifting mechanisms, changes in the discharge of the boom and its rotation in order to conduct strong-standing calculations of the boom elements, the selection of its components.

The interplay between the frequency chirping of a broadband laser pulse and the longitudinal chromatic aberration of a focusing optic introduces the superluminal or subluminal behavior to a laser focus. In this paper, we present an analytic expression for an electric field describing a superluminal or subluminal femtosecond laser focus with orbital angular momentum. The analytic expression for a superluminal or subluminal laser focus is obtained through a diffraction integral, in which the focal length is replaced by a time-dependent focal length under the paraxial approximation, and the Fourier transformation. The speed and pulse duration of a laser focus are determined by the total group delay dispersion and a chromaticity parameter defined by the longitudinal chromatic aberration of a dispersive focusing optic. It is shown that it is possible to generate a several femtosecond superluminal orbital angular momentum laser focus in the focal region.

This paper shows that gravitational results of general relativity (GR) can be reached by using special relativity (SR) via a SR Lagrangian that derives from the corresponding GR time dilation and vice versa. It also presents a new SR gravitational central scalar generalized potential V=V(r,r.,ϕ.), where r is the distance from the center of gravity and r.,ϕ. are the radial and angular velocity, respectively. This is associated with the Schwarzschild GR time dilation from where a SR scalar generalized potential is obtained, which is exactly equivalent to the Schwarzschild metric. Thus, the Precession of Mercury’s Perihelion, the Gravitational Deflection of Light, the Shapiro time delay, the Gravitational Red Shift, etc., are explained with the use of SR only. The techniques used in this paper can be applied to any GR spacetime metric, Teleparallel Gravity, etc., in order to obtain the corresponding SR gravitational scalar generalized potential and vice versa. Thus, the case study of Newtonian Gravitational Potential according to SR leads to the corresponding non-Riemannian metric of GR. Finally, it is shown that the mainstream consideration of the Gravitational Red Shift contains two approximations, which are valid in weak gravitational fields only.

In this paper, I give a counterexample to a claim made in Norton (2008) that empirically equivalent theories can often be regarded as theoretically equivalent by treating one as having surplus structure, thereby overcoming the problem of underdetermination of theory choice. The case I present is that of Lorentz's ether theory and Einstein's theory of special relativity. I argue that Norton's suggestion that surplus structure is present in Lorentz's theory in the form of the ether state of rest is based on a misunderstanding of the role that the ether plays in Lorentz's theory, and that in general, consideration of the conceptual framework in which a theory is embedded is vital to understanding the relationship between different theories.

Loop diagrams with near-Planck energies create a strong external gravitational field, which slows down local processes for distant observers up to their freezing. Since Planck length is the gravitational radius of the system of quanta, the events of this and smaller scale cannot occur in finite world time t and do not contribute to the S-matrix. Consequently, gravitational time dilation, leading to a strong redshift of local frequencies, provides gravitational self-regularization of the loop diagrams. The loop corrections without gravity effects, cut off at Planck energy, give upper bounds for the corrections with gravity effects and this fact leads to simple rules of gravitational regularization. The corrections with quanta of gauge fields and gravitons are small, and the perturbation theory series converge. At pre-Planck energies, one-loop graviton contributions are sufficient, since the multi-loop ones are damped by high degrees of the relation “energy/Planck energy”. Scalar field with power-law growing corrections should be effective field. Non-linearity of fields enhances gravity and get faster freezing, which suppresses the high energy terms. Nonrenormalizable models are finite, but become consistent only when their loop corrections remain small on Planck scale and this occurs in quantum gravity. Gravitationally regularized Extended Standard Model (ESM), including gravitons and Standard Model with effective scalars, is renormalizable and finite, which simplifies its further generalization.

Intense light traps and binds small particles, offering unique control to the microscopic world. With incoming illumination and radiative losses, optical forces are inherently nonconservative, thus non-Hermitian. Contrary to conventional systems, the operator governing time evolution is real and asymmetric (i.e., non-Hermitian), which inevitably yield complex eigenvalues when driven beyond the exceptional points, where light pumps in energy that eventually “melts” the light-bound structures. Surprisingly, unstable complex eigenvalues are prevalent for clusters with ~10 or more particles, and in the many-particle limit, their presence is inevitable. As such, optical forces alone fail to bind a large cluster. Our conclusion does not contradict with the observation of large optically-bound cluster in a fluid, where the ambient damping can take away the excess energy and restore the stability. The non-Hermitian theory overturns the understanding of optical trapping and binding, and unveils the critical role played by non-Hermiticity and exceptional points, paving the way for large-scale manipulation., Non-conservativeness plays a mysterious role in optical trapping. Applying the non-Hermitian theory, the authors showed that the existence of exceptional points drives the Lorentz force to lose its ability to bind clusters of ~10 or more microparticles, unless remedied by dissipative forces.

The continuous iteration of an exponential-type function allows to describe a whole range of growths between logarithmical and exponential. This principle has been applied to a class of lifetime di...

The working principle of a cycloidal propeller is complicated given that its blades are engaged in multi- degrees of freedom (DOF) motions. The instantaneous forces developed on the blades were stu...

Recently, two kinds of deformed schwarzschild spacetime have been proposed, which are the black-bounces metric (\cite{2019JCAP...02..042S,2021PhRvD.103h4052L}) and quantum deformed black hole (BH) (\cite{2021arXiv210202471B}). In present work, we investigate the rotating spacetime of these deformed Schwarzschild metric. They are exact solutions to the Einstein$'$s field equation. We analyzed the properties of these rotating spacetimes, such as event horizon (EH), stationary limit surface (SIS), structure of singularity ring, energy condition (EC), etc., and found that these rotating spacetime have some novel properties., 7 pages, 0 figures, Accepted for publication in European Physical Journal C

In this paper, we studied the evolutions of the innermost stable circular orbits (ISCOs) in dynamical spacetimes. At first, we reviewed the method to obtain the ISCO in Schwarzschild spacetime by varying its conserved orbital angular momentum. Then, we demonstrated this method is equivalent to the effective potential method in general static and stationary spacetimes. Unlike the effective potential method, which depends on the presence of the conserved orbital energy, this method requires the existence of conserved orbital angular momentum in spacetime. So it can be easily generalized to the dynamical spacetimes where there exists conserved orbital angular momentum. From this generalization, we studied the evolutions of the ISCOs in Vaidya spacetime, Vaidya-AdS spacetime and the slow rotation limit of Kerr–Vaidya spacetime. The results given by these examples are all reasonable and can be compared with the evolutions of the photon spheres in dynamical spacetimes.

In this paper, we have studied the gravitational baryogenesis of isotropic and homogeneous universe in the frame-work of general relativity. We investigate an exact and new solution of Einstein's field equations for FRW metric. Our solution represents a transitioning model of the universe which was expanding in decelerated mode and it transit in accelerated mode after dominance of cosmological constant $\Lambda$. We observe that gravitational baryogenesis occurs in the derived universe and derived baryon entropy ratio is in good agreement with its observational value., Comment: 8 Pages, 4 Figures, Accepted in Gravitation and Cosmology

This paper assesses the thermodynamic properties of classical Schwarzschild Black Holes. We review the thermodynamic cycle in the Geroch gedanken experiment in its relation to the classical limit of Hawking temperature, and conclude that a minimal distance requirement for pouring out radiation onto the event horizon in the gedanken experiment implies the assignment of temperature $${{T}_{{{\text{BH}}}}} \to 0$$ asympotically rather than exact absolute zero $$K$$ : a classical Schwarzschild horizon is an asymptotically zero Kelvin mechanical thermostat operated at asymptotically unit efficiency. We classify the gravitational heat pumping work done by horizon surface gravitation as perpetual motion of the third kind. The latter property does not, however, violate the Second Law, because it is impossible to extract gravitational energy from a classical Schwarzschild Black Hole in quasi-static equilibrium. The classical limit of the Bekenstein–Hawking (quantum) entropy formula is divergent as $${{S}_{{{\text{BH}}}}} \to \infty $$ , yet since $$\delta {{S}_{{{\text{BH}}}}} \to 0$$ the Nernst statement of the Third Law is not violated. Aided by the Bekenstein bound, it is shown that the Generalized Second Law persists to hold in its classical limit, when applied to the joint system of Schwarzschild Black Hole and infalling radiation gas in the Geroch gedanken experiment. The minimal horizon distance $$\delta r$$ is inferred from the Bekenstein bound, and ensures that the Geroch thermodynamic cycle be processed reversibly. The overall conclusion is that the laws of thermodynamics are not transcended by classical Schwarzschild Black Holes, despite their extremal thermodynamic properties.

In this paper, we study the thick brane system in the so-called f(Q) gravity, where the gravitational interaction was encoded by the nonmetricity Q like scalar curvature R in general relativity. With a special choice of $$f(Q)=Q-b Q^n$$ f ( Q ) = Q - b Q n , we find that the thick brane system can be solved analytically with the first-order formalism, where the complicated second-order differential equation is transformed to several first-order differential equations. Moreover, the stability of the thick brane system under tensor perturbation is also investigated. It is shown that the tachyonic states are absent and the graviton zero mode can be localized on the brane. Thus, the four-dimensional Newtonian potential can be recovered at low energy. Besides, the corrections of the massive graviton Kaluza–Klein modes to the Newtonian potential are also analyzed briefly.

In this paper, optimal control models subject to two types of discrete-time stochastic noncausal systems are considered in order. The stochastic noncausal systems are stochastic singular systems assumed to be regular alone. Based on the principle of dynamic programming, a recurrence equation is deduced to simplify the optimal control models. Then, by applying the recurrence equation, a bang-bang optimal control problem ruled by a linear stochastic noncausal system and an optimal control problem for a stochastic noncausal system with quadratic inputs are both solved, and the optimal solutions are presented through analytical expressions. A numerical example is provided to illustrate the effectiveness of the results about the bang-bang optimal control problem.

This work presents a new approach to gravitation. Instead of seeing mass as a source of gravitation, the opposite is assumed here. Namely, gravitation has been there first and ever since. Masses were brought into the game later, following highly energetic interactions between electromagnetic fields (photons), with the gravitation field. These interactions resulted in photon annihilation and pair (or jets) production processes. Though pair production is forbidden kinematically in an empty space, itis allowed when the interaction of an incoming photon with gravitation field occurs. Quantum fluctuations in the gravitation field create very intense geometrical distortions in spacetime which in turn allows for photons to undergo momentum changes in favor of pair production processes.

A comprehensive numerical analysis has been implemented to delineate the transport characteristics for flow of Newtonian fluid inside a channel with a porous slab and internal wavy walls. The heat ...

This paper introduces a scientific approach for the simulation and analysis of electromagnetic radiation (EMR) patterns indoors. It applies physics laws in analyzing EMR interaction within real-lik...

This paper shows that the stochastic approach to solving the problem of the scattering of elementary particles on crystal can serve as an alternative to Louis de Broglie's hypothesis on the wave properties of material particles. The results of calculations presented in this work are in good agreement with the experimentally obtained electron diffraction patterns and X-ray diffraction patterns and the Davisson-Germer experiments.

Inertial sensors are devices that can monitor inertial movements, such as linear acceleration and angular motions, in industrial and human systems. For portable and wearable applications, inertial sensors must be self-powered and miniaturized. In this article, we report a self-powered inertial sensor with high accuracy based on carbon nanotube (CNT) yarn. By harvesting the mechanical energy of a coiled CNT yarn, our inertial sensor can detect inertial movements without the need for external power. For practical applications, the sensor can monitor various inertial movements, such as vibrations, external impacts, tilting, and body motions (squatting, walking, running, and jumping motions). These findings suggest that the self-powered inertial sensor exhibits the advantages of portability and wearability in industrial and human system applications.

A broader concept of “resistance to acceleration” than used in classical dynamics, called “inertial resistance”, is quantified for both inertial and non-inertial relativistic motion. Special Relativity shows that inertial resistance is more than particle inertia and originates from Minkowski spacetime structure. Current mainstream explanations of inertia do not take inertial resistance into account and are, therefore, incomplete.

The differential (resp. boomerang) spectrum is an important parameter to estimate the resistance of cryptographic functions against some variants of differential (resp. boomerang) cryptanalysis. This paper aims to determine the differential and boomerang spectrums of some power permutations. In 1997, Helleseth and Sandberg proved that the differential uniformity of $x^{\frac {p^{n}-1}{2}+2}$ over $\mathbb {F}_{p^{n}}$ , where p is an odd prime, is less than or equal to 4. In this paper, we first determine the differential spectrum of $x^{\frac {3^{n}-1}{2}+2}$ over $\mathbb {F}_{3^{n}}$ with n odd and then compute its boomerang spectrum based on the differential spectrum. In addition, in 2018, Boura and Canteaut determined the boomerang spectrum of the inverse function over $\mathbb {F}_{2^{n}}$ with n even. Following their work, we characterize the boomerang spectrum of the inverse function $x^{p^{n}-2}$ over $\mathbb {F}_{p^{n}}$ for any odd prime p.