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The oscillation of neutrino flavors, due to its interferometry nature, is extremely sensitive to the phase differences developing during the propagation of neutrinos. In this paper we investigate the effect of the Violation of Equivalence Principle (VEP) on the flavor oscillation probabilities of atmospheric and cosmic neutrinos observed at neutrino telescopes such as IceCube. Assuming a general parameterization of VEP, dubbed extended parameter space, we show that the synergy between the collected data of high energy atmospheric and cosmic neutrinos severely constrains the VEP parameters. Also, the projected sensitivity of IceCube-Gen2 to VEP parameters is discussed., Comment: 19 pages, 8 figures; v2: minor clarifications added, matches the version published in JCAP

The single-source equivalence principle algorithm has been proposed as an efficient solution for analyzing large array structures. However, due to the discretization error of the identity operator, the accuracy of single-source equivalence principle algorithm is not good. In this paper, a single-source tangential equivalence principle algorithm is proposed to improve the accuracy by using the tangential field projection scheme. Based on this scheme and extinction theorem, a new relation between equivalence electric current and magnetic current can be established which has more accurate discretization. Moreover, it is demonstrated that the single-source equivalence principle algorithm can be derived from one type of single-source tangential equivalence principle algorithm. Numerical examples are designed to demonstrate the accuracy improvement of the proposed method.

The premise and foundation of targets' analysis and recognition is to quickly and accurately obtain the radar cross section (RCS) of micro-motion group targets in the middle of trajectory. By analyzing the process of obtaining dynamic RCS by fitting full static RCS, this paper points out that the traditional method cannot realize the simulation of RCS of micro-motion group targets, and establishes all types of micromotion models of pyramidal targets. Combined with the domain decomposition method based on equivalence principle algorithm for the body of revolution (EPA-BOR), the fast simulation of dynamic RCS of micro-motion group targets in the middle part of trajectory is implemented and verified.

The challenges of predicting wireless device performance may be addressed by constructing hybrid solutions with rigorous models around sensitive regions and approximate methods over electrically-large smooth structures. The surface equivalence principle supports constructing multiple scattering problems with per-domain scattering algorithms, but discretization over electrically large surfaces is prohibitively expensive. A Schur complement applied to the equations expresses a generalized hybrid method with clear physical interpretation. An example case with results is presented.

A recent proposal by Shuler regarding a postulate-based derivation of a family of metrics describing the gravitational field outside a static spherically symmetric mass distribution is reviewed. All of Shuler’s gravities agree with the Schwarzschild solution in the weak-field limit, but they differ in the strong-field domain, i.e., close enough to a sufficiently compact source of the field. It is found that the evoked postulates of i) momentum conservation and ii) consistency of field strength measurement are satisfied in all metric theories of gravity compatible with the Einstein equivalence principle, no matter what the form of the metric. Therefore, they cannot be used, within any correct deduction, to derive a particular metric. Shuler’s derivations are based on an inconsistent set of correspondences between local and distant measurements. Furthermore, it is shown here that out of the family of possible metrics given by Shuler only one member, the Schwarzschild metric, satisfies a standard relativistic generalization of Newton’s law of gravitation, suggesting the others to be unphysical.

The Zhaoshan long-baseline Atom Interferometer Gravitation Antenna (ZAIGA) is a new type of underground laser-linked interferometer facility, and is currently under construction. It is in the 200-meter-on-average underground of a mountain named Zhaoshan which is about 80 km southeast to Wuhan. ZAIGA will be equipped with long-baseline atom interferometers, high-precision atom clocks, and large-scale gyros. ZAIGA facility will take an equilateral triangle configuration with two 1-km-apart atom interferometers in each arm, a 300-meter vertical tunnel with atom fountain and atom clocks mounted, and a tracking-and-ranging 1-km-arm-length prototype with lattice optical clocks linked by locked lasers. The ZAIGA facility will be used for experimental research on gravitation and related problems including gravitational wave detection, high-precision test of the equivalence principle of micro-particles, clock based gravitational red-shift measurement, rotation measurement and gravito-magnetic effect., 20 pages, 15 figures

A modified equivalence principle algorithm with bod of revolution (EPA-BoR) is proposed to compute the electromagnetic (EM) scattering from a swarm of unmanned aerial vehicles (UAVs). The method can use the repetition of UAVs in the swarm for whatever postures of UAVs are. Numerical results demonstrate the efficiency and accuracy of the presented scheme.

Reduction of flow compressibility with the corresponding ideally invariant helicities, universally for various fluid models of neutral and ionized gases, can be argued statistically and associated with the geometrical scenario in the Taylor-Proudman theorem and its analogues. A `chiral base flow/field', rooted in the generic intrinsic local structure, as well as an `equivalence principle' is explained and used to bridge the single-structure mechanics and the helical statistics. The electric field fluctuations may similarly be depressed by the (self-)helicities of the two-fluid plasma model, with the geometry lying in the relation between the electric and density fields in a Maxwell equation., Comment: 1 figure

A space with deformed Poisson brackets for coordinates and momenta leading to the minimal length is considered. Features of description of motion of a body in the space are examined. We propose conditions on the parameters of deformation on which Poisson brackets for coordinates and momenta of the center-of-mass reproduce relations of deformed algebra, kinetic energy of a body is independent of its composition, and the weak equivalence principle is preserved in the deformed space. Influence of minimal length on the motion of the Sun-Earth-Moon system is studied. We find that deformation of the Poisson brackets leads to corrections to the accelerations of the Earth and the Moon toward the Sun, as a result the Eotvos-parameter does not vanish even if we consider equality of gravitational and inertial masses. The upper bound for the minimal length is estimated using results of the Lunar laser ranging experiment., Comment: to appear in International Journal of Modern Physics D

When designing or improving a chemical process, it is often difficult to know when a proposed design is “good enough”. This is due in part to a lack of knowledge of what is possible. With some benchmark against which to compare, design engineers would be better equipped to determine when a design is sufficiently favorable. This work presents recent updates to the CFSTR Equivalence Principle, developed by Feinberg and Ellison, which for steady-state processes allows us to determine the highest attainable production rate of a desired component in a given chemistry for a specified feed. We show that the problem can be reformulated to obtain target bounds on reaction selectivity and that realistic capacity constraints can be incorporated to obtain useful results. We also demonstrate that the CFSTR Equivalence Principle is applicable to all process, not just those that operate at steady state. Finally, we show that we can incorporate minimum work requirements to obtain screening-level economic metrics. These methodologies are demonstrated on a number of different chemistries.

A generalized version of the hypersonic equivalence principle for viscous flows is implemented by using the direct simulation Monte Carlo (DSMC) method. The 3-dimensional steady hypersonic flow over a slender body could be reduced to a simplified 2-dimensional unsteady flow, as long as the high-speed velocity component perpendicular to the 2-dimensional plane is retained. As a result, the strongly sheared and high temperature boundary layer flow is induced, and the friction drag and aeroheating problem can be discussed. The DSMC method which is naturally unsteady, 3-dimensional and robust to the surface motion is very appropriate to implement this principle. Foundamental 1-dimensional Rayleigh flow, 2-dimensional Blasius flow and practical 3-dimensional complex interaction flow are studied based on the generalized hypersonic equivalence principle. This study indicates the feasibility of the dimensionality reduction in DSMC simulation of the complex hypersonic flows, as well as the potential application value of the generalized hypersonic equivalence principle for the friction force and aeroheating prediction.

We investigate the particle-antiparticle symmetry of the gravitationally coupled Dirac equation, both on the basis of the gravitational central-field problem and in general curved space-time backgrounds. First, we investigate the central-field problem with the help of a Foldy-Wouthuysen transformation. This disentangles the particle from the antiparticle solutions, and leads to a "matching relation" of the inertial and the gravitational mass, which is valid for both particles as well as antiparticles. Second, we supplement this derivation by a general investigation of the behavior of the gravitationally coupled Dirac equation under the discrete symmetry of charge conjugation, which is tantamount to a particle -> antiparticle transformation. Limitations of the Einstein equivalence principle due to quantum fluctuations are discussed. In quantum mechanics, the question of where and when in the Universe an experiment is being performed, can only be answered up to the limitations implied by Heisenberg's Uncertainty Principle, questioning an assumption made in the original formulation of the Einstein equivalence principle. Furthermore, at some level of accuracy, it becomes impossible to separate non-gravitational from gravitational experiments, leading to further limitations., 19 pages; LaTeX article style

This paper describes automotive windscreen antenna analysis in Feko, requiring the hybridization of the multilevel fast multiple method based on the surface equivalence principle, the finite element method and windscreen antenna analysis for the most efficient solution.

The application of the mass-energy-information equivalence principle developed after the experimentally demonstrated Landauer's principle on thermodynamics, entropy, and information is an unexplored but promising path in search of objectivity and compatibility between strict physical and mathematical entities and relative human behavior in biodiversity conservation issues. Conservation culturomics is proposed as the epistemic methodology and programme to trace the evolution in cultural human-nature relationships. Historically, controversies do persist between pro- vs. non- environmental opinions and policies. The proposed combination of physics and culturomics is feasible, although complex, multileveled, and depending on a series of academic, technical, and political prerequisites. In the era of staggering information technologies, Internet use proliferation and cultural relativism, reliable information on conservation knowledge vs. often unfounded story-tellings is a sine qua non for the development of badly needed modern global conservation strategies, targets, and goals., Mass; energy; information; public interest; Conservation Culturomics

In this paper, we aim to determine an optimal insurance premium rate for health-care in deterministic and stochastic SEIR models. The studied models consider two standard SEIR centres characterised by migration fluxes and vaccination of population. The premium is calculated using the basic equivalence principle. Even in this simple set-up, there are non-intuitive results that illustrate how the premium depends on migration rates, the severity of a disease and the initial distribution of healthy and infected individuals through the centres. We investigate how the vaccination program affects the insurance costs by comparing the savings in benefits with the expenses for vaccination. We compare the results of deterministic and stochastic models.

A mathematical model employing the concept of the energy-equivalent inhomogeneity combined with the method of conditional moments has been applied to analyze short-fiber composites. The fibers are parallel, randomly distributed, and their interphase is assumed to be adequately described by the Gurtin-Murdoch material surface model. The properties of the energy-equivalent fiber, incorporating properties of the original fiber and its interphase, are determined on the basis of Hill's energy equivalence principle assuming its cylindrical shape. To describe random distribution of fibers a statistical method, the method of conditional moments, has been employed. Closed-form formulas for the components of the effective stiffness tensor of short-fiber reinforced composites have been developed which, in the limit, compare well with the results available in the literature for infinite parallel fibers with Gurtin-Murdoch interphase model. Influence of fiber length on contribution of the surface effects to the effective properties of the material containing cylindrical cavities has been analyzed for all five independent components of its stiffness tensor, and for two sets of surface properties in the Gurtin-Murdoch model.

A new domain decomposition scheme based on equivalence principle algorithm (EPA) is proposed for analyzing electromagnetic scattering from connected structures. The EPA transforms the unknown of inside scatterers to the unknown on the equivalence surfaces which enclose the scatterers. The challenge arises when the equivalence surface intercepts the connected scatterers, because the current will be singular at the connection that is hard to model. In this paper, a new scheme based on source reconstruction method (SRM) is introduced to deal with the connected problems. This scheme can avoid the current singularity and keep the good convergence of EPA equations. Furthermore, generalized EPA (GEPA) is proposed to improve the theory of EPA and the ability to solve real life problems. Numerical results demonstrate the accuracy and efficiency of the proposed method.

The Weak Equivalence Principle (WEP) is at the basis of General Relativity – the best theory for gravitation today. It has been and still is tested with different methods and accuracies. In this paper an overview of tests of the Weak Equivalence Principle done in the past, developed in the present and planned for the future is given. The best result up to now is derived from the data of torsion balance experiments by Schlamminger et al. (2008). An intuitive test of the WEP consists of the comparison of the accelerations of two free falling test masses of different composition. This has been carried through by Kuroda & Mio (1989, 1990) with the up to date most precise result for this setup. There is still more potential in this method, especially with a longer free fall time and sensors with a higher resolution. Providing a free fall time of 4.74 s (9.3 s using the catapult) the drop tower of the Center of Applied Space Technology and Microgravity (ZARM) at the University of Bremen is a perfect facility for further improvements. In 2001 a free fall experiment with high sensitive SQUID (Superconductive QUantum Interference Device) sensors tested the WEP with an accuracy of 10 - 7 (Nietzsche, 2001). For optimal conditions one could reach an accuracy of 10 - 13 with this setup (Vodel et al., 2001). A description of this experiment and its results is given in the next part of this paper. For the free fall of macroscopic test masses it is important to start with precisely defined starting conditions concerning the positions and velocities of the test masses. An Electrostatic Positioning System (EPS) has been developed to this purpose. It is described in the last part of this paper.

We propose a multiscale solver of equivalence principle algorithm with a body of revolution (BoR) equivalence surface (ES). First, the whole object is decomposed into subdomains; the ESs are defined as proper BoRs (e.g., spheres in this work) to enclose each subdomain. The Rao–Wilton–Glisson (RWG) and BoR basis functions are defined on each sphere, respectively. Second, the octree is constructed in each nonzero subdomain; the multilevel fast multipole algorithm (MLFMA) is employed to solve the equivalent currents on the ES individually, and then the equivalent currents are projected from RWG onto the BoR basis functions. The couplings between neighboring subdomains are evaluated directly using MLFMA, and the separated subdomains are substituted by the ES-to-ES couplings, and are evaluated efficiently by the BoR method of moments (BoR–MoM). To solve the equation system, a hybrid inner and outer iterative solver is employed, where the inner iteration is used to solve each local subdomains and the outer iteration is used to update the global solutions by collecting all the local solutions. Numerical results and discussions demonstrate the validity of the proposed work.

Comparing the parameterized post-Newtonian parameter $\gamma$ values for different types of particles, or the same type of particles with different energies is an important method to test the Einstein Equivalence Principle (EEP). Assuming that the observed time delays are dominated by the gravitational potential of the Laniakea supercluster of galaxies, better results of EEP constraints can be obtained. In this paper, we apply photons from three kinds of cosmic transients, including TeV blazars, gamma-ray bursts as well as fast radio bursts to constrain EEP. With a gravitational field far more stronger than a single galaxy, we obtain 4--5 orders of magnitude more stringent than the pervious results., Comment: Accepted by Journal of High Energy Astrophysics. 12 pages

Spherical actuator is a device that can achieve multiple degree-of-freedom (DOF) rotary motions in a single joint. It has a bright application prospect on moment gyros and satellite systems. Cylindrical shaped PM pole is widely used because of easy fabrication and pattern of magnetization. However, its topology and structure cause difficulties in accuracy magnetic modeling. Thus, the structure optimization and performance design become complicated. This paper proposes a novel magnetic field method for spherical actuator with cylindrical shaped PM poles based on geometrical equivalence principle. For convenient expression of magnetic field, three types of approximated dihedral cone shaped magnet poles are put forward based on different equivalent principles. On the basis of optimal equivalent principle, accurate harmonic model is set up with the magnetic field formulated. In addition, the analytical result is confirmed by numerical simulation from different dimensions. A research prototype with 8-PM-poles outer rotor and 24-coils stator is assembled and an experimental setup is established. The experimental results show experimental curves, analytical curves and FEM curves match with each other well which proves the accuracy of the proposed model. Thus, the indirect method of modeling magnetic field for spherical actuator with cylindrical shaped PM poles can be an effective tool. The magnetic field results can be the foundation for further study.

This essay examines Friedman’s recent approach to the analysis of physical theories. Friedman argues against Quine that the identification of certain principles as 'constitutive' is essential to a satisfactory methodological analysis of physics. I explicate Friedman’s characterization of a constitutive principle, and I evaluate his account of the constitutive principles that Newtonian and Einsteinian gravitation presuppose for their formulation. I argue that something close to Friedman’s thesis is defensible.

Lorentz symmetry violation (LV) was recently proposed to be testable with a new method, in which the effect of the violation is described as a certain local interaction Shaniv et al (2018 Phys. Rev. Lett. 120 103202). We revisit this LV effect in the paper and show that it is not only local, but it also represents a classical violation according to the recent quantum formulation of the Einstein equivalence principle (EEP). Based on a harmonically trapped spin-1/2 atomic system, we apply the results of table-top experiments testing LV effect to estimate the corresponding violation parameter in the quantum formulation of EEP. We find that the violation parameter is indeed very small, as expected by the earlier theoretical estimation.

This study presents a theoretical approach to characterize the mesoscopic dynamic fracture behaviors of concrete. Firstly, different fracture behaviors are determined from energy criteria. Secondly, by considering the energy equivalence principle, the Saint-Venant’s principle and the Newton’s laws of motion, an extended self-consistent finite stress model (XSFSM) is established for dynamic fracture analysis of concrete-like cementitious materials. The XSFSM is validated and modified by comparing with the existing models in design codes and the curve fitting models in literatures. Thirdly, the XSFSM is utilized to propose the meso-level fracture criterion of concrete based on a morphological material model. Parametric study illustrates that the criterion can predict the transgranular and intergranular failure modes of concrete under quasi-static to dynamic loading. At last, assumptions and limitations of the present theoretical approach and its prospects in computational methods are discussed.

In this paper, some analogies between the Shapiro effect in the solar gravitational field and the Sagnac phase shift have been found. Starting from Einstein equivalence principle (EEP), which states the equivalence between the gravitational force and the pseudo-force experienced by an observer in a noninertial frame of reference, we imagine an observer on a rotating platform immersed in a gravitational field. In the Shapiro effect, for example, we know that the speed of an electromagnetic signal, calculated from the Earth, is less than [Formula: see text], but, if we calculate the speed using a clock at rest in the solar gravitational field, where the photon is passing, we get that the speed of light is [Formula: see text]. Similarly, by considering the fictitious gravitational field of the rotating platform, if we look for a clock with respect to which the signal speed is [Formula: see text], we can interpret the time delay as a gravitational effect.

The optical equivalence principle is analyzed according to the possibility of describing unbounded states, and the suitable approximations are calculated for highly energetic phenomena. Among these possibilities, the relevance for laser fields, interferometers, and optomehcanical systems are implemented. Their suitableness for research in General Relativity, Cosmology, and High-Energy Physics are outlined.

The effective field theory of dark energy is generalized to incorporate dark matter, which is modelled using a complex scalar field with a global $U(1)$ symmetry. The dark matter model used here has similarities to models of ultralight axion. Generic interaction terms in the dark matter sector violate the weak equivalence principle. The degree to which such violations can occur is constrained using a number of recent analyses and forecasts in cosmology., 47 pages, 8 figures

In this paper, the generalized single-source tangential equivalence principle algorithm (GSST-EPA) is combined with contact-region modeling (CRM) to solve the electromagnetic scattering of array structures. The CRM is used to decompose the array structures into subdomains with the same size. Then each subdomain is enclosed by the same equivalence surface. The GSST-EPA can be used to transfer the unknowns of subdomains onto the equivalence surfaces, which can reduce the number of unknowns and improve the conditioning of final matrix. The numerical results are given to demonstrate the accuracy and efficiency of the proposed method.

Quasi-periodic electromagnetic surfaces have similar planar elements located on periodic lattices. Because the elements are different, the periodic boundary condition is not accurate for full wave modeling of quasi-periodic electromagnetic surfaces. In order to utilize the periodicity of elements to accelerate the full wave simulation, this work applies the idea of equivalence principle algorithm and projects the current of different elements onto periodic equivalence surfaces. The projection process can be written in matrix operators. For unknowns on the equivalence surfaces, the reduced basis method can be applied to reduced the number of unknowns. After extracting the periodicity or the translational invariance of the element alignment, the fast Fourier transform can be used to accelerate matrix vector production in iterative solvers for method of moments. It can reduce the computational complexity of matrix vector production from $O(N^{2})$ to $O(N\log\, N)$, where $N$ is the number of elements. Numerical examples show the algorithm can accelerate iterative solvers and has potential to solve large quasi-periodic electromagnetic surfaces.

This paper describes recent advances of the commercial CEM code FEKO, as well as the wave propagation and radio network planning tool WinProp. This includes the simulation of characterized surfaces (complex radomes, frequency-selective surfaces) with RL-GO, a direct solver for ACA (adaptive cross approximation), and supporting FEM (finite element method) and MoM (method of moments) with SEP (surface equivalence principle) in the same model.

In this Essay, we give a correct interpretation of a historical experiment by Kundig on the transverse Doppler shift in a rotating system (Mossbauer rotor experiment). This experiment has been recently first reanalyzed, and then replied by an experimental research group. The results of reanalyzing the experiment have shown that a correct re-processing of Kundig's experimental data gives an interesting deviation of a relative redshift between emission and absorption resonant lines from the standard prediction based on the relativistic dilatation of time. Subsequent new experimental results by the reply of Kundig experiment have shown a deviation from the standard prediction even higher. By using the Equivalence Principle (EP), which states the equivalence between the gravitational "force" and the pseudo-force experienced by an observer in a non-inertial frame of reference (included a rotating frame of reference), here the theoretical framework of the Mossbauer rotor experiment is reanalyzed directly in the rotating frame of reference through a general relativistic treatment. It will be shown that previous analyses missed an important effect of clock synchronization. By adding this new effect, the correct general relativistic prevision is in perfect agreement with the new experimental results. Such an effect of clock synchronization has been missed in various papers in the literature, with some subsequent claim of invalidity of the relativity theory and/or some attempts to explain the experimental results through "exotic" effects. The general relativistic interpretation in this Essay shows, instead, that the new experimental results of the Mossbauer rotor experiment are a new, strong and independent, proof of general relativity., 7 pages, 1 figure. This Essay received an Honorable Mention in the 2018 Essay Competition of the Gravity Research Foundation. Dedicated to the memory of Enrico Lista. Founded on the research paper arXiv:1502.04911. arXiv admin note: substantial text overlap with arXiv:1602.04212

In this paper, a combined 1D and 2D Discontinuous Galerkin Time-Domain (DGTD) method is proposed to model multilayer power-ground (PG) planes with narrow slots. The 2D Maxwell's equations for the PG plane pairs are coupled with the Telegrapher's equations for the slots based on the surface equivalence principle. They are solved by 2D DGTD method and 1D DGTD method, respectively. The accuracy of the proposed method is validated against full-wave time-domain commercial software.

An improved generalized single-source tangential equivalence principle algorithm (GSST-EPA) is proposed for analyzing array structures with connected elements. In order to use the advantages of GSST-EPA, the connected array elements are decomposed and computed by a contact-region modeling (CRM) method, which makes that each element has the same meshes. The unknowns of elements can be transferred onto the equivalence surfaces by GSST-EPA. The scattering matrix in GSST-EPA needs to be solved and stored only once due to the same meshes for each element. The shift invariant of translation matrices is also used to reduce the computation of near-field interaction. Furthermore, the multilevel fast multipole algorithm (MLFMA) is used to accelerate the matrix-vector multiplication in the GSST-EPA. Numerical results are shown to demonstrate the accuracy and efficiency of the proposed method.

In Chapter 6, we discussed the Release/Reuse Equivalence principle. It’s the first principle of package cohesion: it tells an important part of the story about which classes belong together in a package, namely those that you can properly release and maintain as a package. You need to take care of delivering a package that is a true product.

The paper deals with the electromagnetic dosimetry model for the lossy homogeneous biological body. The model is based on the use of electric field integral equation (EFIE) in the frequency domain derived using the surface equivalence theorem and the boundary conditions for the electric field. The scattered electric field is expressed in terms of the equivalent electric and magnetic current densities which are expanded using Rao–Wilton–Glisson (RWG) basis function, and a point wise orthogonal nˆ×RWG basis function, respectively. Some illustrative results for the obtained equivalent surface current densities are given. The electromagnetic model can be useful in high frequency dosimetry of the human brain and also in modeling of medical technique such as transcranial magnetic stimulation (TMS).

The first of the actual package design principles discussed in this book is the Release/Reuse Equivalence principle. This principle says

In this chapter, we study the axisymmetric indentation problem for a transversely isotropic elastic half-space with finite friction. By treating the indentation problem incrementally, its general solution is reduced to that of the problem for a flat-ended cylindrical indenter with an unknown stick-slip radius. The solution to the latter problem in the transversely isotropic case is obtained via Turner’s equivalence principle Turner (Int J Solids Struct 16:409–419, 1980 [15]), from the analytical solution given by Spence (J Elast 5:297–319, 1975 [12]) in the case of isotropy. The generalization, due to Storakers and Elaguine (J Mech Phys Solids 53:1422–1447, 2005 [14]), of the BASh relation for incremental indentation stiffness, and also accounting for the friction effects, is presented. The case of self-similar contact with friction is considered in more detail.

In this paper, an efficient numerical method for calculating the near-field from planar power distribution network (PDN) with decoupling capacitors is proposed. This method is based on field equivalence principle method combined with the plane-pair partial element equivalent circuit (PP-PEEC). The proposed combined approach is validated with results from the 3-D full-wave simulation.

In this communication we take up the significance and purpose of selecting the proper coordinate system from the flat space-time of non-relativistic theories to the quantum theoretic formulation of general relativity. The universal background problem is straight forwardly framed as a momentum-energy portrait in nexus with its space-time conjugates. The description is based on operator matrix algebra, where the related analogue of the secular equation yields a Klein-Gordon type equation and the associated Minkowski eigentime element. The energy-momentum and their conjugate partners are represented by spaces that have (+,−) signatures. The general theory implicates both non-zero- and zero rest-mass entities, and it is proved that the conjugate relationship between energy and time provide a simple derivation of the Schwarzschild line element for the case of a gravitational field outside a spherical non-rotational uncharged mass. This result, indicating the appearance of a black hole as a true singularity in the energy-time formulation, and obtained as a direct consequence of their conjugate relationship, manifests background independence in concert with Einstein’s equivalence principle. Inducing a reformulation of the Lorentz Transformation respecting the indefinite Minkowski metric, displays an interesting relation between complex dilations and indefinite metric spaces, validating the complex symmetric ansatz.

This research selected Z-shaped section column joints in RC frame as the investigating object and considered the mechanical parameters extracted from physical model test results, proposed the finite element model of concrete damaged plasticity. Combining concrete damage plasticity model parameters on ABAQUS of concrete constitutive relationship from appendix C of Code for design of concrete structures (GB50010-2010), add the concept of damage factor to Energy equivalence principle, construct finite element model of Z-shaped column joints in RC frame, and simulated the test process under horizontal cyclic loading. The analysis results indicate that the finite element model can perfectly simulate action. It can reflect the mechanical properties of Z-shaped column joints in frame under horizontal cyclic loading, which is proved correct and reliable.

For equation-error autoregressive (EEAR) systems, this paper proposes an identification algorithm by means of the model equivalence transformation. The basic idea is to eliminate the autoregressive term in the model using the model transformation, to estimate the parameters of the converted system and further to compute the parameter estimates of the original system using the comparative coefficient way and the model equivalence principle. For comparison, the recursive generalized least squares algorithm is given simply. The simulation results verify that the proposed algorithm is effective and can produce more accurate parameter estimates.

International audience; We present several experiments in fundamental physics that use atomic clocks and sensors together with high performance time/frequency transfer methods. Our account is far from being exhaustive and instead concentrates on a chosen subset of present and future experiments, whilst providing some theoretical background. We only give very brief overviews of the experiments and theories, but provide ample references for the interested reader.; Nous présentons plusieurs expériences en physique fondamentale qui utilisent les horloges et les capteurs atomiques en combinaison avec des méthodes de transfert en temps/fréquence de haute performance. Notre revue est loin d'être exhaustive et se concentre plutôt sur un sous-ensemble choisi d'expériences actuelles et futures, tout en fournissant un certain background théorique. Nous nous bornons à donner de brefs survols des expériences et des théories, mais fournissons d'amples références bibliographiques pour le lecteur intéressé par le sujet.

This review describes why the geometric nature of space–time, the Einstein equivalence principle, and the geodesic motion of particles show the possibility of building an extended relativistic theory of gravity on regions where the Tully–Fisher law is valid. It is also shown how a metric construction of gravity can have a modified Newtonian dynamics behaviour compatible with the Tully–Fisher law and the bending of light observed in individual, groups, and clusters of galaxies. It is also reviewed how this metric theory of gravity fits reasonably well on cosmological scales explaining the current acceleration of the universe.

Schrodinger’s wave mechanics is briefly introduced, and its equivalence with the matrix formalism of Heisenberg (and others) is demonstrated.

In this paper, an approximation iterative model based and a semi-empirical approximation model based on equivalence principle in the terahertz gap are described for predicting the bistatic normalized radar cross section of a homogeneous layer made up of two rough interfaces which have the same profiles. The model of two interfaces can be substituted with one interface by replacing the Fresnel reflection coefficients to equivalent reflection coefficients to get the efficiency improved. This model is valid for thin layer and low incidence angles. Results are presented to validate the model by comparison with iterative physical optics.

We study the stretching of a surface-tethered polyelectrolyte confined between parallel surfaces under the application of a dc electric field. We explore the influence of the electric-field strength, the length of the polyelectrolyte, and the degree of confinement on the conformation of the polyelectrolyte by single-molecule experiments and coarse-grained coupled lattice-Boltzmann molecular-dynamics simulations. The fractional extension of the polyelectrolyte is found to be a universal function of the product of the applied electric field and the molecular contour length, which is explained by simple scaling arguments. The degree of confinement does not have any significant influence on the stretching. We also confirm that an electrohydrodynamic equivalence principle relating the stretching in an electric field to that in a flow field is applicable.

This paper provides first results of the investigation of a modular, black box framework for domain deocomposition with regards to the definition of a reliable stopping criterion. The considered framework is based on the surface equivalence principle allowing for the black box approach. But, this in turn leads to the problem of finding an appropriate indicator for the errors in the quantities of interest, which typically are defined locally in the subdomains and are not directly available at the abstract level of the framework itself. First results of a stopping criterion based upon the residual are presented.

Recent results have shown that a field non-minimally coupled to the electromagnetic Lagrangian can induce a violation of the Einstein equivalence principle. { This kind of coupling is present in a very wide class of gravitation theories.} In a cosmological context, this would break the validity of the cosmic distance duality relation as well as cause a time variation of the fine structure constant. Here, we improve constraints on this scenario by using four different observables: the luminosity distance of type Ia supernovae, the angular diameter distance of galaxy clusters, the gas mass fraction of galaxy clusters and the temperature of the cosmic microwave background at different redshifts. We consider four standard parametrizations adopted in the literature and show that, due to a high complementarity of the data, the errors are shrunk between 20\% and 40\% depending on the parametrization. We also show that our constraints are weakly affected by the geometry considered to describe the galaxy clusters. In short, no violation of the Einstein equivalence principle is detected up to redshifts $\sim$ 3., 14 pages, 3 figures, I table, Classical and Quantum Gravity, in press