A Re-interpretation of the Concept of Mass and of the Relativistic Mass-Energy Relation

For over a century the definitions of mass and derivations of its relation with energy continue to be elaborated, demonstrating that the concept of mass is still not satisfactorily understood. The aim of this study is to show that, starting from the properties of Minkowski spacetime and from the principle of least action, energy expresses the property of inertia of a body. This implies that inertial mass can only be the object of a definition—the so called mass-energy relation—aimed at measuring energy in different units, more suitable to describe the huge amount of it enclosed in what we call the “rest-energy” of a body. Likewise, the concept of gravitational mass becomes unnecessary, being replaceable by energy, thus making the weak equivalence principle intrinsically verified. In dealing with mass, a new unit of measurement is foretold for it, which relies on the de Broglie frequency of atoms, the value of which can today be measured with an accuracy of a few parts in 10⁹.     

The Effect of the Relative Motion of Atoms on the Frequency of the Emitted Light and the Reinterpretation of the Ives-Stilwell Experiment

We examine the process of the emission of light from an atom that is in a relative translational motion with respect to the medium at rest in which the electromagnetic excitations propagate. The effect of Lorentz contraction of the of electron orbits on the emitted frequency is incorporated in the Rydberg formula, as well as the emitter’s Doppler effect is acknowledged. The result is that the frequency of the emitted light is modified by a factor that is identical with what is called the ‘relativistic Doppler effect’. The new emission formula is applied for reinterpretation of the Ives-Stilwell experiment and shown that within the second order of approximation with respect to the speeds of the atom and the ‘absolute speed’ (Earth’s speed relative to the medium), the absolute motion does not affect the interference. The expression for the modification of the frequency involves both a first and a second-order term with respect to the speed of the atoms in the cathode tube. The latter turns out to be quantitatively the same as if the time would have changed its rate in the frame moving with the atoms. Thus, a new interpretation of the results of this famous experiment is provided without stipulating time dilation.     

Viscosity of argon to 5 GPa and 673 K

A rolling-sphere technique has been used to measure shear viscosities of (supercritical) fluid argon in the diamond-anvil cell between the temperatures of 294 and 673 K, up to a maximum pressure of 5 GPa. At these pressures, the viscosities can be fit to a modified free-volume expression. A single correlation between reduced viscosity and reduced residual entropy is shown to give a good account of the current high pressure data, data at lower pressures and those for the sub-critical liquid.     

Nonequilibrium Thermodynamics of the First and Second Kind: Averages and Fluctuations

We elaborate and compare two approaches to nonequilibrium thermodynamics, the two-generator bracket formulation of time-evolution equations for averages and the macroscopic fluctuation theory, for a purely dissipative isothermal driven diffusive system under steady state conditions. The fluctuation dissipation relations of both approaches play an important role for a detailed comparison. The nonequilibrium Helmholtz free energies introduced in these two approaches differ as a result of boundary conditions. A Fokker-Planck equation derived by projection operator techniques properly reproduces long range fluctuations in nonequilibrium steady states and offers the most promising possibility to describe the physically relevant fluctuations around macroscopic averages for time-dependent nonequilibrium systems.     

Spontaneous Resonances and the Coherent States of the Queuing Networks

We present an example of a highly connected closed network of servers, where the time correlations do not vanish in the infinite volume limit. The limiting interacting particle system behaves in a periodic manner. This phenomenon is similar to the continuous symmetry breaking at low temperatures in statistical mechanics, with the average load playing the role of the inverse temperature.     

Review of searches for Higgs bosons and beyond the Standard Model Physics at the Tevatron

The energy frontier is currently at the Fermilab Tevatron accelerator, which collides protons and antiprotons at a center-of-mass energy of 1.96 TeV. The luminosity delivered to the CDF and DØ experiments has now surpassed the 4 fb^?1. This paper reviews the most recent direct searches for Higgs bosons and beyond-the-standard-model (BSM) physics at the Tevatron. The results reported correspond to an integrated luminosity of up to 2.5 fb^?1 of Run II data collected by the two Collaborations. Searches covered include the standard model (SM) Higgs boson (including sensitivity projections), the neutral Higgs bosons in the minimal supersymmetric extension of the standard model (MSSM), charged Higgs bosons and extended Higgs models, supersymmetric decays that conserve or violate R-parity, gauge-mediated supersymmetric breaking models, long-lived particles, leptoquarks, compositeness, extra gauge bosons, extra dimensions, and finally signature-based searches. Given the excellent performance of the collider and the continued productivity of the experiments, the Tevatron physics potential looks promising for discovery with the coming larger data sets. In particular, evidence for the SM Higgs boson could be obtained if its mass is light or near 160 GeV. The observed (expected) upper limits are currently a factor of 3.7 (3.3) higher than the expected SM Higgs boson cross section at m _H =115 GeV and 1.1 (1.6) at m _H =160 GeV at 95% C.L.     

Suppression of the Spiral Wave and Turbulence in the Excitability-Modulated Media

Periodical forcing is used to control the spiral wave and turbulence in the modified Fithzhugh-Nagumo equation (MFHNe) when excitability is changed. The decisive parameter ε of (MFHNe), which describes the ratio of time scales of the fast activator u and the slow inhibitor variable v, is supposed to increase linearly to simulate the excitability modulation in the media. In the numerical simulation, a local periodical stimulus is imposed on the left border of the media and the periods of external forcing are adjusted according to the approximate formula ω ∝1/ε ^1/3 so that using the most appropriate frequency for the external forcing can approach a shorter transient period. It is found that the spiral wave and turbulence can be removed successfully by using an appropriate periodical forcing on the left border of the media. The mean activator and distribution of frequency of all the sites are also used to analyze the transition of spiral wave.     

Chaos and Monte Carlo Approximations of the Flip-Annihilation process

The flip-annihilation process is a random particle process with one-dimensional local interaction in discrete time, initially presented by one of us, namely Toom in 2004. Its components are enumerated by integer numbers and every component has two states, “minus” and “plus”. At every time step two transformations occur. The first one, called “flip”, independently turns every minus into plus with probability β. The second one, called “annihilation”, acts thus: whenever a plus is a left neighbor of a minus, both disappear with probability α independently from other components. What is interesting about this process is that it is ergodic for β>α/2 and non-ergodic for β<α ²/250. It is natural to conjecture that there is some transition curve, which we call the true curve and denote by , which separates the areas of ergodicity and non-ergodicity of this process from each other. The estimates, mentioned above, albeit rigorous, leave a large gap between them and the present article’s purpose is to obtain some closer, albeit non-rigorous, approximations of the true curve. We do it in two ways, one of which is a chaos approximation and the other is a Monte Carlo simulation. Thus we obtain two curves, which are much closer to each other than the rigorous estimations. Also we fill in, albeit only numerically, another shortcoming of the rigorous estimation β<α ²/250, namely that it leaves us uncertain whether the true curve has a zero or positive slope at the point α=β=0. Both approximate curves have a positive slope at α=0, as we hoped.     

Discrete Spectrum of the Deficit Angle and the Differential Structure of a Cosmic String

Differential properties of Klein-Gordon and electromagnetic fields on the space-time of a straight cosmic string are studied with the help of methods of the differential space theory. It is shown that these fields are smooth in the interior of the cosmic string space-time and that they loose this property at the singular boundary except for the cosmic string space-times with the following deficit angles: Δ=2π(1−1/n), n=1,2,… . A connection between smoothness of fields at the conical singularity and the scalar and electromagnetic conical bremsstrahlung is discussed. It is also argued that the smoothness assumption of fields at the singularity is equivalent to the Aliev and Gal’tsov “quantization” condition leading to the above mentioned discrete spectrum of the deficit angle.     

Three Slit Experiments and the Structure of Quantum Theory

In spite of the interference manifested in the double-slit experiment, quantum theory predicts that a measure of interference defined by Sorkin and involving various outcome probabilities from an experiment with three slits, is identically zero. We adapt Sorkin’s measure into a general operational probabilistic framework for physical theories, and then study its relationship to the structure of quantum theory. In particular, we characterize the class of probabilistic theories for which the interference measure is zero as ones in which it is possible to fully determine the state of a system via specific sets of ‘two-slit’ experiments.     

The Foundations of Quantum Mechanics and the Evolution of the Cartan-Kähler Calculus

In 1960–1962, E. Kähler enriched É. Cartan’s exterior calculus, making it suitable for quantum mechanics (QM) and not only classical physics. His “Kähler-Dirac” (KD) equation reproduces the fine structure of the hydrogen atom. Its positron solutions correspond to the same sign of the energy as electrons. The Cartan-Kähler view of some basic concepts of differential geometry is presented, as it explains why the components of Kähler’s tensor-valued differential forms have three series of indices. We demonstrate the power of his calculus by developing for the electron’s and positron’s large components their standard Hamiltonian beyond the Pauli approximation, but without resort to Foldy-Wouthuysen transformations or ad hoc alternatives (positrons are not identified with small components in K ähler’s work). The emergence of negative energies for positrons in the Dirac theory is interpreted from the perspective of the KD equation. Hamiltonians in closed form (i.e. exact through a finite number of terms) are obtained for both large and small components when the potential is time-independent. A new but as yet modest new interpretation of QM starts to emerge from that calculus’ peculiarities, which are present even when the input differential form in the Kähler equation is scalar-valued. Examples are the presence of an extra spin term, the greater number of components of “wave functions” and the non-association of small components with antiparticles. Contact with geometry is made through a Kähler type equation pertaining to Clifford-valued differential forms.     

Dynamics of tachyon and phantom field beyond the inverse square potentials

We investigate the cosmological evolution of the tachyon and phantom-tachyon scalar field by considering the potential parameter $\Gamma(=\frac{VV''}{V'^{2}}$ ) as a function of another potential parameter $\lambda(=\frac{V'}{\kappa V^{3/2}}$ ), which correspondingly extends the analysis of the evolution of our universe from a two-dimensional autonomous dynamical system to the three-dimensional case. It allows us to investigate the more general situation where the potential is not restricted to an inverse square potential. One particular result is that, apart from the inverse square potential, there are a large number of potentials which can give the scaling and dominant solution when the function Γ(λ) equals 3/2 for one or more values of λ _*, as well as that the parameter λ _* satisfies certain conditions. We also find that for a class of different potentials the possibilities for the dynamical evolution of the universe are actually the same and therefore undistinguishable.     

On the Electromagnetic Origin of Inertia and Inertial Mass

We address the problem of inertial property of matter through analysis of the motion of an extended charged particle. Our approach is based on the continuity equation for momentum (Newton’s second law) taking due account of the vector potential and its convective derivative. We obtain a development in terms of retarded potentials allowing an intuitive physical interpretation of its main terms. The inertial property of matter is then discussed in terms of a kind of induction law related to the extended charged particle’s own vector potential. Moreover, it is obtained a force term that represents a drag force acting on the charged particle when in motion relatively to its own vector potential field lines. The time rate of variation of the particle’s vector potential leads to the acceleration inertia reaction force, equivalent to the Schott term responsible for the source of the radiation field. We also show that the velocity dependent term of the particle’s vector potential is connected with the relativistic increase of mass with velocity and generates a longitudinal stress force that is the source of electric field lines deformation. In the framework of classical electrodynamics, we have shown that the electron mass has possibly a complete electromagnetic origin and the obtained covariant equation solves the “4/3 mass paradox” for a spherical charge distribution.     

Generalized Brans-Dicke Cosmology in the Presence of Matter and Dark Energy

We study the Generalized Brans-Dicke cosmology in the presence of matter and dark energy. Of particular interest for a constant Brans-Dicke parameter, the de Sitter space has also been investigated.     

Effect of Ta buffer layer and TaO x barrier thickness on the evolution of the structural and magnetic properties of the Fe/TaO x /Co trilayers

Fe/TaO _x /Co trilayers were grown on Si(100)/SiO₂ substrates and on tantalum buffer layers by a high vacuum magnetron sputtering system. The effects of both Ta buffer layer and tantalum-oxide barrier layer thickness on the structural and magnetic properties and the coupling of the ferromagnetic layers have been studied. It was observed that Ta improves the structural properties of the Fe layer resulting in an increased coercive field. For a barrier thickness of 4 nm a weak decoupling starts to appear between the ferromagnetic layers and a clear step formation is observed with increasing thickness. The minor hysteresis loops predict an interlayer coupling for thin barriers. The annealing of trilayers up to 250°C shows an increased coercivity for only the Fe layer. Annealing further at 400°C has the opposite effect of decreasing the coercivity, indicating intermixing at the interfaces of the Fe. The refractive index of the insulator barrier shows that the barrier layer is not totally in the form of tantalum-pentoxide.     

Nonlinear coefficient and temperature dependence of the refractive index of lithium niobate crystals in the terahertz regime

The effective nonlinear coefficient d _eff of lithium niobate is determined to be 94 pm/V for a process that converts infrared light to 1.35 THz radiation. This value is inferred from the performance of a continuous-wave, singly-resonant optical parametric oscillator, in which the cavity-enhanced signal wave of a primary parametric process acts as a pump wave for a cascaded process, generating terahertz waves. To quantify the nonlinear coefficient, the coupled wave equations including absorption are evaluated. Furthermore, from our measurements we also determine the temperature dependence of the refractive index to be dn _THz/dT=0.0013/K around 1.4 THz.     

Analysis of the pseudoscalar partner of the Y(4660) and related bound states

In this article, we study the pseudoscalar bound state η _c ′f ₀(980) (irrespective of the hadro-charmonium and the molecular state) with the QCD sum rules. Considering the SU(3) symmetry of the light flavor quarks and the heavy quark symmetry, we also study the bound states η _c ′σ(400?1200), η _b '''f ₀(980) and η _b '''σ(400?1200), and make reasonable predictions for their masses.     

Tri-meson mixing of π–η–η′ and ρ–ω–φ in the light-cone quark model

The radiative transition form factors of the pseudoscalar mesons π, η, η′ and the vector mesons ρ, ω, φ are restudied with π–η–η′ and ρ–ω–φ in the tri-meson-mixing pattern, which is described by tri-mixing matrices in the light-cone constituent quark model. The experimental transition decay widths are better reproduced with tri-meson mixing than previous results in a two-mixing-angle scenario of only two-meson η–η′ mixing and ω–φ mixing.