Energy-Dependent Phenomenological Metrics and Five-Dimensional Einstein Equations

We propose a new Kaluza-Klein-like scheme based on a five-dimensional Riemannian space in which energy plays the role of the fifth dimension and spacetime is deformed. The solutions of the five-dimensional Einstein equations in vacuum allow us to recover, as special cases, the energy-dependent phenomenological metrics, describing the four fundamental interactions, recently derived from the analysis of some experimental data.     

Five-dimensional Relativity with Energy as Extra Dimension

A Kaluza-Klein-like framework is developed infive-dimensional spaces in which the extra dimension isassumed to be the energy of physical processes and thefour-dimensional spacetime is endowed with anenergy-dependent metric. The detailed analysisof some classes of solutions of the (vacuum) Einsteinequations shows that the E = const. slices possessenergy-dependent four-dimensional metrics whichintriguingly reproduce the phenomenologicaldeformed metrics derived from theexperimental data on some physical phenomena ruled bythe four fundamental interactions (electromagnetic,weak, strong and gravitational). This extends previous results concerning theslowing down of clock rates in a gravitational field.Incidentally it is also shown that a special solution ofthe five-dimensional geodesics equation allowsto derive a sort of quantum-mechanicaltime-energy uncertainty relation.     

Remarks on stratifying interactions in five dimensions

A geometric model is proposed in which the interaction types, namely the strong, weak, electromagnetic, and gravitational interactions, are stratified in a five-dimensional manifold. The strong and electromagnetic interactions are confined to disjoint four-spaces and the weak and gravitational interactions are proposed unified in a five-manifold bounded topologically by the strong and electromagnetic four-spaces. Further, some advantages of the five-dimensional approach to current-current interactions are discussed, and a five-dimensional approach to PCAC is presented. The model is presented in hopes of reconciling some contradictory lines of theoretical thought, and new fields for investigation are stressed.     

Five-dimensional teleparallel theory equivalent to general relativity, the axially symmetric solution, energy and spatial momentum

A theory of (4+1)-dimensional gravity is developed on the basis of the teleparallel theory equivalent to general relativity. The fundamental gravitational field variables are the five-dimensional vector fields (pentad), defined globally on a manifold M, and gravity is attributed to the torsion. The Lagrangian density is quadratic in the torsion tensor. We then give the exact five-dimensional solution. The solution is a generalization of the familiar Schwarzschild and Kerr solutions of the four-dimensional teleparallel equivalent of general relativity. We also use the definition of the gravitational energy to calculate the energy and the spatial momentum.     

Statistics of internal excitations of atomic systems

The character of internal excitations is compared for phase transitions and chemical transitions in atomic systems. Although the temperature dependences of some physical parameters of atomic systems have resonance-like structures with maxima in both cases, the dependences of the partition functions on the number of elementary excitations or the excitation energy differ because of the difference in the numbers of interactions that govern the transitions. The phase changes of condensed rare gases are considered in the case where the external pressure is small and the differences between phases are predominantly associated with differences in configurations. Important energy parameters of rare gases are determined by the attractive part of the pairwise interaction potential between atoms. The statistical analysis shows the existence of a “freezing limit” temperature for these systems, below which the liquid state becomes unstable. The kinetics of decay of such unstable states is analyzed in terms of the diffusion of voids.     

Theory of high-harmonic gyrotron oscillators with slottedcross-section structure

A linear-theory analysis of gyrotron oscillators with slotted cross section is used to calculate the net change in beam energy. In this formalism, geometric factors are clearly distinguished from the geometry-independent harmonic resonance terms due to the fundamental electron cyclotron maser and peniotron interactions. This separation of the interaction terms from the geometric factors simplifiers the physical analysis, and leads to a very compact form for the net change in beam energy. The theory is applied to slotted rectangular oscillators and to slotted cylindrical oscillators to show that a unified expression can be obtained for the start-oscillation condition. In sample applications of the theory, it is demonstrated that slots lower the start-oscillation condition in both cylindrical and rectangular geometries, and can lead to a decrease in this condition as harmonic number is increased in the rectangular geometry. It is also found that the peniotron interaction, which is easily identified in this formalism, may be very strong in slotted cavities     

High energy description of dark energy in an approximate 3-brane Brans–Dicke cosmology

We consider a Brans–Dicke cosmology in five-dimensional space–time. Neglecting the quadratic and the mixed Brans–Dicke terms in the Einstein equation, we derive a modified wave equation of the Brans–Dicke field. We show that, at high energy limit, the 3-brane Brans–Dicke cosmology could be described as the standard one by changing the equation of state. Finally as an illustration of the purpose, we show that the dark energy component of the universe agrees with the observations data.     

Identities for the electron forms 2 and their 3D representation

New type of identities for products of the electron forms 2 (Fs2) and the bilinear forms (BFs) are derived. The identities are found for both temporal Fs2 describing the electron energy and quasi energy densities and spatial Fs2 describing the linear momentum and quasi linear momentum densities. The identities allow one to transform the quasi energy densities into the energy densities as well as the quasi linear momentum densities into the linear momentum densities. It is shown that by choosing any one of the 16 electron temporal or spatial Fs2 one can represent the remaining 15 temporal or spatial Fs2 as combinations of a chosen form 2 (F2) and the derivatives of a number of BFs. Any one of such 16 sets of identities can be considered as a specific form of an irreducible representation for the temporal or spatial Fs2. Similar to the bilinear identities for BFs the derived identities can be used for reduction different physical quantities describing the electron to the forms defined by the basic physical observables. As an example we consider transformation of the electron energy density to a new fundamental form that presents the energy density through the linear momentum density.     

Generating physically realizable stellar structures via embedding

In this work we present an exact solution of the Einstein–Maxwell field equations describing compact charged objects within the framework of classical general relativity. Our model is constructed by embedding a four-dimensional spherically symmetric static metric into a five-dimensional flat metric. The source term for the matter field is composed of a perfect fluid distribution with charge. We show that our model obeys all the physical requirements and stability conditions necessary for a realistic stellar model. Our theoretical model approximates observations of neutron stars and pulsars to a very good degree of accuracy.     

Ion–solid interactions: current status,new perspectives

In the past half century, we have witnessed an explosive growth of effort in that cross-discipline which is characterized by the deposition of localized high–energy densities in condensed matter by means of energetic ions—the field of ion–solid interactions. In this overview, the fundamental physical processes of ion–solid interaction are outlined. A brief discussion is given of the basic energy transfer mechanisms and the consequences of ion impact into solids such as scattering, sputtering and radiation damage. It is now understood that radiation damage is itself far from being restricted to deleterious and detrimental consequences. Our knowledge of the growing variety of changes in the physical, chemical and biological properties of target materials are growing exponentially. Many valuable beneficial technological applications, some of which we discuss, have their origin in physical processes taking place at the nanometric level.     

Absence of ferromagnetic long range order in random isotropic dipolar magnets and in similar systems

It is shown that random off-diagonal exchange interaction coefficients destroy ferromagnetic long range order in isotropic systems with less than four spatial dimensions. A special case is that of random isotropic systems with dipole-dipole interactions. The proof breaks down when (cubic or hexagonal) symmetry breaking terms are introduced. However, in some cases such terms turn the transition into the ferromagnetic phase first order, with a possible spin glass phase above it.     

Irreversibility and dissipation in finite-state automata

Irreversibility and dissipation in finite-state automata (FSA) are considered from a physical-information-theoretic perspective. A quantitative measure for the computational irreversibility of finite automata is introduced, and a fundamental lower bound on the average energy dissipated per state transition is obtained and expressed in terms of FSA irreversibility. The irreversibility measure and energy bound are germane to any realization of a deterministic automaton that faithfully registers abstract FSA states in distinguishable states of a physical system coupled to a thermal environment, and that evolves via a sequence of interactions with an external system holding a physical instantiation of a random input string. The central result, which is shown to follow from quantum dynamics and entropic inequalities alone, can be regarded as a generalization of Landauer?s Principle applicable to FSAs and tailorable to specified automata. Application to a simple FSA is illustrated.     

硅熔化特性的分子动力学模拟–-不同势函数的对比研究

分别采用Stillinger-Weber (SW)势、修正的成熟原子嵌入模型(MEAM)势、 Tersoff势和HOEP (highly optimized empirical potential)势来描述硅原子间相互作用, 运用分子动力学方法对比模拟研究了四种势函数的硅晶体的体熔化和表面熔化特性. 结果表明: 四种势函数均能反映出硅的热膨胀、高温熔化和熔化时吸热收缩等基本物理规律. 但综合对比发现, Tersoff势和MEAM势相对更适合描述硅的熔化和凝固过程, SW势次之, HOEP势则不适合描述硅的熔化和凝固过程. 关键词： 硅 势函数 熔化 分子动力学     

The electromagnetic energy with the truncation method for a five-dimensional rotating black hole in a uniform magnetic field

We consider a charged five-dimensional Myers–Perry black hole in a uniform magnetic (test) field. Using the Komar mass formula, we calculate the total energy of the electromagnetic field within the truncation three-sphere for a five-dimensional rotating black hole with two equal-rotation parameters and two equal-magnetic field strengths. We show that the total electromagnetic energy takes the minimum value when the five-dimensional rotating black hole acquires a non-zero net electric charge Q.     

Near horizon data and physical charges of extremal AdS black holes

We compute the physical charges and discuss the properties of a large class of five-dimensional extremal AdS black holes by using the near horizon data. Our examples include baryonic and electromagnetic black branes, as well as supersymmetric spinning black holes. In the presence of the gauge Chern-Simons term, the five-dimensional physical charges are the Page charges. We carry out the near horizon analysis and compute the four-dimensional charges of the corresponding black holes by using the entropy function formalism and show that they match the Page charges.     

Modified gravitational equations on braneworld with Lorentz invariant violation

The modified gravitational equations to describe a four-dimensional braneworld in the case with the Lorentz invariant violation in a bulk spacetime is presented. It contains a trace part of the brane energy-momentum tensor and the coefficients of all terms describe the Lorentz violation effects from the bulk spacetime. As an application, we apply this formalism to study cosmology. In respect to standard effective Friedmann equations on the brane, Lorentz invariance violation in the bulk causes a modification of this equations that can lead to significant physical consequences. In particular, the effective Friedmann equation on the brane explicitly depends on the equation of state of the brane matter and the Lorentz violating parameters. We show that the components of five-dimensional Weyl curvature are related to the matter on brane even at low energies. We also find that the constraints on the theory parameters are depend on the equation of state of the energy components of the brane matter. Finally, the stability of the model depend on the specific choices of initial conditions and the parameters β _i .     

光合作用原初过程能量和电荷超快传递过程原理浅析

文章侧重于从物理的角度,介绍光合作用原初过程中能量和电荷超快传递过程的相关物理化学原理,如费米黄金规则,Frster及Dexter传能机制,Marcus电荷转移理论及激子理论.辨析相关原理的适用范围、共性及差异,并力图在上述相关原理的基础上阐述光合膜蛋结构与功能的关系,勾画出该研究方向的基本脉络.     

Induced Matter and Particle Motion in Non-Compact Kaluza-Klein Gravity

We examine generalizations of the five-dimensional canonical metric by including a dependence of the extra coordinate in the four-dimensional metric. We discuss a more appropriate way to interpret the four-dimensional energy-momentum tensor induced from the five-dimensional space-time and show it can lead to quite different physical situations depending on the interpretation chosen. Furthermore, we show that the assumption of five-dimensional null trajectories in Kaluza-Klein gravity can correspond to either four-dimensional massive or null trajectories when the path parameterization is chosen properly. Retaining the extra-coordinate dependence in the metric, we show the possibility of a cosmological variation in the rest masses of particles and a consequent departure from four-dimensional geodesic motion by a geometric force. In the examples given, we show that at late times it is possible for particles traveling along 5D null geodesics to be in a frame consistent with the induced matter scenario.     

Black holes in brane worlds

A Kerr metric describing a rotating black hole is obtained on the three brane in a five-dimensional Randall-Sundrum brane world by considering a rotating five-dimensional black string in the bulk. We examine the causal structure of this space-time through the geodesic equations.