On the onset of chaotic motion in terms of generalized Langevin equations

New theoretical insights into the generalized Langevin approach to the onset of chaos are given. To make it possible to compare theory with “experiments” a fast computer algorithm is set up.     

Fractal structures in a generalized square map with exponential terms

Fractal structures in a generalized squared map with exponential terms are expanded in this paper. We describe how complex behaviors can arise as the parameters change. The appearances of different kinds of fractal structures, in both the attractive and the divergent regions, and most interestingly, on small regular islands embedded in the chaotic region, are manifested to have a variety of extraordinary geometries in the parameter plane.     

Fractal structures in a generalized square map with exponential terms

Fractal structures in a generalized squared map with exponential terms are expanded in this paper.We describe how complex behaviors can arise as the parameters change.The appearances of different kinds of fractal structures,in both the attractive and the divergent regions,and most interestingly,on small regular islands embedded in the chaotic region,are manifested to have a variety of extraordinary geometries in the parameter plane.     

On a generalization of the Gibbs equation for heat conduction

A generalized Gibbs equation for the heat conduction problem is proposed in order to take finite wave speed into account.     

The improved sub-ODE method for a generalized KdV-mKdV equation with nonlinear terms of any order

In this Letter, Li and Wang's sub-ODE method [X.Z. Li, M.L. Wang, Phys. Lett. A 361 (2007) 115] is improved and applied to the generalized KdV-mKdV equation with nonlinear terms of any order. As a result, more travelling wave solutions are obtained including not only all the known solutions found by Li and Wang but also other formal solutions. This improved sub-ODE method can be used for solving other nonlinear partial differential equations with nonlinear terms of any order in mathematical physics.     

Integrals of generalized Hamilton systems with additional terms

Two kinds of integrals of generalized Hamilton systems with additional terms are discussed. One kind is the integral deduced by Poisson method; the other is Hojman integral obtained by Lie symmetry.     

On a generalized metric

Various invariant theories concerning algebraic properties of four-dimensional space-times have been developed in which the theory of the Debever-Penrose directions and that of Petrov's or Synge's classification belong to the same category. These two algebraic problems have been dealt with in a generalized metric recently considered by the author in studying the wave solutions.     

On a generalization of the equations of electrodynamics

Both the field equations and the equations of motion of a charged particle in an electromagnetic field are generalized. The sense of the generalization consists in giving up the Lorentz condition on the field potentials. The basic conclusion is that, in addition to the charge and mass, the proper rotation of the particle (the spin) should belong to the characteristics of a particle in classical electrodynamics.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 107–110, July, 1972.The author wishes to thank the participants of the Ivanov Inter-Institute Seminar on Mathematical and Theoretical Physics for discussion of the results of the present work.     

A set of new three-parameter entropies in terms of a generalized incomplete Gamma function

In this paper, by considering the first three Khinchin axioms (K1–K3) and neglecting the fourth (K4), a set of new three-parameter entropies will be introduced which are expressed in terms of a generalized incomplete Gamma function as _Sd,c1,c2[p]∝_∑iΓ(d+1,1−_c1ln_pi,1−_c2ln_pi)$S_{d,c_1,c_2}\left[p\right]\propto {\sum }_i\Gamma (d+1,1-c_{1}ln{p}_i,1-c_{2}ln{p}_i)$. Also, its asymptotic behavior will be found and it will be shown that, for some special values of parameters, some known entropies like Tsallis, Kaniadakis and Abe entropies are recovered.     

带有附加项的广义Hamilton系统的Mei对称性

研究带附加项的广义Hamilton系统的Mei对称性的定义和判据，给出系统Mei对称性为Lie对称性的充分必要条件. 通过Lie对称性间接导出具有Mei对称性且带有附加项的广义Hamilton系统运动微分方程的Hojman守恒量. 举例说明结果的应用. 关键词： 附加项 广义Hamilton系统 Mei对称性 Hojman守恒量     

Comparison of solvers for the generalized Riemann problem for hyperbolic systems with source terms

We compare four different approximate solvers for the generalized Riemann problem (GRP) for non-linear systems of hyperbolic equations with source terms. The GRP is a special Cauchy problem for a hyperbolic system with source terms whose initial condition is piecewise smooth. We briefly review the four solvers currently available and carry out a systematic assessment of these in terms of accuracy and computational efficiency. These solvers are the building block for constructing high-order numerical schemes of the ADER type for solving the general initial-boundary value problem for inhomogeneous systems in multiple space dimensions, in the frameworks of finite volume and discontinuous Galerkin finite element methods.     

Continuous growth models in terms of generalized logarithm and exponential functions

Consider the one-parameter generalizations of the logarithmic and exponential functions which are obtained from the integration of non-symmetrical hyperboles. These generalizations coincide to the one obtained in the context of non-extensive thermostatistics. We show that these functions are suitable to describe and unify the great majority of continuous growth models, which we briefly review. Physical interpretation to the generalization function parameter is given for the Richards’ model, which has an underlying microscopic model to justify it.     

Scattering solutions to non-local Hamiltonians in terms of generalized Bessel-Neumann series

We develop and test a method for the numerical solution of partial-wave scattering equations with partially non-local potentials, as arising in microscopic theories of the nucleus-nucleus interaction. The method is complementary to the usual Robertson discretization in that the amount of computation required decreases with increasing energy. It is based on a Bessel-Neumann expansion of the x-space scattering wave function and on its analogue for Coulomb functions. As a by-product, we obtain a new, general representation of the half-off-shell t-matrix and discuss the class of special functions arising in this context.     

On a phase transition for semitransparent materials in terms of the Stefan problem

The paper deals with justification of the formula for the latent heat of phase transition of the first kind, taking into account superheating and subcooling of the formed two-phase system, in application to the solution of Stefan problem in semitransparent materials.     

On a generalization of the hidden symmetry transformations for the principal chiral model

Nonlocal hidden symmetry transformations with a generalized structure and boundary conditions at spatial infinity for the principal chiral model are proposed. Additional restrictions on these transformations following from the requirement for the existence of an infinite set of conserved nonlocal charges are analyzed. The corresponding Lie algebra is more general than the Kac-Moody one.     

An optical system with aberrations on diffraction integrals written in terms of a generalized ABCD matrix

Abstract: In this paper, we consider the transformation of a ray beam as it passes through an optical system containing a glass plate with parallel surfaces inclined to the optical axis at the Brewster’s angle, by investigating the effects of the optical system on amplitude and phase distributions. By applying generalized matrix optics and diffraction integrals and considering the influence of a quarter of a wavelength of aberration on the transmitted amplitude and phase distributions at the focus of a de-collimating lens, we find that the central peak amplitude descends from 1.0 to 0.8 and the phase distortion is less than π/2. The general feature of the amplitude distribution shows an elongation along the y-axis perpendicular to the optical axis in the direction of tilt of the inclined plate, and conforms to the inclination direction of the glass plate.      

含弛豫项的广义光学Bloch方程的近似解

本文用叠代法求得了含弛豫项的广义光学Bloch方程的近似解。与计算机给出的数值积分解的比较表明,一阶叠代解具有足够好的精度。由此得出了上能级占有几率随时间变化的解析表达式及多光子吸收、Bloch-Siegert频移等有用结果。     

Travelling wave solutions for generalized symmetric regularized long-wave equations with high-order nonlinear terms

Applying the general projective Riccati equations method, we consider the exact travelling wave solutions for generalized symmetric regularized long-wave equations with high-order nonlinear terms using symbolic computation.From our results, we not only can successfully recover some previously known travelling wave solutions found by using various tanh methods, but also can obtain some new formal solutions. The solutions obtained include kink-shaped solitons, bell-shaped solitons, singular solitons and periodic solutions.     

准坐标下广义非保守系统Lagrange方程的积分因子与守恒定理

用积分因子方法研究准坐标下广义非保守系统Lagrange方程的守恒定理.列写系统的运动微分方程，给出它的积分因子的定义.研究守恒量存在的必要条件.建立系统的守恒定理及其逆定理，并举例说明结果的应用. 关键词： 准坐标 Lagrange方程 积分因子 守恒量