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11.
在e-A深度非弹性散射过程中, 喷注穿过冷核介质时, 多重散射诱导胶子辐射会导致对碎裂函数的修正及喷注的能量损失.前期研究中关于计算e-A深度非弹性散射中胶子辐射振幅的两种方法: 螺旋振幅近似和微扰QCD严格计算都异常繁杂.
本文发展了一种新的方法, 可以方便计算出多重散射导致胶子辐射的振幅, 得到的碎裂函数的修正以及能量损失与严格计算的结果一致. 相似文献
12.
YAN Zhen-Ya 《理论物理通讯》2002,38(10)
Recently, we obtained thirteen families of Jacobian elliptic function solutions of mKdV equation by usingour extended Jacobian elliptic function expansion method. In this note, the mKdV equation is investigated and anotherthree families of new doubly periodic solutions (Jacobian elliptic function solutions) are fbund again by using a newtransformation, which and our extended Jacobian elliptic function expansion method form a new method still called theextended Jacobian elliptic function expansion method. The new method can be more powertul to be applied to othernonlinear differential equations. 相似文献
13.
Barotropic FRW cosmologies are presented from the standpoint of nonrelativistic supersymmetry. First, we reduce the barotropic FRW system of differential equations to simple harmonic oscillator differential equations. Employing the factorization procedure, the solutions of the latter equations are divided into the two classes of bosonic (nonsingular) and fermionic (singular) cosmological solutions. We next introduce a coupling parameter denoted by K between the two classes of solutions and obtain barotropic cosmologies with dissipative features acting on the scale factors and spatial curvature of the universe. The K-extended FRW equations in comoving time are presented in explicit form in the low coupling regime. The standard barotropic FRW cosmologies correspond to the dissipationless limit K = 0. 相似文献
14.
Hans J. Fahr 《Foundations of Physics Letters》2006,19(5):423-440
According to ideas of Mach, Whitrow, Dirac, or Hoyle, inertial masses of particles should not be a genuine, predetermined
quantity; rather they should represent a relational quantity which by its value somehow reflects the deposition and constellation
of all other objects in their cosmic environment. In this paper we want to pick up suggestions given by Thirring and by Hoyle
of how, due to requirements of the equivalence of rotations and of general relativistic conformal scale invariance, the particle
masses of cosmic objects should vary with the cosmic length scale. We study cosmological consequences of comoving cosmic masses
which co-evolve by mass with the expansion of the universe. The vanishing of the covariant divergence of the cosmic energy-momentum
tensor under the new prerequisite that matter density only falls off with the reciproke of the squared cosmic scale S(t) then leads to the astonishing result that cosmic pressuredoes not fall off adiabatically but rather falls off in a quasi-isothermal
behaviour, varying with S(t) as matter density does. Hence, as a new cosmological fact, it arises that, even in the late phases of cosmic expansion,
pressure cannot be neglected what concerns its gravitational action on the cosmic dynamics. We then show that under these
conditions the cosmological equations can, however, only be solved if, in addition to matter, also pressure and energy density
of the cosmic vacuum are included in the calculation. An unaccelerated expansion with a Hubble parameter falling off with
S(t)−1 is obtained for a vacuum energy density decay according to S(t)−2 with a well-tuned proportion of matter and vacuum pressures. As it appears from these results, a universe with particle masses
increasing with the cosmic sale S(t) is in fact physically conceivable in an energetically consistent manner, if vacuum energy at the expansion of the universe
is converted into mass density of real matter with no net energy loss occuring. This universe in addition also happens to
be an economical one which has and keeps a vanishing total energy. 相似文献
15.
N. A. Koshelev 《General Relativity and Gravitation》2004,36(7):1625-1640
The inflationary models based on the non-linear sigma model with the self-coupling potential are considered. The slow-roll solutions for long-wavelength inhomogeneities in general two-component chiral models and diagonal three-component chiral model of a special case are obtained. Scalar perturbations are calculated for two examples. 相似文献
16.
YAN Zhen-Ya 《理论物理通讯》2003,39(2)
More recently, sixteen families of Jacobian elliptic function solutions of mKdV equation have been foundby using our extended Jacobian elliptic function expansion method. In this paper, we continue to improve our methodby using another eight pairs of the closed Jacobian elliptic functions. The mKdV equation is chosen to illustrate theimproved method such that another eight families of new Jacobian elliptic function solutions are obtained again. Thenew method can be more powerful to be applied to other nonlinear differential equations. 相似文献
17.
18.
New Exact Solutions to the Combined KdV and mKdV Equation 总被引:2,自引:0,他引:2
Yan-ze Peng 《International Journal of Theoretical Physics》2003,42(4):863-868
The modified mapping method is developed to obtain new exact solutions to the combined KdV and mKdV equation. The method is applicable to a large variety of nonlinear evolution equations, as long as odd- and even-order derivative terms do not coexist in the equation under consideration. 相似文献
19.
20.
P. Q. Khanh 《Journal of Optimization Theory and Applications》1995,87(2):359-378
We prove the Kuhn-Tucker sufficient optimality condition, the Wolfe duality, and a modified Mond-Weir duality for vector optimization problems involving various types of invex-convexlike functions. The class of such functins contains many known generalized convex functions. As applications, we demonstrate that, under invex-convexlikeness assumptions, the Pontryagin maximum principle is a sufficient optimality condition for cooperative differential games. The Wolfe duality is established for these games.The author is indebted to the referees and Professor W. Stadler for valuable remarks and comments, which have been used to revise considerably the paper. 相似文献