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101.
采用非平衡过程动力学理论,考虑核反应区对流、扩散及引力的影响.对He4燃烧有不考虑引力影响时,扩散效应是体系的稳定因素;(△) ·V→>0时的对流效应是体系的稳定因素;核反应本身处于临界稳定状态;引力效应存在一临界半径rc,r<rc和r>rc分别为系统的稳定和不稳定因素.但综合以上所有效应,系统是稳定的,且涨落的模数越大,定态的稳定性程度越高. 相似文献
102.
Howard E. Brandt 《Foundations of Physics Letters》2004,17(3):295-300
One implication of maximal proper acceleration is an intrinsic regularization of quantum fields which depends on the universal
gravitational constant. It also follows that the vacuum energy density, seen by any one observer, is finite. 相似文献
103.
Christopher Kohler 《General Relativity and Gravitation》2000,32(7):1301-1317
A class of theories of gravitation that naturally incorporates preferred frames of reference is presented. The underlying space-time geometry consists of a partial parallelization of space-time and has properties of Riemann—Cartan as well as teleparallel geometry. Within this geometry, the kinematic quantities of preferred frames are associated with torsion fields. Using a variational method, it is shown in which way action functionals for this geometry can be constructed. For a special action the field equations are derived and the coupling to spinor fields is discussed. 相似文献
104.
In previous work it has been shown that the electromagnetic quantum vacuum, or electromagnetic zero‐point field, makes a contribution to the inertial reaction force on an accelerated object. We show that the result for inertial mass can be extended to passive gravitational mass. As a consequence the weak equivalence principle, which equates inertial to passive gravitational mass, appears to be explainable. This in turn leads to a straightforward derivation of the classical Newtonian gravitational force. We call the inertia and gravitation connection with the vacuum fields the quantum vacuum inertia hypothesis . To date only the electromagnetic field has been considered. It remains to extend the hypothesis to the effects of the vacuum fields of the other interactions. We propose an idealized experiment involving a cavity resonator which, in principle, would test the hypothesis for the simple case in which only electromagnetic interactions are involved. This test also suggests a basis for the free parameter η(ν) which we have previously defined to parametrize the interaction between charge and the electromagnetic zero‐point field contributing to the inertial mass of a particle or object. 相似文献
105.
Amitava Datta 《Pramana》2000,55(1-2):183-193
In this brief review the following topics are discussed:
Direct searches for SUSY in mSUGRA: a brief review of the relevant mass limits, the clean trilepton signal, the hunt for the
third generation of sfermions,
Direct searches beyond mSUGRA: search prospects in models with nonuniversal gaugino masses, search prospects in models with
nonuniversal scalar masses,
Indirect searches for SUSY: precision electroweak observables and SUSY, ε′/ε and SUSY. 相似文献
106.
Wei Wang Yong-jian Yang Lian-sheng Zhang 《应用数学学报(英文版)》2007,23(1):59-66
In this paper,two auxiliary functions for global optimization are proposed.These two auxiliaryfunctions possess all characters of tunnelling functions and filled functions under certain general assumptions.Thus,they can be considered as the unification of filled function and tunnelling function.Moreover,the processof tunneling or filling for global optimization can be unified as the minimization of such auxiliary functions.Result of numerical experiments shows that such two auxiliary functions are effective. 相似文献
107.
Jogesh C. Pati 《Pramana》2003,60(2):291-336
It is noted that a set of facts points to the relevance in four dimensions of conventional supersymmetric unification based
on minimally a string-unifiedG(224) symmetry, or maximallySO(10). These include: (i) the observed family structure, (ii) quantization of electric charge, (iii) meeting of the three gauge
couplings, (iv) neutrino oscillations (in particular the value of δm
2(νμ−δ
τ), suggested by SuperK), (v) the intricate pattern of the masses and mixings of the fermions, including the smallness ofV
cb and the largeness ofθ
μνμτ
osc
, and (vi) the need for B-L as a generator to implement baryogenesis (via leptogenesis). A concrete proposal is presented
within a predictiveSO(10)/G(224) framework that successfully describes the masses and mixings of all fermions, including the neutrinos — with eight predictions,
all in agreement with observation. Within this framework, a systematic study of proton decay is carried out, which (a) pays
special attention to its dependence on the fermion masses, (b) limits the threshold corrections so as to preserve natural
coupling unification, and (c) uses recently improved values of the matrix element and renormalization effects. Allowing for
both minimal supersymmetric standard model (MSSM) and its proposed variant, the so-called extended supersymmetric standard
model (ESSM), as effective low-energy the ories, the study shows that a conservative upper limit on the proton lifetime is
about (l–2)× 1034 years, with ·−K+ being the dominant decay mode, and quite possibly μ+
K
0 ande
+π0 being prominent. This in turn strongly suggests that an improvement in the current sensitivity by a factor of five to ten
ought to reveal proton decay. For comparison, some alternatives to the conventional approach to unification pursued here are
mentioned at the end.
Invited paper presented at the International Summer School held at ICTP, Trieste (June, 2001) and at WHEPP-7 Conference, Allahabad,
India (January, 2002). This is an updated version of the paper presented at the Erice School (September, 2000), hep-ph/0106082. 相似文献
108.
根据引力场和静电场的相似性质,通过类比方法由静电场的麦克斯韦应力张量得出了引力场中的应力张量,并用它计算均质球体内部的万有引力。 相似文献
109.
The multifractal spectrum of various three-dimensional representations of Packed Swiss Cheese cosmologies in open, closed, and flat spaces are measured, and it is determined that the curvature of the space does not alter the associated fractal structure. These results are compared to observational data and simulated models of large scale galaxy clustering, to assess the viability of the PSC as a candidate for such structure formation. It is found that the PSC dimension spectra do not match those of observation, and possible solutions to this discrepancy are offered, including accounting for potential luminosity biasing effects. Various random and uniform sets are also analyzed to provide insight into the meaning of the multifractal spectrum as it relates to the observed scaling behaviors. 相似文献
110.
Alexander B. Balakin 《General Relativity and Gravitation》2004,36(7):1513-1525
A new exactly solvable model for the evolution of a relativistic kinetic system interacting with an internal stochastic reservoir under the influence of a gravitational background expansion is established. This model of self-interaction is based on the relativistic kinetic equation for the distribution function defined in the extended phase space. The supplementary degree of freedom is described by the scalar stochastic variable (Langevin source), which is considered to be the constructive element of the effective one-particle force. The expansion of the Universe is shown to be accelerated for the suitable choice of the non-minimal self-interaction force. 相似文献