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91.
A possible unification model for all basic forces   总被引:1,自引:0,他引:1  
A unification model for strong, electromagnetic, weak and gravitational forces is proposed. The tangent space of ordinary coordinate 4-dimensional spacetime is a submanifold of a 14-dimensional internal spacetime spanned by four frame fields. The unification of the standard model with gravity is governed by gauge symmetry in the internal spacetime. Project supported in part by the Outstanding Young Scientist Fund of China.  相似文献   
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A scheme of symmetry breakage can be imposed on orthogonal directed line elements for the algebra sl(4, C) which, for subalgebras, results in a pattern corresponding to the fundamental particles of the standard model, the graviton, and further elements corresponding to possible fundamental particles for dark matter.  相似文献   
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The motion of a particle in a static, spherically symmetric gravitational field is investigated in Euclidean space. The gravitational effects are described as due to a scalar field: To every point in space there is assigned a refractive index deciding the velocity of light in that point. The motion of light in the vacuum is described by the equation of classical optics. An equation of motion for material test particles is then derived by employing the usual Lagrangian formalism. The motion of the planets around the sun is explained, in particular the perihelion motion of Mercury. The present theory fully explains the four classical tests of general relativity in a mathematically far simpler way, and it can be equivalent to the Schwarzschild solution. It is also found that the effect of gravitation depends on the velocity of the particle, becoming repulsive for radial velocities larger thanc/ (c is the velocity of light). This seemingly odd result can also be obtained from the equations of general relativity, as was shown by Cavalleri and Spinelli.  相似文献   
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In the context of the causal interpretation of quantum mechanics one can formulate the equation of motion of a quantal particle in the presence of a gravitational field. It is pointed out that, in the WKB limit of high quantum numbers, states exist for which one component of classical equivalence (that all bodies fall at an equal rate independent of their mass) is not recovered, due to quantum effects mediated by the quantum potential.1. The classical limit of the uncertainty relations is obtained when part of the quantum stress tensor of the field may be neglected - it is not necessary or necessarily consistent to let h 0 here either [3].2. In the relativistic case, one can nevertheless still geometrize quantum mechanics in the presence of gravity by introducing metrics that depend on particle characteristics (e.g. Finsler metric). The equation of motion is then a geodesic in this generalized space [8,9].  相似文献   
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时间标度与甚早期宇宙疑难问题   总被引:2,自引:2,他引:0  
注意到绝对时间和绝对温标分别是在牛顿第二定律和卡诺定理引理成立的前提下所确立的时标和温标,则引力理论方程与大统一理论的动力学方程,比如关于电磁学的麦克斯韦方程组,可能实际上也规定了两个不同的时标.大统一理论时标和引力时标之间在宇宙演化历史不同时期的差异也许能为最近的一些宇宙学观测提供合理的解释.文章将表明,如果两者之间存在合适的差异,则视界问题可以得到自然的解决而暗能量概念的引入也变得没有必要.考察距离观察者不同远近的双星体系中由引力行为决定的转动周期和由大统一理论决定的某个衰变动力学过程特征时间,比如来自X射线双星体系的X射线辐射,比照两者在宇宙不同历史时期的差异,或能为我们的猜想提供观测证据.  相似文献   
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For further research on the gravity mechanism of the routing protocol in complex networks,we introduce the concept of routing awareness depth,which is represented by ρ.On this basis,we define the calculation formula of the gravity of the transmission route for the packet,and propose a routing strategy based on the gravitational field of the node and the routing awareness depth.In order to characterize the efficiency of the method,we introduce an order parameter,η,to measure the throughput of the network by the critical value of phase transition from free flow to congestion,and use the node betweenness centrality,B,to test the transmission efficiency of the network and congestion distribution.We simulate the network transmission performance under different values of the routing awareness depth,ρ.Simulation results show that if the value of the routing awareness depth ρ is too small,then the gravity of the route is composed of the attraction of very few nodes on the route,which cannot improve the capacity of the network effectively.If the value of the routing awareness depth ρ is greater than the network's average distance l,then the capacity of the network may be improved greatly and no longer change with the sustainable increment of routing awareness depth ρ,and the routing strategy performance enters into a constant state.Moreover,whatever the value of the routing awareness depth ρ,our algorithm always effectively balances the distribution of the betweenness centrality and realizes equal distribution of the network load.  相似文献   
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