力学相对性原理

本文仅从教学意义上，给出论述力学相对性原 理的一个方案．指出，对牛顿定律而言．应先假设作 用力在两惯性系中有相同的值，再论证定律在不同惯 性系中同形．     

展示相对性原理和电磁场相对性的一个佳例

以条形磁铁与导体圆环相对运动为例,依据导体圆环产生感应电流这一事实,首先讨论了条形磁铁参考系和导体圆环参考系下电场和磁场的不同.并在条形磁铁参考系下,从产生动生电动势的物理本质洛伦兹力出发,导出了法拉第电磁感应定律.然后,在导体圆环参考系下,由相对性原理直接给出了感生电场性质的数学表述,并深入讨论了电场和磁场的联系.最后,给出了爱因斯坦和费曼对该问题的不同思考并进行了简单分析.     

力学相对性原理与机械能

本文指出，只包括内势能的机械能定理和机械 能守恒定律满足力学相对性原理．但是，包括稳定外 势能的机械能定理和机械能守恒定律是不满足力学相对性原理的．机械能守恒定律是否满足力学相对性原理，取决于对势能的处理方法，与力学系统受力状态和机械能守恒条件的表述方式无关     

简谈功、动能的相对性

功、动能具有相对性，这点常常被同学们忽视，也是同学们难于理解、感到困惑的地方，下面我就谈谈功和动能的相对性，以帮助同学们更好的理解功和动能。     

机械能守恒定律和相对性原理

详细阐述了机械能守恒定律成立的条件及该定律服从力学相地性原理所需满足的条件,回答了《河北师范学院学报（自然科学版）》在１９９７年第２期上赵佩章等同志对本刊多年来氯表的有关文章的批评     

机械能守恒定律服从力学相对性原理

阐述了机械能守恒定律服从力学相对性原理。     

关于力学相对性原理和机械能守恒定律的讨论也谈机械能守恒定律和相对性原理

指出机械能守恒定律是服从相对性原理的.     

关于力学相对性原理与机械能守恒的来稿综述

关于力学相对性原理与机械能守恒的来稿综述本刊编辑部本刊１９９１年第１１期刊登管靖“力学相对性原理与机械能”一文后，收到河北廊坊管道职工学院白静江、湖北宜昌师专吴恒钦等同志５篇与此有关的文章。由于本刊发排周期较长，不可能组织紧凑的不同观点的讨论，所以只...     

"机械能守恒定律是否遵从相对性原理"辨

从两个层次上的相对性原理出发,对“机械能守恒定律是否遵从相对性原理”进行了剖析;并对究竟把什么称作机械能守恒定律更为合理,提出了一些看法。     

The Inertial Transformations and the Relativity Principle

Our recently proposed inertial transformations of the space and time variables based on absolute simultaneity imply the existence of a single isotropic inertial reference system (“privileged system”). We show, however, that aresynchronization of clocks in all inertial systems is possible leading to a different, arbitrarily chosen,isotropic “privileged” system. Such a resynchronization does not modify any one of the empirical consequences of the theory,which is thus compatible with a formulation of the relativity principle weaker than adopted in Einstein’s theory of special relativity.     

On the Principle of Relativity

In a recent article [1] M.A. Oliver argues there is a conflict between Einstein's Special Theory of Relativity (STR) and Cosmology. In ascertaining this conflict (see below), Oliver finds allies in Bergmann [2] and Bondi [3]. To resolve this conflict, he proposes to restore the classical (mechanical) concepts of space and time [1, p.666] and an absolute rest-frame. I shall devote a few words (1) to the Principle of Relativity and (2) to the notion of cosmic time in cosmology; this enables me (3) to argue that the alleged conflict between STR and Cosmology is based on a misunderstanding of the Principle of Relativity. (4) Finally I take a critical look at Oliver's allies.     

The Maximum Tension Principle in General Relativity

I suggest that classical General Relativity in four spacetime dimensions incorporates a Principal of Maximal Tension and give arguments to show that the value of the maximal tension is . The relation of this principle to other, possibly deeper, maximal principles is discussed, in particular the relation to the tension in string theory. In that case it leads to a purely classical relation between G and the classical string coupling constant and the velocity of light c which does not involve Planck's constant.     

On the Foundation of the Principle of Relativity

The relation of the special and the general principle of relativity to the principle of covariance, the principle of equivalence and Mach's principle, is discussed. In particular, the connection between Lorentz covariance and the special principle of relativity is illustrated by giving Lorentz covariant formulations of laws that violate the special principle of relativity: Ohm's law and what we call Aristotle's first and second laws. An Aristotelian universe in which all motion is relative to absolute space is considered. The first law: a free particle is at rest. The second law: force is proportional to velocity. Ohm's law: the current density is proportional to the electrical field strength. Neither of these laws fulfills the principle of relativity. The examples illustrate, in the context of Lorentz covariance and special relativity, Kretschmann's critique of founding Einstein's general principle of relativity on the principle of general covariance. A modification of the principle of covariance is suggested, which may serve as a restricted criterium for a physical law to satisfy Einstein's general principle of relativity. Other objections that have been raised to the validity of Einstein's general principle of relativity are based upon the preferred state of inertial frames in the general, as well as in the special theory, the existence of tidal effects in true gravitational fields, doubts as to the validity of Mach's principle, whether electromagnetic phenomena obey the principle, and, finally, the anisotropy of the cosmic background radiation. These objections are reviewed and discussed.     

The String Uncertainty Relations Follow from the New Relativity Principle

Stringy corrections to the ordinary Heisenberg uncertainty relations have been known for some time. However, a proper understanding of the underlying new physical principle modifying the ordinary Heisenberg uncertainty relations has not yet emerged. The author has recently proposed a new scale relativity theory as a physical foundation of string and M theories. In this work the stringy uncertainty relations, and corrections thereof, are rigorously derived from this new relativity principle without any ad-hoc assumptions. The precise connection between the Regge trajectory behavior of the string spectrum and the area quantization is also established.     

The Principle of Covariance and the Hamiltonian Formulation of General Relativity

The implications of the general covariance principle for the establishment of a Hamiltonian variational formulation of classical General Relativity are addressed. The analysis is performed in the framework of the Einstein-Hilbert variational theory. Preliminarily, customary Lagrangian variational principles are reviewed, pointing out the existence of a novel variational formulation in which the class of variations remains unconstrained. As a second step, the conditions of validity of the non-manifestly covariant ADM variational theory are questioned. The main result concerns the proof of its intrinsic non-Hamiltonian character and the failure of this approach in providing a symplectic structure of space-time. In contrast, it is demonstrated that a solution reconciling the physical requirements of covariance and manifest covariance of variational theory with the existence of a classical Hamiltonian structure for the gravitational field can be reached in the framework of synchronous variational principles. Both path-integral and volume-integral realizations of the Hamilton variational principle are explicitly determined and the corresponding physical interpretations are pointed out.     

The Principle of Equivalence,electrodynamics and General Relativity

It is shown that the customary covariant formulation of electrodynamics in General Relativity is incompatible with the Einstein Principle of Equivalence. This is demonstrated for the case of a resistanceless current-carrying wire in a static spherically symmetric gravitational field—where the Einstein Principle of Equivalence implies the existence, in the vicinity of the wire, of a non-zero component of the electric field parallel to the wire, whereas the covariant form of Maxwell's equations does not. An experiment, involving a superconducting current-carrying wire segment placed in the Earth's gravitational field, is suggested. Whether or not a component of electric field parallel to the wire, at a point in the wire's vicinity, would be detected would resolve the issue.     

Gauge Formalism for General Relativity and Fermionic Matter

A new formulation for General Relativity is developed; it is a canonical, global and geometrically well posed formalism in which gravity is described using only variables related to spin structures. It does not require any background metric fixing and it applies to quite general manifolds, i.e. it does not need particular symmetries requirement or global frames. A global Lagrangian framework for Dirac spinors is also provided; conserved quantities and superpotentials are given. The interaction between gravity and spinors is described in a minimal coupling fashion with respect to the new variables and the Hilbert stress tensor of spinor fields is computed, providing the gravitational field generated by spinors. Finally differences and analogies between this formalism and gauge theories are discussed.