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1.
In Newton's mechanics, Maxwell's electromagnetism, Einstein's relativistic mechanics, quantum mechanics, and Kantor's information mechanics (IM), the speed of light in vacuumc has been treated as independent of wavelength. However, in IM, the transport of information by means of an electromagnetic signal appears to offer a perspective for reconsidering photon information transport speed, extending the concept of (rest) mass to treat the photon as having a mass of 1 bit.  相似文献   

2.
We develop a general unified theory of classical mechanics and classical electromagnetism in a gravitational field on Friedman-Schöuten space-time (FSS). In this formalism (i) local equations of a charged fluid in an electromagnetic field are the same as in classical mechanics, (ii) local equations for a moving charged fluid are the same as in electromagnetism, (iii) the path of a charged particle under gravity and electromagnetism is a geodesic of the four-dimensional FSS, and (iv) the strong equivalence principle and a nonzero torsion coexist without conflict.  相似文献   

3.
Charge, like mass in Newtonian mechanics, is an irreducible element of electromagnetic theory that must be introduced ab initio. Its origin is not properly a part of the theory. Fields are then defined in terms of forces on either masses—in the case of Newtonian mechanics, or charges in the case of electromagnetism. General Relativity changed our way of thinking about the gravitational field by replacing the concept of a force field with the curvature of space-time. Mass, however, remained an irreducible element. It is shown here that the Reissner-Nordström solution to the Einstein field equations tells us that charge, like mass, has a unique space-time signature.  相似文献   

4.
The group theoretical structure of an infinite dimensional Hamiltonian formulation of continuum mechanics is studied using as an example the Maxwell-Vlasov system. In contrast to earlier works, electromagnetism and charged matter are coupled via Poisson brackets without using the vector potential. The charged matter is described on the group of canonical transformations on R6 and we show that its evolution arises from a symplectic structure, modified by the magnetic field. The configurations of the electromagnetic field must be constrained by the physical requirement of the Gauss law. With the energy-functional taken as a Hamiltonian this leads - even for relativistic particles - to the well-known equations of motion.  相似文献   

5.
In this work we employ a field theoretical approach to explain the nature of the non-conserved spin current in spintronics. In particular, we consider the usual U(1) gauge theory for the electromagnetism at classical level in order to obtain the broken continuity equation involving the spin current and spin-transfer torque. Inspired by the recent work of A. Vernes, B. L. Gyorffy and P. Weinberger where they obtain such an equation in terms of relativistic quantum mechanics, we formalize their result in terms of the well known currents of field theory such as the Bargmann–Wigner current and the chiral current. Thus, an interpretation of spintronics is provided in terms of Noether currents (conserved or not) and symmetries of the electromagnetism. In fact, the main result of the present work is that the non-conservation of the spin current is associated with the gauge invariance of physical observables where the breaking term is proportional to the chiral current. Moreover, we generalize their result by including the electromagnetic field as a dynamical field instead of an external one.  相似文献   

6.
We present some interesting connections between PT symmetry and conformal symmetry. We use them to develop a metricated theory of electromagnetism in which the electromagnetic field is present in the geometric connection. However, unlike Weyl who first advanced this possibility, we do not take the connection to be real but to instead be PT symmetric, with it being \(iA_{\mu }\) rather than \(A_{\mu }\) itself that then appears in the connection. With this modification the standard minimal coupling of electromagnetism to fermions is obtained. Through the use of torsion we obtain a metricated theory of electromagnetism that treats its electric and magnetic sectors symmetrically, with a conformal invariant theory of gravity being found to emerge. An extension to the non-Abelian case is provided.  相似文献   

7.
It is shown that not all linear electromagnetic constitutive laws will define almost‐complex structures on the bundle of 2‐forms on the spacetime manifold when composed with the Poincaré duality isomorphism, but only a restricted class of them that includes linear spatially isotropic and some bi‐isotropic constitutive laws. Although this result does not trivialize the formulation of the basic equations of pre‐metric electromagnetism, it does affect their reduction to metric electromagnetism by its effect on the types of media that are reducible, and possibly its effect on the way that such media support the propagation of electromagnetic waves.  相似文献   

8.
Journal of High Energy Physics - We reformulate classical electromagnetism as the statistical mechanics of lines of electric flux with dynamics described by the string action in four dimensions....  相似文献   

9.
In the first of these two studies it is argued that the discrepancy between the predicted and actual outcome of the Michelson-Morley experiment is due to the use of Newton's velocity addition theorem in conjunction with an electromagnetic theory of light. The ether hypothesis is not directly affected at all. The second study is a case study of the removal of a clash in physics generated from the outcome of an experiment. The clash due to the Michelson-Morley experiment gave rise to a program of revision. In the process of implementation of this program Newtonian mechanics was remolded. It is argued that the Riemannian space-time in Einstein's general theory of relativity may be regarded as a successor of the classical ether.  相似文献   

10.
Some concepts of real and complex projective geometry are applied to the fundamental physical notions that relate to Minkowski space and the Lorentz group. In particular, it is shown that the transition from an infinite speed of propagation for light waves to a finite one entails the replacement of a hyperplane at infinity with a light cone and the replacement of an affine hyperplane – or rest space – with a proper time hyperboloid. The transition from the metric theory of electromagnetism to the pre‐metric theory is discussed in the context of complex projective geometry, and ultimately, it is proposed that the geometrical issues are more general than electromagnetism, namely, they pertain to the transition from point mechanics to wave mechanics.  相似文献   

11.
本文将“物理类比法”引入大学物理电磁学部分的教学,将恒定流速场与静电场和静磁场在特征量、场的分布及其描述等方面进行了类比,使学生对电磁场有一个较清晰和全面的认识,对电磁学的理论有一个较深刻的理解和掌握,收到了较理想的教学效果.  相似文献   

12.
The reconcilability of gravitational with electromagnetic clocks suggests that a rigorous analysis of time will provide understanding of the unity of gravity and electromagnetism. Time is found to be fundamentally a property of elementary particles, only derivatively a property of clocks. A declaration is made: that the flow of an elementary particle's timeis the change of its radius, that time is therefore illusory. The de Sitter expanding universe is derived from this principle by treating elementary particles as spheres in Euclidean space. The hyperspheres of de Sitter space call up a five-dimensional metric manifold whose geometry models gravity, electromagnetism, and other phenomena tied to the structure of matter; neutrinos are provided for. Distance in this manifold is related to a secondary time, not correlated to primary time, but just as illusory. A particle's inertial rest mass is the relative rate of its two proper times; mass and charge are jointly, not individually, conserved.  相似文献   

13.
力学、热力学及电磁波导中的正则变换和辛描述   总被引:1,自引:0,他引:1       下载免费PDF全文
杨红卫  钟万勰  侯碧辉 《物理学报》2010,59(7):4437-4441
从正则变换入手,讨论经典力学中正则变换的辛描述,得到了正则变换的条件,给出了热力学系统满足正则变换条件的证明,同时给出了在辛体系下电磁波导的正则变换的物理意义.通过正则变换给出在辛体系下力学、热力学、电磁学公式的相似性,在统一理论方面做出有益探讨.  相似文献   

14.
I consider the direct product algebra formed from two isomorphic Clifford algebras. More specifically, for an element x in each of the two component algebras I consider elements in the direct product space with the form x x. I show how this construction can be used to model the algebraic structure of particular vector spaces with metric, to describe the relationship between wavefunction and observable in examples from quantum mechanics, and to express the relationship between the electromagnetic field tensor and the stress-energy tensor in electromagnetism. To enable this analysis I introduce a particular decomposition of the direct product algebra.  相似文献   

15.
We study noncommutative Chern-Simons mechanics and noncommutative Hall effect by Dirac theory in this paper. The magnetic field is introduced by means of minimal coupling. We show that the constraint set will enlarge when a dimensionless parameter takes zero value. In order to illustrate our idea, we study two specific models. One is noncommutative Chern-Simons mechanics which describes a charged particle on a noncommutative plane interacting with a perpendicular uniform magnetic field. The other is a charged particle on a noncommutative plane with a background uniform electromagnetic field. We show that when the dimensionless parameter tends to zero, the particle will live in a lower dimensional space in both models. Noncommutative Chern-Simons mechanics will reduce to a harmonic oscillator and the classical equations of motion of a charged particle in the background of a uniform electromagnetic field are governed by classical Hall law when the dimensionless parameter tends to zero.  相似文献   

16.
A new class of gravitational effects, in the quantum interference of charged particles, are studied in electron interferometry and superconducting Josephson interferometry. These include phase shifts due to the gravitationally induced Schiff-Barnhill field, rotationally induced London moment, and the modification of the Aharonov-Bohm type of phase shifts, due to the general relativistic coupling of the electromagnetic field to the gravitational field. These effects are interesting, even from a purely theoretical point of view, because they involve an elegant interplay between gravitation, electromagnetism, and quantum mechanics. But new predictions are also made which, if confirmed, would provide the first observation of relativistic gravitational effects, involving the electric charge, at the quantum mechanical level. The possibility of using these effects to detect gravitational waves is also discussed.This essay received the first award from the Gravity Research Foundation for the year 1983-Ed.  相似文献   

17.
18.
张剑 《大学物理》2004,23(7):57-59
指出量子力学也存在类似于电磁波的Goos-Hanchen效应.用二维波包在二维势阶的散射模型分析了Coos-Hanchen效应的内在原因.  相似文献   

19.
A geometrical unified field theory of electromagnetism and gravitation is developed in a Weyl space-time. The integrability conditions of the field equations cast the laws of classical perfect fluids under electromagnetic interactions. The purely gravitational limit of the theory is Einstein's General Relativity and the purely electromagnetic case coincides with the predictions of Maxwell's theory.  相似文献   

20.
Weyl proposed a geometry that differed from Riemannian geometry, which underlies general relativity, in that it contained a vector that could be interpreted as describing the electromagnetic field. Dirac modified this geometry to remove certain difficulties and based it on a variational principle which gave satisfactory field equations for gravitation and electromagnetism. However, by changing the value of a parameter appearing in his variational principle one gets, instead of electromagnetism, a field of massive particles of spin 1, which can be assumed to interact with ordinary matter only through gravitation. It is suggested that these bosons, called weylons, provide most of the dark matter in the universe.  相似文献   

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