ShangGang Group

New Haven, CT, United States

ShangGang Group

New Haven, CT, United States
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Wang C.,ShangGang Group
Optik | Year: 2017

A mathematical conjecture is successfully identified, which is used for relativistic analysis of dielectric Einstein-box thought experiment in a Letter (Ramos, Rubilar, and Obukhov, Phys. Lett. A 375, 1703 (2011)), where the authors conjecture (without any citations) that, the symmetry and divergence-less property of a Lorentz 4-tensor is a sufficient condition for the time-column space integrals to constitute a Lorentz 4-vector. This mathematical conjecture has been thought to be “a mathematical fact the validity of which was shown well” in textbooks. However in this paper, we indicate that this conjecture has never been proved mathematically. By enumerating a counterexample, we find that this mathematical conjecture is flawed, and it is not persuasive to use a flawed mathematical conjecture as a starting point to resolve Abraham-Minkowski controversy over light momentum in a dielectric medium. We also indicate that this flawed mathematical conjecture is actually a widely-accepted conjecture in the dynamics of relativity in textbooks for many decades. To eliminate a misunderstanding of this flawed conjecture in the community, we provide a detailed elucidation of why Møller's mathematical statement, also called “Møller's version of von Laue's theorem”, only defines a trivial zero 4-vector for an electromagnetic stress-energy Lorentz 4-tensor. © 2017 Elsevier GmbH


Wang C.,ShangGang Group
Optik | Year: 2016

A conventional general electromagnetic force definition has been widely used to analyze radiation forces in dielectric media in published research works. However in this paper, we would like to indicate that this conventional force definition is flawed. © 2015 Elsevier GmbH. All rights reserved.


Wang C.,ShangGang Group
Canadian Journal of Physics | Year: 2015

A self-consistent theory is developed based on the principle of relativity for a plane wave in a moving non-dispersive, lossless, non-conducting, isotropic, uniform medium. A light-momentum criterion is set up for the first time, which states that the momentum of light in a medium is parallel to the wave vector in all inertial frames of reference. By rigorous analysis, novel basic properties of the plane wave are exposed: (i) Poynting vector does not necessarily represent the electromagnetic (EM) power flow when a medium moves; (ii) Minkowski light momentum and energy constitute a Lorentz four-vector in a form of single EM-field cell or single photon, and Planck constant is a Lorentz invariant; (iii) there is no momentum transfer taking place between the plane wave and the uniform medium, and the EM momentum conservation equation cannot be uniquely determined without resorting to the principle of relativity; and (iv) when the medium moves opposite to the wave vector at a faster-than-dielectric light speed, negative frequency and negative EM energy density occur, with the plane wave becoming left-handed. Finally, a new physics of so-called "intrinsic Lorentz violation" is presented as well. © 2015 Published by NRC Research Press.


Wang C.,ShangGang Group
Canadian Journal of Physics | Year: 2015

von Laue's theorem, as well as its generalized form, is strictly proved in detail for its sufficient and necessary condition (SNC). This SNC version of Laue's theorem is used to analyze the infinitely extended electrostatic field produced by a charged metal sphere in free space, and the static field confined in a finite region of space. It is shown in general that the total (Abraham=Minkowski) electromagnetic momentum and energy for the electrostatic field cannot constitute a Lorentz four-vector. A derivative von Laue's theorem, which provides a criterion for a Lorentz invariant, is also presented. © 2015 Published by NRC Research Press.


Poynting vector as electromagnetic power flow has prevailed over one hundred years in the community. However in this paper, it is shown from Maxwell equations that the Poynting vector may not represent the electromagnetic power flow for a plane wave in an anisotropic medium; this important conclusion revises the conventional understanding of Poynting vector. It is also shown that this conclusion is clearly supported by Fermat's principle and special theory of relativity. © 2015 Elsevier GmbH.


Wang C.,ShangGang Group
Progress In Electromagnetics Research B | Year: 2010

Numerical results are presented for single-mode guidance, which is based on photonic band gap (PBG) effect, in one-dimensional planar all-dielectric light-guiding systems. In such systems there may be two kinds of light-speed point (the intersection of a mode-dispersion curve and the light line of guiding region ambient medium): One is the intrinsic light-speed point that is independent of the guiding region width, and the other is the movable light-speed point that varies with the guiding region width. It is found that the intrinsic lightspeed point plays an important role to form the single-mode regime by destroying the coexistence of the lowest guided TM and TE modes that are born with a degeneration point. A mode-lost phenomenon is exposed and this phenomenon suggests a way of how to identify PBG guided fundamental modes. Quasi-cutoff-free index-guided modes in the PBG guiding structures are examined, which appear when the higher-index layers are adjacent to the guiding region and the guiding region width is small. The transverse resonance condition is derived in the Maxwell optics frame, and it is shown that there is a significant revision to the traditional one in the ray optics model. A sufficient and necessary condition for intrinsic light-speed points is given, which provides strong support to the numerical results.


It is shown without making use of Lorentz transformation that there exists a phenomenon of relativistic zero-frequency shift in Doppler effect for a plane wave in free space, observed in two inertial frames of relative motion, and the zero shift takes place at a maximum aberration of light. When it is applied to analysis of a moving point light source, two unconventional physical implications result: (1) a light source, when it is approaching (moving closer to) the observer, may cause a red shift; (2) a zero-frequency-shift observation does not necessarily mean that the light source is not moving closer, and in contrast, the light source may be moving closer to the observer at a high speed. This fundamental result of special relativity may provide an alternative way to experimentally examine the principle of relativity, and might have a significant application in astrophysics. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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