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Chyla W.T.,Applied Science Enterprise
European Physical Journal Plus

If a luminous source moves with respect to the medium in which it is embedded, the kinematic shift of spectral lines depends both on the relative velocity and on the (relativistic) index of refraction of the medium. This effect is frequency-dependent, which makes it distinguishable from the cosmological redshift, the gravitational redshift and the regular Doppler shift in vacuum, which are all achromatic. The refraction-dependent shift of spectral lines is considered in more detail in the case of Ia supernovae, where the thermally generated electron-positron plasma ball, which expands with relativistic speeds, constitutes the refractive medium; it turns out that the discussed effect is relatively small at the UV and visible frequencies, but it can be significantly larger at longer wavelengths (the IR band). Other examples are given in optics and in other situations, where the refraction-dependent kinematic shift of frequency can be of significance. © 2015, The Author(s). Source

The classical, electrodynamic definition of the ampere is incoherent with quantum electrodynamics. The problem, although insignificant at the macroscopic scale, manifests clearly at the nanostructure level, where the consistently quantum approach is necessary. In this paper, we consider the Casimir eect to quantify inconsistencies that could have resulted if electric metrology of microstructures and nanostructures (including graphene) had been based on classical electrodynamics and the current SI definition of the ampere. The issue is discussed in the context of the New SI program, where the base electric unit is to be redefined by fixing the numerical value of the elementary charge. The conclusion supports the case for a prompt redefinition of the base electric unit, which will make the electric metrology in general, and the electric metrology of nanostructures in particular, coherent with the international system of units. Source

Chyla W.T.,Applied Science Enterprise

The key optical parameter of a relativistic medium is the relativistic index of refraction, n, which can be expressed in terms of the refractive index of the medium at rest, no, and parameters of motion (speed and direction). The two quantities, n and no, are related by the Lorentz boost transformation. In this paper, I give the explicit expression for n, which is instrumental, e.g. in image formation due to combined gravitational and refractive lensing or in the frequency-sensitive phenomena that involve the group velocity of light in the moving medium. © 2012 Elsevier GmbH. All rights reserved. Source

Chyla W.T.,Applied Science Enterprise

This letter examines the structure of draft definitions of the New SI base units, which are posted on the BIPM website. It is argued that the new definitions of base units should be free from references to derived units and should not comprise conditional phrases; names of base units should be clearly distinguished from their symbols. To alleviate the identified problems, relevant modifications of the draft definitions are proposed. © 2012 BIPM & IOP Publishing Ltd. Source

Applied Science LLC | Date: 2012-01-05

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