On the electrodynamics of moving bodies at low velocities

We discuss the seminal article in which Le Bellac and Levy-Leblond have identified two Galilean limits of electromagnetism, and its modern implications. We use their results to point out some confusion in the literature and in the teaching of special relativity and electromagnetism. For instance, it is not widely recognized that there exist two well defined non-relativistic limits, so that researchers and teachers are likely to utilize an incoherent mixture of both. Recent works have shed a new light on the choice of gauge conditions in classical electromagnetism. We retrieve Le Bellac-Levy-Leblond's results by examining orders of magnitudes, and then with a Lorentz-like manifestly covariant approach to Galilean covariance based on a 5-dimensional Minkowski manifold. We emphasize the Riemann-Lorenz approach based on the vector and scalar potentials as opposed to the Heaviside-Hertz formulation in terms of electromagnetic fields. We discuss various applications and experiments, such as in magnetohydrodynamics and electrohydrodynamics, quantum mechanics, superconductivity, continuous media, etc. Much of the current technology where waves are not taken into account, is actually based on Galilean electromagnetism

Selective and “Veiled” Demarketing from the Perspective of Black Female Consumers

This study sheds light on the perspective of Black female consumers in regards to certain effects of marketing initiatives adopting the literature on demarketing as a framework. The context examined is their experience with the market of hair beauty and care. Media actions are analyzed along narrative interviews in order to understand the phenomenon. The findings reveal a structural dominant pattern which perpetuates the marginalized status of Black women’s natural traits. Emerging market initiatives point to movements concerning the visibility of such female consumers, who despite being eager to consume, have their demand discouraged. This suggests that they perceive a selective and veiled demarketing, as one of the results of marketing actions. The analysis invites for theoretical reflections on demarketing and veiled racism in Brazil

Electromagnetism and relativity: with particular reference to moving media and electromagnetic induction

The electromagnetic field of bodies in uniform rectilinear motion ; electromagnetic induction ; relativistic theory of second-order E.M.F.'s in moving circuits ; electromagnetic energy and momentum