Electrodynamic phenomena in a dark fluid flow

Abstract

We consider dark fluid as a medium, which acts indirectly on cosmic electromagnetic fields of all types. We develop mathematical models for dark analogs of pyromagnetic, piezomagnetic and dynamo-optical effects, magnetostriction and optical activity in minimal and nonminimal versions.Keywords: Dark fluid; axion electrodynamics; MG14 Proceedings. Dark Fluid as an Electromagnetically Active MediumDark fluid composed of a dark energy and dark matter has a status of a key constitutive element of modern cosmological models (see, e.g., 2− 6 for review, references and terminology). Both the dark energy and dark matter are assumed to consist of electrically neutral particles and thus the dark fluid does not interact with an electromagnetic field directly.Electrodynamic systems of the Universe are incorporated into the baryonic matter (its modern contribution into the Universe energy balance is estimated as 5%). On the one hand, these electrodynamic systems form the basic channel of the information about the Universe structure; on the other hand, they are subordinate elements from the point of view of the Universe energy distribution. In this context each cosmic electrodynamic system can be considered as a marker, which signalizes about the variations in the state of the dark fluid, the energetic reservoir, into which this marker is immersed.We are interested to answer the question: what mechanisms might be responsible for a (possible) transmission of information about the dark fluid state to the electrodynamic systems. These mechanisms could help to reconstruct features of the dark fluid evolution, e.g., by tracking down specific fine details of the spectrum of observed electromagnetic waves, of their phase and group velocities.Classification, review and discussion about schemes of mathematical description of these marker-effects are the main purposes of the presented talk. Let us focus, first, on the list of models, which describe the indirect influence of the dark fluid on the electromagnetic fields of various structure. The key idea is that the dark fluid can be considered as a specific cosmic medium in which the electromagnetic fields evolve. In this sense we can attract the attention to effects well-known and welltested in the electrodynamics of moving polarizable/magnetizable continuous media in classical (relativistic) theory. For this purpose, in addition to the Maxwell tensor F ik , which describes the electromagnetic field strength, one uses the excitation