Helicity plays an important role in spectacular geophysical phenomena such as hurricanes or the generation of terrestrial magnetic field. The present investigation shows how helicity can be created a statistically homogeneous but anisotropic flow, driven by buoyancy. If flow is close enough to two-dimensional limit, spontaneous symmetry breaking leads mean helicity. In particular, we explain th...

We present a framework to systematically study the duality properties of scatterers. The duality properties of a scatterer are related to the polarization change that a particle excerpts on a light beam. Our formalism can be applied to any geometry and material, but we develop it in the context of spherical scatterers. Due to their symmetries, we can formulate the problem semi-analytically usin...

Symmetry principles play an important role with respect to the laws of nature. To put into a symmetrical shape the equations, coupling together the electric and magnetic fields, Maxwell added an electric displacement current. Such an additive, introduced for reasons of symmetry, resulted in appearing a unified-field structure: the electromagnetic field. The electric displacement current in Maxw...

The mathematics and physics of each the three aspects magnetic field evolution—topology, energy, helicity—are remarkably simple clear. When resistivity η is small compared to an imposed evolution, a/v, timescale, which means Rm≡μ0va/η≫1, field-line chaos dominates evolution topology in three-dimensional systems. Chaos has no direct role dissipation energy. A large current density, jη≡vB/η, requ...

Helicity preserving nanostructures and metasurfaces have been proposed as candidates to enhance spectroscopic features of chiral molecules. With this in mind, we show that losses the constituent materials impede conservation helicity systems such core–shells or inorganic spheres.