Constitutive relation, 0 electrodynamics

In the presence of matter (electrons and protons), the inhomogeneous field equation (32) can be expanded as given in Eqs. (52)-(54) and interprets the inverse Faraday effect self-consistently as argued already. Constitutive relations such as Eq. (55) must be used as in U(l) electrodynamics. 

In this section, we formulate the Maxwell equations that govern the behavior of the electromagnetic fields. We present the fundamental laws of electromagnetism, derive the boundary conditions and describe the properties of isotropic, anisotropic and chiral media by constitutive relations. Our presentation follows the treatment of Kong [122] and Mishchenko et al. [169], Other excellent textbooks on classical electrodynamics and optics have been given by Stratton [215], Tsang et al. [228], Jackson [110], van de Hulst [105], Kerker [115], Bohren and Huffman [17], and Born and Wolf [19]. 

This definition is related to the difference between left- and right-handed photons because B(3) switches sign between left and right circularly polarized electromagnetic radiation. Therefore, H and B(3) constitute electromagnetic helicities of a knot, and there is also a link between B(3) and the Sachs theory [1], as shown in the review [6] by Evans, linking 0(3) electrodynamics and the Sachs theory. 

We will review here experimental tests of quantum electrodynamics (QED) and relativistic bound-state formalism in the positron-electron (e+,e ) system, positronium (Ps). Ps is an attractive atom for such tests because it is purely leptonic (i.e. without the complicating effects of nuclear structure as in normal atoms), and because the e and e+ are antiparticles, and thus the unique effects of annihilation (decay into photons) on the real and imaginary (related to decay) energy levels of Ps can be tested to high precision. In addition, positronium constitutes an equal-mass, two-body system in which recoil effects are very important. 

A system may contain energy when it possesses the ability to store it, as already stated. This ability takes the form of two constitutive properties, one for each subvariety of energy inductance for the inductive subvariety, and capacitance for the capacitive one. These names are borrowed from electrodynamics and generalized to all energy varieties. So, there is a translational mechanical inductance (inertial mass), a rotational mechanical inductance (inertia), a hydrodynamical capacitance (compressibility integrated over the volume), a thermal capacitance (which depends on the specific heat), and so on. In electrodynamics, inductance and capacitance feature components called inductor (or self-inductance) and capacitor, respectively. Electric inductance relates current to the quantity of induction (induction flux) and electric capacitance relates potential to charge. 

The association of an inductor with a capacitor allows the two snbvarieties of electrodynamical energy, inductive (electromagnetic) and capacitive (electric or electrostatic), to be stored in the same system. The two system constitutive properties, inductance and capacitance, are the supports for the storage of energy and they link the state variables according to the following relations ... 

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