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Electromagnetic properties of a simple polarisable medium may beparameterised in terms of a constitutive tensor whose properties can inprinciple be determined by experiments in non-inertial (accelerating) framesand in the presence of weak but variable gravitational fields. Afterestablishing some geometric notation, discussion is given to basic concepts ofstress, energy and momentum in the vacuum where the useful notion of a driveform is introduced in order to associate the conservation of currents involvingthe flux of energy, momentum and angular momentum with spacetime isometries.The definition of the stress-energy-momentum tensor is discussed withparticular reference to its symmetry based on its role as a source ofrelativistic gravitation. General constitutive properties of material continuaare formulated in terms of spacetime tensors including those that describemagneto-electric phenomena in moving media. This leads to a formulation of aself-adjoint constitutive tensor describing, in general, inhomogeneous,anisotropic, magneto-electric bulk matter in arbitrary motion. The question ofan invariant characterisation of intrinsically magneto-electric media isexplored. An action principle is established to generate the phenomenologicalMaxwell system and the use of variational derivatives to calculatestress-energy-momentum tensors is discussed in some detail. The relation ofthis result to tensors proposed by Abraham and others is discussed in theconcluding section where the relevance of the whole approach to experiments onmatter in non-inertial environments with variable gravitational andelectromagnetic fields is stressed.Comment: Typos correcte

New perspectives on the relevance of gravitation for the covariant description of electromagnetically polarizable media