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The Electromagnetic Field in Rotating CoordinatesA. GEORGIOUThe electromagnetic field equations in rotating coordinates obtained by various authors, are based on incorrect expressions for the divergence and curl operators and the electromagnetic spatial vectors. This is a serious error in this most important aspect o f electromagnetic theory. Maxwell's equations are shown to be valid in rotating Coordinates.The problem of the electromagnetic field equations in rotating coordinates has been discussed in the literature by a number of authors. In particular, Schiff [I], and Atwater [2] obtained field equations which are extremely complicated and distinctly unlike Maxwell's equations. This i s a serious problem in electromagnetic theory, because it challenges the validity of Maxwell's equations in rotating Coordinates. We shall show that these treatments are faulty because they are based on incorrect expressions forthe electromagnetic 3-vectors and the 3-current and charge densities, as well as the divergence and curl operators.Shiozawa, (see remarks by T. Shiozawa in [2]), seems to have obtained Maxwell-like equations in rotating coordinates, but his treatment i s also based on incorrect expressions for the various quantities. The main source of error in all these treatments, is the failure to take account of the fact that the geometry of physical 3-space in rotating coordinates i s non-Euclidean.A treatment of Maxwell's equations in general coordinates was given by MQller [3]. We have also shown that these equations are valid in all coordinate systems in flat and curved spaces [4]. Here we shall deal specifically with rotating coordinates.We shall use theconvention in which Greek indices take thevalues 1,2,3,4for the spacetimecoordinates with x4 = t, Roman indices take the values 1,2, 3 for the space coordinates, the signature of the spacetime metric tensor g,, is +2, a comma denotes partial differentiation and we shall use M K S units. The electromagnetic field equations in vacuum electrodynamics expressed in tensor form arewhere F,. and Fp' = g""gU4Fmu are the covariant and contravariant electromagnetic tensors, i s the electric 4-current, po is the magnetic permeability of the vacuum, and g = lgpv1. We shall assume
\-IWe note that the indices of spatial vectors are lowered and raised using the tensors y,, and y" respectively, and that the forms (covariant or ...