Showing papers on "Four-tensor published in 1976"
TL;DR: The requirement of the conformal covariance of the theory in the limit of vanishing masses leads to "improving" terms in energy-momentum tensors in this paper.
Abstract: The requirement of the conformal covariance of the theory in the limit of vanishing masses leads to “improving” terms in energy-momentum tensor. Some consequences of the fact are briefly summarized.
102 citations
TL;DR: In this article, the authors constructed non-trivial conserved charges in the massive Thirring model with dimension and tensor structure of the associated densities higher than those of the energy-momentum tensor.
15 citations
TL;DR: In this article, a proper identification of the total stress (or momentum flow) tensor for a closed system consisting of an arbitrary dielectric crystal in interaction with the electromagnetic field is found.
Abstract: From arguments based on momentum conservation, the stress boundary condition, the allowed functional dependence of a stress tensor, the gauge invariance, and the vacuum form of the Maxwell stress tensor, a proper identification of the total stress (or momentum flow) tensor for a closed system consisting of an arbitrary dielectric crystal in interaction with the electromagnetic field is found. This tensor is shown to be asymmetric even though the system conserves angular momentum. Jump conditions on the total stress tensor are found both for surfaces fixed in the spatial or laboratory coordinate system, and for surfaces fixed in the material or body coordinate system, and thus moving and deforming with respect to the laboratory coordinate system. The ideas developed are also applied to the flow of energy and the flow of angular momentum.
12 citations
TL;DR: The mathematical meaning of the law of conservation of energy-momentum is examined in this article, and a distinction is made between the intrinsic properties of the metric tensor (i.e., those properties that are independent of the coordinate system) and the non-intrinsic properties of this tensor, i.e. properties that depend upon the coordinate systems.
Abstract: The mathematical meaning of the law of conservation of energy-momentum is examined A distinction is made between the intrinsic properties of the metric tensor (ie, those properties that are independent of the coordinate system), and the nonintrinsic properties of this tensor (ie, those properties that depend upon the coordinate system) The covariance of the energy-momentum law is used to demonstrate that if one is given (a) any analytic contravariant energy-momentum tensor density in a given coordinate systemx and (b) an analytic specification of the intrinsic properties of the metric tensor, no matter what these properties may be, one can always choose the nonintrinsic properties of the metric tensor in such manner as to satisfy the law of conservation of energy-momentum in the coordinate systemx and thereby in every coordinate system This result is proved only in the case where the contravariant components of the energy-momentum tensor density are given Neither the covariant, nor the mixed energy-momentum tensor densities are considered Other theorems similar to that described above are also derived Many of the results obtained are nontrivial even when space-time is flat
3 citations