A symmetric and conserved energy-momentum tensor for a scalar field in a
moving medium is derived using the Gordon metric. When applied to an
electromagnetic field, the method gives a similar result. This approach thus
points a way out of the old Abraham-Minkowski controversy about the correct
energy-momentum tensors for the electromagnetic field in a material medium. The
new tensor describes the properties of the field while the Abraham tensor
contains information about the field coupled to the medium.Comment: 5 pages, LaTeX, two references added with commentar
