Its trace is the divergence of the dilatation current, and thus zero in a conformal theory. In Yang-Mills theory it corresponds to an interpolating operator for spin 2 glueballs. For an ideal fluid, knowing it is equivalent to knowing the pressure and density, and it is diagonal in a comoving frame. The Noether procedure finds it as a set of conserved currents associated to translation invariance, but this may not produce a symmetric answer. The usual symmetric definition is a variation of the nongravitational part of t
Its trace is the divergence of the dilatation current, and thus zero in a conformal theory. In Yang-Mills theory it corresponds to an interpolating operator for spin 2 glueballs. For an ideal fluid, knowing it is equivalent to knowing the pressure and density, and it is diagonal in a comoving frame. The Noether procedure finds it as a set of conserved currents associated to translation invariance, but this may not produce a symmetric answer. The usual symmetric definition is a variation of the nongravitational part of the action with respect to the metric. FTP, what is this quantity that the Einstein equations relate to the curvature of space?
Its trace is the divergence of the dilatation current, and thus zero in a conformal theory.
stress-energy tensor (accept energy-momentum tensor or stress-energy-momentum tensor)