We present new one loop calculations that confirm the theorems of Joglekar and Lee on the renormalization of composite operators. We do this by considering physical matrix elements with the operators inserted at non-zero momentum. The resulting IR singularities are regulated dimensionally. We show that the physical matrix element of the BRST exact gauge variant operator which appears in the ene...

By extending Ashtekar and Romano’s definition of spacelike infinity to the timelike direction, a new definition of asymptotic flatness at timelike infinity for an isolated system with a source is proposed. The treatment provides unit spacelike 3-hyperboloid timelike infinity and avoids the introduction of the troublesome differentiability conditions which were necessary in the previous works on...

The Bel tensor is divergence-free in some important cases leading to the existence of conserved currents associated to Killing vectors analogously to those of the energy-momentum tensor. When the divergence of the Bel tensor does not vanish one can study the interchange of some quantities between the gravitational and other fields obtaining mixed total conserved currents. Nevertheless, the Bel ...

We study the effective energy-momentum tensor (EMT) for cosmological perturbations and formulate the gravitational back-reaction problem in a gauge invariant manner. We analyze the explicit expressions for the EMT in the cases of scalar metric fluctuations and of gravitational waves and derive the resulting equations of state. The formalism is applied to investigate the back-reaction effects in...

We calculate the thermal Euclidean correlators and the spectral functions of the energymomentum tensor for pure gauge theories, including at non-zero spatial momentum, at leading order in perturbation theory. Our goal is to improve the extraction of transport properties from Euclidean correlators that are computable in lattice QCD. Based on our results and the predictions of hydrodynamics for t...

Collective flow has been observed in heavy ion collisions, with a large anisotropic component, and ideal hydrodynamic calculations had significant successful in describing the distribution of produced particles at the RHIC experiments. In order to account for this near ideal fluid behavior, the shear and bulk viscosity of the quark gluon plasma (QGP) must be computed from first principles in a ...

Within the Lagrange formalism we show that the gauge invariant total energy-momentum tensor for gravitational interactions is zero. If the equations of motion are satisfied the energy tensor is conserved.

In recent papers [1-3], we have discussed matter symmetries of non-static spherically symmetric spacetimes, static plane symmetric spacetimes and cylindrically symmetric static spacetimes. These have been classified for both cases when the energy-momentum tensor is non-degenerate and also when it is degenerate. Here we add up some consequences and the missing references about the Ricci tensor. ...