  In this paper we adopt a global and non-entropic approach to the problem of
the arrow of time, according to which the arrow of time is an intrinsic
geometrical property of spacetime. Our main aim is to show the double role
played by the energy-momentum tensor in the context of our approach. On the one
hand, the energy-momentum tensor is the intermediate step that permits to turn
the geometrical time-asymmetry of the universe into a local arrow of time
manifested as a time-asymmetric energy flow. On the other hand, the
energy-momentum tensor supplies the basis for deducing the time-asymmetry of
quantum field theory, posed as an axiom in this theory.
