Dark matter description by non-conventional energy-momentum tensors

OSVALDO M. MORESCHI; EZEQUIEL BOERO; EMANUEL GALLO; FEDERICO GESER

AIP CONFERENCE PROCEEDINGS

AIP

Año: 2015 vol. 1647 p. 35 - 43

0094-243X

Most models used for the dark matter phenomenaassume a description in terms of a Newtonian framework.This in particular means that the energy momentum tensor has a      {dominant timelike $T_{00}$ component} and that the other       {spacelike components are negligible}.{What if the general relativistic framework were needed?}What could we be missing from a relativistic description?It is conceivable that other components of the energy momentum tensorare needed for an accurate description of dark matter phenomena.What are the {justifications} to consider other types of energy momentum tensors?There are several indications that suggest that something is missingin our picture of dark matter.Very often one recurs to models in which {averages} are madeeither for the distribution of matter, or the geometry.In trying to average geometric quantities it is not obvious whatquantities one should average: the metric? the connection? the curvature?In gravitational lensing studies spacelike components of the energy momentum tensor have normally been neglected.What are the {evidences} that we could probably need to considerother descriptions for dark matter phenomena?In a recent article by Serra-Dominguezcite{Serra:2011jh} they make a dynamical study of the galaxies in the Coma cluster and infer a content of matter.They compare their results with weak lens studies and the graph showsa notorious discrepancy (grey and black lines in Fig. ef{fig:serra-dominguez}).We review here some of this problems and present a new kind of energy momentumtensors that have non-trivial spacelike components andare suitable for the description of dark matter.