Resistive Instabilities in Astrophysical Conditions: A Critical Discussion

Resistive instabilities have often been indicated as the possible cause of rapid release of energy in astrophysical situations. A correct assessment of the validity of this idea requires a detailed analysis of the theory of resistive instabilities in the regimes of astrophysical interest. In particular, effects as the presence of asymmetries due to current gradients, the influence of geometry and of shear flows must be explicitly evaluated. We have started a program of investigation on this subject, whose preliminary results are reported here.