ON THE IDEAL INITIAL-VALUE PROBLEM FOR THE NEUTRAL SHEET

The ideal initial value problem for the neutral sheet is considered, with the emphasis on fieldwise-independent, infinitesimal velocity disturbances. It is shown analytically that cross-field velocity perturbations persist, and that they also set up fieldwise magnetic disturbances that grow algebraically in time. When these disturbances attain finite amplitude they should distort the neutral sheet configuration, and hence they could provide an alternative route by which magnetic reconnection can become turbulent. Some supporting numerical simulations, performed at large Lundquist numbers, are then described. In an Appendix the analysis is extended to include fieldwise-dependent disturbances.