We investigate the gravitational implosion of magnetized matter by studying
the inhomogeneous collapse of a weakly magnetized Tolman-Bondi spacetime. The
role of the field is analyzed by looking at the convergence of neighboring
particle worldlines. In particular, we identify the magnetically related
stresses in the Raychaudhuri equation and use the Tolman-Bondi metric to
evaluate their impact on the collapsing dust. We find that, despite the low
energy level of the field, the Lorentz force dominates the advanced stages of
the collapse, leading to a strongly anisotropic contraction. In addition, of
all the magnetic stresses, those that resist the collapse are found to grow
faster.Comment: 6 pages, RevTex; v2: physical interpretation of the results slightly
changed, references added, version accepted in Phys. Rev. D (2006