Bar-halo interaction and bar growth

I show that strong bars can grow in galactic disks, even when the latter are immersed in halos whose mass within the disk radius is comparable to, or larger than, the mass of the disk. I argue that this is due to the response of the halo and in particular to the destabilizing influence of the halo resonant stars. Via this instability mechanism, the halo can stimulate, rather than restrain, the growth of the bar.