Dynamics of the Central kpc in Barred Galaxies: Theory and Modeling
  The central kpc of barred galaxies exhibits a wealth of morphological information on different components with clear dynamical consequences. These include nuclear rings, spirals, bars, and more. We argue that this morphology is driven by large-scale stellar bars and analyze its consequences for gas dynamics and the distribution of star-forming regions. Specifically, we focus on gas flows in nested bar systems and study their origin, as well as the gravitational decoupling of gaseous nuclear bars with and without gas self-gravity. We find that the gas response in nested bars differs profoundly from that in single bars, and that no offset dust lanes form in the nuclear bars. 
Isaac Shlosman