Star formation is generally inefficient because of self-regulation via energy and momentum input from massive stars’ lives and deaths. An important exception in the Milky Way is regions of high acceleration (or equivalently surface density), where stellar feedback is incapable of overcoming the self-gravity of dense gas clouds. I will discuss how dark matter may play an analogous gravitational role at high redshifts, allowing relatively efficient star formation over scales comparable to the masses of galaxies. This simple picture explains several aspects of high-redshift galaxy formation as revealed by JWST and why such efficient galaxy formation is not realized at lower redshifts. It also makes testable predictions, which I will describe, for regimes that JWST has not (yet) probed in detail and for evolution to lower redshifts.
