  We investigate the maximum coding rate achievable on a two-user broadcast
channel for the case where a common message is transmitted with feedback using
either fixed-blocklength codes or variable-length codes. For the
fixed-blocklength-code setup, we establish nonasymptotic converse and
achievability bounds. An asymptotic analysis of these bounds reveals that
feedback improves the second-order term compared to the no-feedback case. In
particular, for a certain class of antisymmetric broadcast channels, we show
that the dispersion is halved. For the variable-length-code setup, we
demonstrate that the channel dispersion is zero.
