  We propose that flow fluctuations have the same origin as transverse momentum
fluctuations. The common source of these fluctuations is the spatially
inhomogeneous initial state that drives hydrodynamic flow. Longitudinal
correlations from an early Glasma stage followed by hydrodynamic flow
quantitatively account for many features of multiplicity and $p_t$ fluctuation
data. We develop a framework for studying flow and its fluctuations in this
picture. We then compute elliptic and triangular flow fluctuations, and study
their connections to the ridge.
