Multiple populations in globular clusters: constraints from kinematics
  and dynamics
  We discuss constraints on the formation of multiple populations in globular
clusters (GCs) imposed by their present-day kinematics (velocity dispersion and
anisotropy) and spatial distribution. We argue that the observational evidence
collected so far in the outer parts of clusters is generally consistent with an
enriched population forming more centrally concentrated compared to the
primordial population, in agreement with all the scenarios proposed to date (in
some cases by design), but not sufficient to favour a particular scenario. We
highlight that the differential rotation of subpopulations is a signature that
may provide crucial new constraints and allow us to distinguish between various
scenarios. Finally, we discuss the spatial distribution of subpopulations in
the central regions of GCs and speculate that mass segregation between
subpopulations may be due to a difference in their binary fraction.
