Galaxy Cluster Bulk Flows and Collision Velocities in QUMOND
  We examine the formation of clusters of galaxies in numerical simulations of
a QUMOND cosmogony with massive sterile neutrinos. Clusters formed in these
exploratory simulations develop higher velocities than those found in
{\Lambda}CDM simulations. The bulk motions of clusters attain about 1000 km/s
by low redshift, comparable to observations whereas {\Lambda}CDM simulated
clusters tend to fall short. Similarly, high pairwise velocities are common in
cluster-cluster collisions like the Bullet cluster. There is also a propensity
for the most massive clusters to be larger in QUMOND and to appear earlier than
in {\Lambda}CDM, potentially providing an explanation for 'pink elephants' like
El Gordo. However, it is not obvious that the cluster mass function can be
recovered.
