"We asked ourselves how the sensitive ultra-diffuse galaxies could survive at all in an environment as unsettled as a galaxy cluster," explains Carolin Wittmann, first author of the study.
Quantum FFF Theory has the answer: by different Fermion repelling Black Hole functions called EDMBHs ( Electric Dark Matter Black Holes.) crowded over the centers of these clusters.see: http://vixra.org/pdf/1707.0224v2.pdf
All galaxies are equipped with external so called GABHs 9Galaxy Ancho Black Holes,
( see image.)
SO in the center of galaxy clusters, these GABHs BHs are crowding all around everywhere
, they form a geometrical network of Dark Matter Galaxy Anchor Black Holes, polarizing the vacuum in between into multiple directions leading to Ultra Diffuse galaxies in the centers.
In between TWO BHs there is a vacuum sucking for plasma to form spiral galaxy formation, as we learned in the early universe by Herbig Haro systems with only two GABHs.
However in between three of more BHs there is a much more complex vacuum sucking for plasma creating diffuse open galaxies, just like our Magellanic dwarf galaxies.