In my qualitative model, I see the vacuum of space being a polarizable medium which is under tremendous pressure, and with very little viscosity. This PhysOrg article says scientists have lowered the 'lower bound' for the viscosity of the perfect fluid made up of the quark-gluon plasmas encountered in high energy particle accelerator collisions. Could that also apply to the 'viscosity' of the vacuum??? Time will tell, but I'll bet it does.
http://www.physorg.com/news/2012-01-liquid-.html "The physicists at Vienna UT found a way to include this anisotropy in their equations - and surprisingly the limit for the viscosity can be broken in this new model. "The viscosity depends on several other physical parameters, but it can be lower than the number previously considered to be the absolute lower bound", Dominik Steineder explains. The on-going quark-gluon-experiments at CERN will provide opportunities for testing the new theoretical predictions." Abstract here: http://prl.aps.org/abstract/PRL/v108/i2/e021601 -Mark
