Fluidity of finite nuclear matter - an experimental endeavour

The fluidity of a system is measured by the ratio of shear viscosity (η) to the entropy volume density (s). The smaller is the value of η/s, larger is the fluidity. In recent years, the quantity η/s has attracted a lot of theoretical and experimental investigations in different areas of physics. It is well defined for both relativistic and non-relativistic fluids and is important in connection with the physics of black hole, quark-gluon plasma (QGP), the low temperature quantum fluids etc. The temperature variation of η/s provides the crucial signature for liquid-gas phase transition in matter