Superfluid is a quantum fluid that flows on its own and so it seems as if it has zero viscosity.
Helium becomes a superfluid at very low temperatures (less than -270°C). The transition from a normal fluid to a superfluid is studied by considering Bose statistics (instead of Fermi statistics) and the process is explained as being due to [Bose-Einstein condensation]
? (Bosonization).
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