What is a Superfluid?

Superfluid is a state of matter characterized by a complete lack of viscosity. If a superfluid is placed in a ring-shaped container, it can flow endlessly because there is no friction. For example, when the liquid helium is below 2.17 K, the internal friction coefficient becomes zero, and the liquid helium can flow through small holes or capillaries with a radius of ten to the fifth power square centimeter. It's called Superfluid.

Superfluid

Super fluid is an ideal fluid with strange properties at ultra-low temperature, that is, there is no viscosity at all in the fluid. Superfluid required temperature ratio

Experiment find-outs,

One of the important applications of superfluids is the Dilution refrigerator.

Superfluid Helium-4 has been successfully used as a quantum solvent for spectroscopy in the chemical field. Helium drops in superflow

Space-time may be some form of superfluid. Superfluid is a state of matter, completely lacking in viscosity, and because of the absence of friction, it can flow endlessly without losing energy. According to the theory of Riberati and Marchenoni, space and time as this special material form also has extraordinary characteristics, just like sound propagates in the air, it provides a medium that allows waves and Photons propagate ^[3]

• "Superfluid" / (US) by Shen Xingyang (1982).-Beijing: Science Press

• Mendelssohn, Kurt Alfred Georg (1966). The Quest for Absolute Zero: The Meaning of Low Temperature Physics . New York: World University Library. McGraw-Hill.

• Hagen Kleinert, Gauge Fields in Condensed Matter , Vol. I, "SUPERFLOW AND VORTEX LINES", pp. 1742, World Scientific (Singapore, 1989); Paperback ISBN 9971-5-0210-0 (also available online here)