Anonymous ID: 81a902 Feb. 1, 2020, 7:52 p.m. No.7997751   ๐Ÿ—„๏ธ.is ๐Ÿ”—kun   >>7762 >>7784

>>7997740

No, I am the comforter.

Helium 4 - why is it important?

 

frictionless bearings?

In reality though, not all particles stay in the condensate even at absolute zero where, classically, particles are expected to stand still. Instead, interaction-induced quantum fluctuations make the particles collide, unavoidably expelling some particles out of the condensate, a phenomenon called "quantum depletion."

 

This effect is incredibly strong in superfluid helium-4, the first known superfluid, such that 90% of the particles are expelled out of the condensate. However, in extremely dilute, ultracold atomic gases, which form the typical Bose-Einstein condensates (BEC) we know, the effect is much weaker, almost negligible.

 

https://www.sciencedaily.com/releases/2020/01/200123095846.htm