Can Magnetic Super Fluids Create Gravity Waves?

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    Fluid Viscosity
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Discussion Overview

The discussion revolves around the properties of superfluid helium, particularly its viscosity and buoyancy, and explores the concept of magnetic superfluids and their potential to create gravity waves. The scope includes theoretical considerations and conceptual clarifications regarding fluid dynamics and superfluidity.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that superfluid helium, due to its lack of viscosity, would allow objects to fall at gravitational acceleration, questioning if this understanding is correct.
  • Another participant counters that viscosity is not the key factor for buoyancy, emphasizing the importance of density in this context.
  • A participant draws a parallel between superfluid helium and historical concepts of ether, questioning if a brick dropped in superfluid helium would fall at gravitational acceleration.
  • It is proposed that while drag does not arise solely from viscosity, an object would likely fall close to gravitational acceleration in superfluid helium.
  • A question is raised about whether an object would fall faster in superfluid helium compared to air at room temperature, and if Archimedes' principle applies to floating objects in superfluid helium.
  • Another participant states that liquid and superfluid helium would behave similarly for floating objects, noting differences in temperature and density, while also mentioning surface tension.
  • Participants express fascination with the unusual properties of superfluids, with one noting their initial skepticism about their existence.
  • There is a mention of magnetic superfluids and a speculative idea that accelerating a magnetic superfluid in a torus could lead to the generation of gravity waves.

Areas of Agreement / Disagreement

Participants express differing views on the implications of viscosity and density in superfluid helium, with no consensus reached on the effects of these properties on buoyancy and falling objects. The discussion on magnetic superfluids and their potential to create gravity waves remains speculative and unresolved.

Contextual Notes

Limitations include assumptions about the behavior of superfluid helium under various conditions, the dependence on definitions of viscosity and buoyancy, and the speculative nature of the idea regarding magnetic superfluids and gravity waves.

cragar
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If helium 4, when it is a super fluid has no viscosity then you shouldn't be able to float anything in it. And if you had a column of it you could drop a piece of wood in it and it would fall at g just like it would fall a vacuum. Am i thinking about this correctly.
 
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No. Viscosity is not the important factor when it comes to buoyancy. You are thinking of density, and superfluid helium certainly has density.
 
well I was just thinking that when people said that light moves through the ether. But then they said that the ether has no viscosity because if it did it would slow down the Earth and would eventually travel into the sun. So if He-4 has no viscosity could i still drop a brick into it and have it fall at g. Or Am i wrong.
 
It would not still fall at g on account of the fact that drag doesn't arise from viscosity alone. However, it would fall pretty darned close to g in all likelihood.
 
would it fall faster in a super fluid than in air at room temperature.
And if I wanted to float something in a super fluid would i just use Archimedes principle.
Would floating something in a super fluid be the same as liquid helium right before it became a super fluid?
 
For the purposes of floating things, liquid and superfluid helium would be practically the same; a difference because the superfluid is colder and denser, but that's about it. And let's not forget it still has surface tension!
 
okay i was just wondering about its bizarre properties , thanks for the answers everyone
 
Superfluid really are fantastic; I was convinced for ages they were science fiction!
 
ya they have very strange properties. And aren't they also super conductors.
 
  • #10
They are indeed! Very special things. No wonder Feynman devoted so much time to studying them!
 
  • #11
I have heard of people trying to make magnetic super fluids. The idea was that if the super fluid was magnetic you could accelerate it in a torus to relativistic speeds (using some sort of alternating magnetic field or something like it). This was thought to poetically make gravity waves or something. Anyone else heard of this?
 

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