MIT physicists capture audio of a "perfect fluid", people put it on their Soundcloud playlists

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So is the perfect fluid like a superfluid where the superfluid component is at 100%?


Unless I’m misunderstanding, that soundcloud clip is what happens when you play a sweeping tone through a volume of this perfect fluid. So this is the “sound of” that fluid only in the sense that a recording of Hanson performing Mmm Bop in a specific cave is “what caves sound like”.

It might be more edifying to hear a familiar sound played through the same medium. Or at least to hear what the unmodulated scanning tone sounds like.


Yes, I think that’s right!

Yeah, good point. In a way it throws to a weird phenomenological question of what the sound of anything is, too. The idea of playing Mmmmbop in a cave to illustrate the sound of a cave is a usefully absurd example to clarify the stakes; but now you’ve got me realizing I don’t have any practical philosophical guide to saying what the sound of a cave is. (I’m not saying such a definition doesn’t exist – merely that I’m ignorant of what it might be.) Or the other thing I thought is: What’s the “sound” of a pipe organ? The noise it makes when it’s being played and air is rushing through it? Or the noise it makes when I throw rocks at the wooden base? Or the noise it makes when it’s sitting unplayed in an empty room?


@bobtato @Clive_T
I’m wandering if the old ‘chestnut’ that wind has no sound could be a useful tool for deciphering this? The sound of wind is is the effect that it has on an environment or object i.e. moving the leaves of a tree - a kinda mid to high end chaotic modulating white noise, or through a flute - the result of exiting a resonating tube/body.

Wind is both the medium of audio transmission and the fluid like motion of that medium.

A common digital audio technique is to analogue (with a mic) record a blast of white noise into a space such as a cathedral and produce an IR (impulse response) that then can be used digitally to re-create the reverberations of that space and be mapped onto any input sound to simulate that sound being in the actual space. The IR creates no sound until it is ‘excited’ by an audio input. The presence of @Clive_T pipe organ sitting in silence would effect any sound in the space by it’s volume and reflective presence.

Without reading the research the description of the perfect fluid having the lowest possible viscosity flow(?!) seems to need more explanation i.e. is this flow modulating in time or some weird fixed quantum state or both at the same time!

Many respectable physicists said that they weren’t going to stand for this, partly because it was a debasement of science, but mostly because they didn’t get invited to those sorts of parties.


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Also, the geometry of the chamber can have an influence which would be interesting to disentangle. (“Can you hear the shape of a drum?” is a classic article.)

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