ooblick magick

[nibot]

We all know that cornstarch + water (otherwise known as ooblick) is amazing stuff. However, these guys in texas at the center for nonlinear dynamics have taken it to a new level. If nothing else, you should check out the paper and definitely the movie. I wonder if this could be repeated just using a loudspeaker and function generator? Yet another reason to procrastinate on studying for finals!

[edit: you're too late! I guess the movie was "slashdotted," as it's no longer available from their web page. )-: edit2: nevermind, they fixed it.]

[edit3: here's an experiment with solitons that you can do on the surface of a pool: Falaco Solitons. Check out the paper gr-qc/0101098 in arXiv. "String theorists take note, for the structure consists of a pair of topological 2-dimensional rotational defects in a surface of discontinuity, globally connected and stabilized by a 1 dimensional topological defect or string."]

On another note, I'm curious how much of antenna theory can be co-opted to make antennas for sound. A yagi for sound seems a bit unlikely, but parabolic reflectors certainly work, and it seems that there ought to be some magic with cavity resonators.

Comments

[shamster.livejournal.com]

Why do y'all think it was done using a loudspeaker? The paper says nothing more than "shaker".

btw - any knowledge of where the 'full' paper is published? I recall most phys-rev-lett's as shorter versions of the real deal.

[nibot.livejournal.com]

I'm not saying that they did it with a loudspeaker, but that it might be possible with a loudspeaker.

[shamster.livejournal.com]

Hmmm... maybe. Doubtful. 1 mm displacement is big. A very big load for a loudspeaker. Especially when you're moving a mass of corn starch suspension.

It really doesn't matter, because THIS (http://www.visualprosthesis.com/javoice.htm) is way cooler anyhow!

[nibot.livejournal.com]

A very big load for a loudspeaker.

I suppose you're right. Other suggestions?

Mass-spring suspension system at the resonant frequency? sounds annoying.

I have some old code for producing sound output in linux that might be handy: http://splorg.org/people/tobin/projects/dtmf/

[shamster.livejournal.com]

It is possible to rig up systems with oscillating vibrators (think of a poorly balanced rotating rod) that could drive a platter as if on a cam... of sorts. I'm doubting, but it's possible. Their big paper, if tracked down, will most likely reveal the answer. A very spiffy 'paint-shaker' at 120 Hz seems more likely.