I got distracted but now to the real reason I came to the SDMB this evening…
Non-newtonian liquid
Mythbusters did a piece on it using corn starch (and food dye… but that doesn’t matter). I also saw a piece on youtube using an unidentified additive. I don’t know if its corn starch or not.
Is there an additive that you could use that would be clear? Obviously, corn starch is out.
Shear-thickening fluids (dilatant fluids) are rare, so the choices are few. There are some that claim to be, but I’ve never seen them. Senson, a protective coating for metals, is one example; another might be the new generation of impact-resistant compounds like 3D0.
My guess is probably not, at least for a non-Newtonian liquid which behaves the same way (there’s only one way to be Newtonian, but countless ways to be non). Ooblek (cornstarch solution) behaves the way it does because of (relatively) long polymer strands in the fluid, which tangle together. Those polymers will also scatter light haphazardly, making the mixture appear to be milky white.
Anything approaching something of water? Even water you see in a pool that hasn’t been cleaned in a week? Just something that doesn’t look like milk?
As Chronos mentions, there are many ways to be non-Newtonian. IIRC, liquids like honey and highly viscous oils display non-Newtonian behavior. It “folds up” or “copils up” when you pour it into itself, making folds or self-coiling loops that rest on top of the fluid for a while before “melting” into the general body of the lquid. These liquids are definitely clear. But I wouldn’t try walking on them a la Mythbusters. Jearl Walker’s Flying Circus of Physics has mini-sections devoted to these liquids, with references.
In my youth there was a competitor to Silly Putty that sold under the name “Flubber” (This was for the first version of Disney’s The Absent Minded Professor/Flubber, a movie they’ve done three times now, to show you how long ago that was). It behaved much like Silly Putty, which is a non-Newtonian fluid that you probably could walk on. Only “Flubber” was transparent. I have no idea what it was made of.
Coiling behavior of non-newtonian (and clear) fluids:
http://www.iop.org/EJ/article/1742-5468/2006/10/N10001/jstat6_10_n10001.html
Hair Gel is apparently a non-newtonian fluid, although shear-thinning, rather than shear-thickening, as cornstarch + water is:
That’s a clear non-newtonian fluid.
More Shear-Thinning clear Newtonian fluids:
http://www.iop.org/EJ/article/1742-5468/2006/07/P07007/jstat6_07_p07007.html
I completely forgot about shampoos!
But all these examples are the opposite of that corn starch and water mix, aside from the “Flubber” of my youth. Bt I’ll see if I can find any other clear shear-thickening examples.
Googling “shear thickening” and “transparent” (It’s fun! Try it!) yields lots of papers like this one (which itself says that there are lots of papers like it) about shear-thickening fluids that are transparent:
http://www.physics.nyu.edu/pine/reprints/1998-09-00-JOR-Hu-I.pdf
This study uses “tris 2-hydroxyethyl) tallowackyl ammonium acetate” (TTAA) mixed with sodium salicylate, which is not something you run into every day (I love the “tallowackyl” part).
Here’s a buncha other papers:
Ah, the rare but beautiful quadruple post. Take it in kids, we don’t see these very often, especially such poignant ones rather than just ramblings.
:: Looks in awe ::