[ExI] Discontent with the path physics is taking

[Brent Neal]

On 20 Aug, 2011, at 10:52, Kelly Anderson wrote:
>> 
> 
> I weep for my ignorance too... but I can only take physics to the
> point that the mass media is willing to go... I'm not going to brush
> up on my very rusty mathematics and go back to grad school at this
> point :-)

That's a tough position. I'm pretty confident that I'd have a hard time brushing back up on rusty math too, and I finished my grad school out. What you don't use decays with time, and its been over a decade since I've needed to put pen to paper to solve a QM scattering problem or something of that ilk.  :)

> 
> So Brent, why do you think the mass media never even talks about this
> stuff? Don't us Monday morning physicists deserve to hear about this
> cool stuff too? :-)  Is it just too hard to grok the basic concepts?
> I've never even heard the phrases "Soft Matter" or "Polymer Physics".

Yeah, I honestly don't know why these areas aren't considered 'popular' - there's some pretty clever work being done there. I honestly believe that you don't need to be particularly numerate in order to write a good popular book on these topics - its much more important to have an excellent facility at explaining things conceptually, but with a wicked accuracy and attention to detail.  So maybe you should write these books? :)  With de Gennes having passed away a few years back, I'd be willing to bet the market is ripe for a good biography of his work.

Primarily, soft matter physics is the study of order-disorder phenomena in condensed matter at levels of order between crystalline solids and the classical liquids.  de Gennes particularly studied the physics of liquid crystals and the isotropic-nematic transition. More broadly (and this gets into the nature of my current research), soft matter includes polymer dynamics - the behavior of macromolecules in dilute solutions and in melts and their crystallization from those melts, as well as  order-disorder phenomena in multicomponent systems, colloids, and gels.  

Practically speaking, this is how we clarify polypropylene that you use to store your food. (i.e. Ziploc food containers, Gladware food containers.)  Polypropylene on its own is pretty much opaque. By controlling the dynamics of its crystallization, however, we can make the polyproylene crystallites always smaller than 200 nm, so they won't scatter light in the visible bands. 

So, no, I don't think the physics here is particularly hard. The only advanced math I've seen anywhere in the literature here (i.e., beyond a run-of-the-mill partial differential equation) is a stochastic DE, and I felt that was probably unnecessary. My background is in condensed matter and I found it exceptionally accessible. If you wanted to check out a book or two from your library, the two I felt were the best were Gert Strobl's book, and Rubenstein and Colby's book.  (One is titled "Polymer Physics" and the other is "The Physics of Polymers."  And boy, I wish I could remember which is which without recourse to Amazon...)  You might be better off starting with Rubenstein. I recall Strobl being mathematically intense and weak on conceptualization.

> 
> I am glad to hear that there is a lot of good work going on, and I
> suspected that there was. We of the great unwashed masses just don't
> hear about it.

I was thinking about this a lot as a response to this thread. I suspect strongly now that there is a lot going on in physics that the atoms-and-particles set would not recognize (or acknowledge, if they did recognize) as physics. But ultimately, if your goal is to find the basis of measurement of a physical phenomenon in order to construct rigorous mathematical models of the behavior with a goal of understanding some underlying behavior, then you're doing physics, no matter what your degree or job title says. Physics is a science, and thus is a skillset and problem solving formalism, not a static body of knowledge.

B


--
Brent Neal, Ph.D.
http://brentn.freeshell.org
<brentn at freeshell.org>