Archive for February 20th, 2011

Memory of soap films

February 20, 2011

Long back, somewhere, I read something to this effect: “If your life does not allow you to throw stones in ponds and look at the waves, then there is something wrong with it”. I guess the same is true for soap films too. And, some people do have the luxury to make soap films, wonder at them, and then publish papers about them. Here is one of the latest in that category:

A soap bubble is spherical, but a wire frame dipped in soapy water can make other shapes. A research group has now tracked in detail how a film switches from one shape to another when the wire frame is slowly modified. As predicted, the transition point depends on the starting shape, as if the film “remembered” its past. The simple experiment, detailed in the March Physical Review E, is a clear, visual demonstration of a delicately balanced type of equilibrium known as metastability, and it may provide some insights into the way bubbles evolve in solid foams.

The write-up also reminded me of Prof. Eric Lord, his friend Prof. Alan Mackay and the amazing posters of periodic minimal surfaces that they once  exhibited at IISc, Department of Metallurgy (currently, Materials Engineering).

Update: And, what to say about people who drill holes in refrigerators and image icicles as they are forming? Some people get to have all the fun in the world, I tell ya!

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Some thoughts on teaching

February 20, 2011

I am half-way through  Jay Parini‘s The art of teaching, a slim volume of about 160 pages. Parini, being a writer, finds lots of similarities between teaching and writing; and, with his literary and poetic training, finds lots of similarities between theatre and classroom performance:

Teaching and writing have a lot in common here. “In creating,” wrote James Russell Lowell in ” A Fable for Critics”,” “the only hard thing’s to begin.” In the classroom, starting over can feel daunting. Teaching–again, like writing–is a brave act of self-presentation, and with every new class, the need to reinvent oneself is vividly, even scarily, at hand. In fact, good teachers have no choice but to consider their public selves in a calculated fashion; a subject I address in detail later in this volume. The classroom is a form of theater, and the teacher must play various roles, often in an exaggerated manner: wise man, fool, tempter, comforter, coach, confessor. And that is just for starters. (…) In fact, there is nothing natural about teaching; (…)

Of course, some of the advice and suggestions that Parini gives are meant for those who teach literature and humanities; but one can see the spirit behind those, and modify them for teaching in other branches as well.

Parini is also not a great fan of examinations, tests and quizes:

I was always suspicious of the classroom as a testing ground for intelligence, a place for sorting the “good” from the “bad” students. The idea of the academic world as a place of competition repelled me. To be frank, it still does, and I never feel happy with students or colleagues who seem excessively interested in grading, in putting up barriers to jump across. I hate exams, and I find quizzes an annoyance–for me as well as the students who must take them. Test-oriented teaching strikes me as anti-educational, a kind of unpleasant game that subverts the real aim of education: to waken a student to his or her potential, and to pursue a subject of considerable importance without restrictions imposed by anything except the inherent demands of the material.

On the whole, a nice book; strongly recommended if you are interested in teaching or started teaching recently.