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Physics Redux

I spent today at the University of Chicago’s James Franck Institute, first giving a talk on finance and then listening to many people tell me about the interesting solid/liquid state physics they are doing, theory as well as experiment.

I had forgotten over the years how interesting active physics is. The most fascinating thing I saw was an experiment in which they let loose from a height a small drop of liquid onto a solid base while taking 1 million photos per second of the collision (camera cost = 100k, 2 cameras). People have known for decades that a drop splatters when it hits the ground and send up a corona of little droplets. These guys discovered, and demonstrated in a video that required no computer analysis but just your eyes, what nobody expected — that if you lower the air pressure in the tube in which the collision takes place to a fraction of an atmosphere, then the drop doesn’t splatter at all; when it hits the ground it spreads out into flat pancake. No air, no corona. Somehow the air is essential for the corona to form. No one knew that before the experiment and no one knows why. They had expected quite the opposite: that the air pressure damps the corona, that the corona would be larger at low pressure. Instead they found that the corona requires the presence of air.

It was inspiring to see postdocs and students investigating phenomena that are puzzling and real, phenomena that will be true for ever, that won’t change. I kind of admired the timelessness of it. You could see that they were partaking of a long heritage of careful research, that they were part of a culture. This was about content, not computation or style.


On another note: On the plane to Chicago I reread bits of Brave New World on my iPad 1. The book is very impressive in it’s humor and in its parody of capitalist consumerism (said he disparagingly as he tapped the keys of his already obsolete iPad 1). One of many excerpts:

“Strange,” mused the Director, as they turned away, “strange to think that even in Our Ford’s day most games were played without more apparatus than a ball or two and a few sticks and perhaps a bit of netting. Imagine the folly of allowing people to play elaborate games which do nothing whatever to increase consumption. It’s madness. Nowadays the Controllers won’t approve of any new game unless it can be shown that it requires at least as much apparatus as the most complicated of existing games.”


“We condition the masses to hate the country,” concluded the Director. “But simultaneously we condition them to love all country sports. At the same time, we see to it that all country sports shall entail the use of elaborate apparatus. So that they consume manufactured articles as well as transport. Hence those electric shocks.”

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