dr. weinberg, what is this picture on the front of your book? >> that's a picture of lake austin as seen from our boat dock. i do most of my work at home in an office overlooking the lake. and so i have a certain feeling of connection with lake austin. >> why would a nobel prize-winning physicist of science put a lake on the front of his book? >> well, it is what i look at while i'm working, but also, you know, being a scientist, especially a few theoretical physicist, it's a little unworldly. and the sounds of the lake, especially in summer, the boats going up and down the lake playing music brings me back a little bit to the real world, the world of human affairs, which is i think healthy. >> well -- >> that's what i was trying to do in this book, in many of the essays, to peek out of the ivory tower of debt, something to say about the real world. >> let's peek back into the ivory tower. what's the purpose of studying physics? >> well, there are many reasons for doing it. it has enormous practical value, of course. not the kind of physics i do