In lieu of an abstract, here is a brief excerpt of the content:

What Is Physics? Miles Blencowe When I was a kid growing up with my younger brother Ben in Vancouver, Canada, our grandfather Sam would come and stay with us for extended periods . Ben and I liked to raid Granddad Sam’s room for loose change in order to provide for our snack habit, taking advantage of the seemingly limitless supply of quarters, dimes, and nickels to be found on his desk and on the floor, a result of him regularly emptying his trouser pockets of all their contents.Also scattered on Granddad Sam’s desk and floor were sheets and sheets of paper covered with strange squiggly-looking symbols. I remember asking Sam what the symbols were about, and he would chuckle and then proceed to read out some of the symbols at random: “Eat-a Jane-not . . .” Despite sounding like gobbledygook to our ears, somehow at the time I knew that one day when I grew up, I would be doing the same thing as Granddad Sam, deriving pleasure from writing strange symbols on paper. Well, that is exactly what happened: like my grandfather, I am now what is called a physicist. And I have a daughter, Cecilia, who likes to ask me what the symbols mean on the pages of calculations to be found on my desk.Cecilia has just started to learn about physics at school and has been coming home with some very interesting questions. But the question she asks me most often has to do with a physics problem that I have been working on for a while now. In fact, as I sit at my desk writing this, she comes up behind me and taps me on the shoulder:“Daddy,have you figured out how to be in two places at once yet?” In a nutshell, physicists use mathematics as a language to describe and understand the behavior of the matter and energy world around us. By the world around us, we mean the whole universe—from the microscopic realm of subatomic particles to the macroscopic realm of clusters of galaxies and everything in between. No single physicist has enough time in the day to work on under- What Is Physics? 255 standing every aspect of the universe, so as a community we divide into smaller groups and, depending on our interests, concentrate on trying to gain a deeper understanding of some aspect of the world around us. Also, physicists tend to be either experimentalists—working with instruments like particle accelerators, telescopes, and other types of equipment to measure precisely the behavior of the world—or theorists like myself, who attempt to explain using mathematics as a precise language the results of experiments, as well as predict the outcomes of future experiments. In order to illustrate what physics is,I would like to tell you about what I have been working on—that question Cecilia keeps teasingly bringing up, the one about being in two places at once.The one thing I won’t do, however, is use the convenient language of mathematics to explain my work, since I suspect most of you are not used to applying the algebra you started learning in math class to describe the world around you as a practicing physicist does. This would be a little like showing you a music score and expecting you to hear the music in your head while reading the score. Instead, I will try to explain what physics is by using only words and analogies, and by concentrating on one example that I hope you will find as fascinating as I do! But it is worth bearing in mind that, just as it is much more efficient to play music on an instrument such as a violin by reading a score than reading a description of how the music is to be played in words, so too it is much more effective to give our physics explanations of the world around us in terms of mathematics than in words. So, keep learning and practicing your mathematics! Let us begin with an analogy. Take a look at figure 1, which shows gently flowing water in a cool stream somewhere in the White Mountains of New Hampshire.Imagine that you yourself are squatting on the stream bank contemplating the flowing water,particularly the ripples on the surface of the water.As you look at the ripples,you wonder what causes them.This wondering is exactly what physicists do when they work on a project...

pdf

Back To Top

This website uses cookies to ensure you get the best experience on our website. Without cookies your experience may not be seamless.