Even more Einstein

My father was an engineer who was also an inspired photographer, but he had too little confidence and was not in the right milieu to realize himself in the artistic arena. It’s always been clear that my brother got the engineering genes while I got the artistic ones. If you consider our family, the article that recently came out in the Times about how first children are smarter and more dutiful is bullshit; my brother, younger, is much smarter and has led a much more normal (“responsible” is the word our parents would have used) life than I have. He always excelled in school, whereas I failed algebra and had to take a remedial class where I was the only girl in a roomful of hoods (at New Trier High School we pronounced that “hoooods” to rhyme with “dudes”). I got 900-something on my verbal SATs and 350 in math. The administration thought there could be a mistake. I knew there wasn’t.

If you asked my father to explain something, like “How does television work?” he’d give an interminable explanation accompanied by an elegant diagram drawn on one of the yellow pads that were always at hand. I was much more into the diagrams than the explanations, but my brother took everything in and ended up designing computers for IBM (a sign in his office read, “My job is so complicated even I don’t know what I do”) and now creates aerial surveillance software for the City of Tucson, complete with Web cams, which means he really is Big Brother.

This is a long way of getting back to the subject of “thought experiments,” which Walter Isaacson, whose book I’m reading about Einstein, has finally explained on page 138:

He calculated the properties of two light pulses emitted in opposite directions by a body at rest. He then calculated the properties of these light pulses when observed from a moving frame of reference. From this he came up with equations regarding the relationship between speed and time.

The result was an elegant conclusion: mass and energy are different manifestations of the same thing. There is a fundamental interchangeability between the two. As he put it in his paper, “The mass of a body is a measure of its energy content.”

Thus: energy equals mass times the square of the speed of light.

It makes me want to study physics. Almost.