Some meditations I wrote a while ago, at the end of my grad school admissions process. I’ll begin graduate studies in physics at Johns Hopkins this fall.
Dear Admissions Committees,
It’s hard to make admissions. Congratulations! Don’t you feel better now that you’re done for the year? That must be nice. All the possible admissions are lined up and you just choose the ones you want.
Well, now that you have admitted what you are going to admit, I have some things to admit, too. I didn’t admit them before because I wanted you to admit me. But now that we’re done with all that, I think we can just be honest with each other, at least a little.
I admit that I read Brian Greene when I was a kid. This is the first thing that you’re not supposed to admit. I’ve heard it many places – “Don’t tell them you were inspired by The Elegant Universe! Everyone tells that story. No one wants to hear about that.”
And I will admit it. No one wants to hear about that. No one wants to hear how I confronted those passages in the book that proclaim, with unapologetic authority, a string of certifiably insane conclusions about some twins who get a kick out of the improbable combination of spaceships, clocks, and meter sticks. No one wants to hear how, as Greene assaulted me with each new claim, I squirmed back and forth in my father’s armchair for hours, alternately flipping the book down to meditate on the dimples of our ceiling tiles and snatching back the pages for another greedy interrogation. I was an absurd blending of agitation, cogitation, and meaningful hand gestures as I attempted to conduct into harmony this mistuned orchestra of ideas. It was awe, I guess, but not the Grand Canyon, photos-from-Hubble, double-rainbow-all-the-way sort. It was the sort of awe Elmo would feel if you told him he’s actually a puppet, and some guy named Alonso had been controlling him by jamming a hand up his butt the last thirty years.
And man, you sure don’t want to hear how I sat on the edge of my chair in class the next day, bouncing my leg as if I had to pee, just because I wanted to get back home and see what was in the next chapter. You’d grimace, (really you would) if you were forced to stand by and listen to how I tried to relate everything in that book to the kids at school. Have you ever watched a skinny, pimply-faced nerd talking three times too fast as he tries to explain the diffraction limit to a running back? But listen – it didn’t matter. I was going to solve the MYSTERIES OF THE GOD DAMN UNIVERSE. You missed out, man. If you had only known to ask me, you could have learned all about how smart I was, when I was sixteen.
I admit that I am older now, and I’ve learned a lot. For example, blocks sliding down inclined planes. Dude, I am a total badass at that. The learned professors have taught me all sorts of stuff about it, and I can solve those block problems a lot of different ways. But here’s something not too many people admit – I think they’re fun.
Would you believe it? Blocks sliding down inclined planes are absolutely fascinating! Like, take this, for instance: you have a lumpy, three-dimensional hill. You take a ball and slide it down the hill, frictionlessly. Now, you go back up to the top and do the same thing over again – same ball and same hill – but this time you roll the ball down without slipping. And the question is: does the ball take the same path? Do you slide down a hill over the same route you roll down the hill? I admit it took me three months to figure this out. Three months! Not of constant work, but three months of germination before the answer sprouted. And when I gave a presentation on it to the physics club, I filled up three blackboards with math. All for a ball rolling down a hill.
Or take the brachistochrone. You remember that, of course. The brachistochrone is the hill you slide down to get from point A to point B as fast as possible. Finding it is a basic problem in the calculus of variations. But did you know it was solved by the Bernoullis in the seventeenth century, long before the calculus of variations existed?
If you take Snell’s law, it tells you how light bends when it goes from one medium to another – entering the water from the air, say. And by Fermat’s principle, it’s taking the fastest path. So you see, we can make a perfect analogy between an optical system and a mechanical one, both minimizing travel time, and Snell’s law applies equally well to both. If you start by understanding light, all the sudden you understand balls sliding down hills. And that’s how Bernoulli found the answer long before the techniques we now use even existed.
Did you ever realize that the brachistochrone shape changes depending on the size of the ball, or wonder what the answer is for tunnels going through the Earth? I admit an unhealthy fondness for such useless considerations as all that. And I admit that obsession with this trivia will probably compromise my usefulness as a single-minded researcher. I admit that I’m not ashamed of that, because blocks sliding down inclined planes are cooler than you ever imagined. That’s something I admit to thinking is worthwhile.
I admit that I don’t like lectures because ninety minutes is way too long to listen to you talking, and that I hate problem sets because, if you already know the answer, why don’t you just tell me already?
I admit that I am, paradoxically, both egotistical and insecure about my own ability. I admit that I have no idea what it actually means to do some meaningful work, and you’ve got a long road ahead of you if you’re going to try to turn me into a productive researcher. I admit that I’m practically computer illiterate, that I still don’t get what partition functions are for, and that I will probably daydream about quantum-mechanical midget porn during your colloquium.
Here. I will make my worst admission of all. I admit that I am not really a physicist; I’m just curious. I want to learn about the spin-statistics theorem, yeah. That sounds really interesting to me. But I also want to know why a hard-boiled egg stands up when you spin it, how a plant seed knows which way to grow, and why a circle saturates the isoperimetric inequality.
I admit that I don’t care if I’m the first to figure something out. I admit I don’t need to be a part of a great scientific establishment or to feel like I’m on a search for truth. I admit it’s enough, for me, just to be puzzled about something, to be squirming back and forth in my father’s armchair.
You wanna hear the next half of the Brian Greene story? Because it gets better. Six or seven years after my first encounter with that book, I’m at Caltech, learning such intricacies as Ehrenhfest’s theorem or retarded potentials (that’s a real thing!). And around this time, Brian Greene writes a new book, a kid’s book, about a teenager who goes flying around a black hole in a spaceship and gets sent a thousand years into the future.
Greene goes on a book tour, and his next stop is Caltech. I’m on the staff of the newspaper, so I send an email asking for an interview. An hour before the public talk begins, I’m finally seated in a little room backstage in Beckman auditorium, feeling my stomach knot a little as I start my conversation with Brian Greene.
“It’s actually a cautionary tale that’s closer to what actually happens in science,” Greene tells me about Icarus. To be honest, his new book kind of sucks. He’s out of his depth, and I don’t care about the book that much. But I thought I should ask anyway. “What happens in science?” he continues, “Well, we go forward into the unknown, we learn new things, and sometimes that drags us, sometimes kicking and screaming, into a new reality.”
His response to my question about Icarus feels a little bit canned. Greene says,
“I have a strong sense from talking to people that for many, science is this abstract, cold, aloof body of knowledge that sometimes may make a difference in their lives if it yields a new medical technique or yields a new piece of technological gadgetry. But otherwise, science is something that people stay away from.
“My point is to try to convince people and open up to people the fact that science goes far beyond that. It can touch you in an emotional way. It can help you have a different connection to the world and the universe around you, whether you’re the next Einstein or whether you’re just someone who wants this to be a part of your life. As I’ll discuss tonight, I think that science is as important to a full life as music and art and literature and theater, and I think books like this can help people begin to recognize that.”
No! How can this be? Brian Greene doesn’t understand his own book. Let me explain. When I was sixteen, I didn’t just discover Brian Greene. I discovered Sibelius, too. And I used to lie flat on the carpet downstairs, listening to the second symphony over and over and feeling the blood in my veins. It was nothing like reading physics! And it shouldn’t be. It’s its own thing – a completely separate vital experience. The pursuit I learned about in Dad’s armchair should not be latched on to the back of “music and art and literature and theater”. Greene is talking about physics as Grand-Canyon-awe. I never even liked the Grand Canyon that much. I’m still Elmo. And now I’m forced to realize that the guy who showed me all this stuff in the first place is totally confused about it what it is.
All right, fine. I admit I still like Brian Greene. I haven’t read his new book or anything, but honestly it was a pretty good interview, and I like the guy. But I admit I had to go back after that, and re-examine some stuff. And what I learned is that Brian Greene was immaterial. The Elegant Universe was immaterial. It was special relativity itself that had mattered. I admit that was a revelation to me.
Let’s get down to it. I admit that I hate you for judging me, you admissions committees. Because how could you know? How could you decide what you do and don’t want to admit, just from that little admissions material I sent you? That’s none of it – nothing at all. It didn’t have me in it because it wasn’t supposed to. I wasn’t supposed to admit myself, and so how can you choose to admit me? That’s the thing when you’re in our position. Between you and me, even with all our admissions, there is really no way to know.
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