Galileo's Pendulum

[ I assembled two new bookshelves, so I have room for my science books for the first time in a long while. In honor of the occasion, I’m writing a few personal essays inspired by books. Here’s the first installment. ]

A book is sometimes more than itself. Books famously can help us get through hard times in life, lead us toward empathy with those different than ourselves, shore up faith in humanity when it’s needed, tear down creaky concepts when they need demolishing, or simply provide a break from the stresses of life. And sometimes books are entangled in our lives thanks to the person who gave them to us, or when we first read them, or some combination of all of these. I confess I’m a bit of a book hoarder, keeping books long after they are likely to be useful to me again on the off chance that maybe, some day, they will be exactly what I need.

Physics books aren’t stereotypically the life-changing variety, though I’ve certainly had my mind expanded or changed from reading them. However, on occasion a book can be symbolic as well as useful, and one of those books for me is the classic general relativity text simply titled Gravitation.

General relativity — the modern theory of gravitation — was my first grown-up scientific love, and my most enduring one. Much of my doctoral research involved general relativity (often just abbreviated GR by aficionados), and my favorite topics to write about as a professional journalist grew out of the theory: black holes, gravitational waves, and of course modern cosmology, the study of the entire universe. Before a theory describing the structure of space and time, cosmology was a branch of philosophy and theology; while obviously there are still philosophical and theological aspects, we can put an age on the cosmos and measure the relative amounts of matter, dark matter, dark energy, and light … all thanks to general relativity.[1]

I don’t have as many general relativity books as I once had, but I’ve kept a few that are either favorites or have some essential discussions in them.[2] The best of the lot came around too late to be useful when I was learning: Gravity by James Hartle was published in 2003 when I was in my fourth year of graduate school, but it’s often the first book I open these days when I need to check my thinking on something in GR. Robert M. Wald’s book is the most aggressively mathematical of the set, which suited the kind of work I did in my doctoral work; Sean Carroll’s Spacetime and Geometry (which also came out later in my grad career) balances the physics and math very well. In other words, each book has its reasons, and each has helped me understand the theory of relativity better.

The biggest book — possibly the biggest I own on any topic — is Gravitation by Charles Misner, Kip Thorne, and John Archibald Wheeler, and it was the first “real” GR book I ever bought. Sure, I had a textbook (A Short Course in General Relativity, the slim purple volume you can see peeking out among the fatter texts), but I bought Gravitation during my college years to help me with my research, not because it was required for a class. I spent my combined birthday and Christmas money from my grandparents on it, because I was pretty broke as a college student.

We are all unreliable narrators of our own life stories. I don’t remember exactly when I bought Gravitation, how much I paid for it (I bought it new), or what holiday or other occasion prompted me to haul such a huge book to Tarkio, Missouri, where my mother’s parents lived. And while I’d like to say that I brought it to show them only out of gratitude, the truth is that I was showing off too: “look at me, I am a physicist who understands the contents of this great big complicated book.” Don’t get me wrong: the gratitude was there too, but if it had only been that a thank-you note would have sufficed.

Neither grandparent was a scientist, but they both cared deeply about education.[3] My grandfather Leland, not content merely to be the first of his family to get a college degree, got two bachelor’s degrees and a doctorate in education; he split his career between teaching high school music, college music, serving as a college administrator, and then after “retiring” leading an alternative high school and helping organize the construction of a new town library. I’m not sure technically what my grandmother Connie’s college degree was in, but she was fluent in French and Spanish and had taught herself Italian, German, and Greek. She also painted, and taught French, Spanish, and art at a high school in a nearby town. I get my habit of humming random musical phrases at odd times from my grandfather, and my workaholism and liberal-arts interest in every subject from both of them.

They are both gone now. My grandmother died after a difficult few years of cancer and cancer treatments; my grandfather died less than a year later, perhaps feeling he didn’t need to carry the burden of the world on his shoulders anymore. But I remember my grandfather sitting in his favorite chair holding Gravitation in his lap, reading the first two chapters to understand what the book was about and why it was so important to his grandson. My grandmother, who rarely sat down except to eat, didn’t read it, but interrogated me about its contents. She always was interested in cosmology and astronomy, and loved to talk to me about them.[4] I was proud of my book and my new physics knowledge, but they were proud of me too.

Older and wiser me knows that Gravitation wasn’t the best choice so early on in my studies, but it was hard to resist. MTW (as physicists often call it, for the initials of the authors) is engagingly written, is well illustrated, and has a lot of topics that aren’t touched on in other books. It’s a little out of date now — the copyright is 1973 — but the authors tried to create a readable and thorough book on a challenging subject. Looking at it today, I see things I didn’t think much about then, including some pointlessly sexist vignettes that begin each section,[5] and the readability of the text is marred by the fact that it takes for bloody ever to find any useful information. In other words, it’s a frustrating book, with good and bad aspects, which I guess gives it an edge over most technical books that end up just being boring.

But in many ways it was an appropriate book for my grandparents to provide for me, though they didn’t know that’s what I would spend their money on. Gravitation, for all its faults, is an attempt to create a special kind of book, full of intriguing diagrams and pictures and sidebars with additional information or biographical sketches of general relativity researchers. While it’s certainly a graduate-level discussion of a mathematical physics topic, it’s also trying to be something more: a beautiful book, a readable book, an elegant book. But for me, the connection to my grandparents — and their commitment to education both for their families and everyone — helps make the book greater than it is.

Relative(ity)

Grandfather, grandmother – children of the Depression
I am theirs, as much as they are mine;
Teachers demanding fealty to the life of learning,
A loyalty I eagerly, willingly gave.
They bought my books, remembering old struggles —
Their own poverty in payment for the life of learning
The payment of energy to bring them asymptotic (academic) freedom
Deconfined from family failure – unreasonable destiny of drink or despair.
They bought my books, paying for my own freedom of mind.
I brought their gifts to them, proud and shy
Telling them what I learned – embryonic physicist
Full of relativity to share with relatives
But my frame of reference is mine, theirs was theirs;
We are symmetrical (not identical).
Now they are both ash – my own writing
Will never lie in their laps as my big (proud) textbooks did.
But I am theirs, as much as they are mine:
Symmetry – relative(ity).

Notes

1. As always, our language describing these things is imprecise. Our observable universe is 13.8 billion years old, but that doesn’t necessarily mean everything that is began at that time. Certainly we know the universe goes on well past the limits of our ability to see. But I digress.
2. I also own some older, more historical books — including Einstein’s own writing on GR — but those are on another shelf.
3. As does my father’s mother, who is still alive. I promise to write about her another day, and about my father’s father, who died when I was still a kid.
4. Though her interest was never quite balanced with finding reliable sources for information. That’s a common problem with being widely interested in everything.
5. Example: the start of Part IV begins “Wherein the reader is seduced into marriage with the most elegant temptress of all — Geometrodynamics — and learns from her the magic potions and incantations that control the universe.”