By John Archibald Wheeler with Kenneth Ford: W.W. Norton, 1998
“How come the quantum? How come existence?” John Wheeler begins and ends his autobiography with these questions. One of the great physicists of our time, he is also one of the great physics teachers of our time. He popularized the term “black hole” for those mysterious crunches of spacetime, pushing their existence and some of their properties into public consciousness.
Wheeler is perhaps best known for his work in gravitation where he helped bring an abstruse and highly mathematical subject back near the center of modern physics. His tome Gravitation which he co-authored with Charles Misner and Kip Thorne has become a classic textbook. But Wheeler also did important work in particle theory and nuclear physics. He worked with Niels Bohr on the theory of nuclear structure. During World War II he worked on the design of the Hanford nuclear reactors which produced the plutonium used in nuclear weapons. Later he worked on the development of the hydrogen bomb weapons, much to the disapproval of most of his academic colleagues.
Wheeler has always been a patriot-scientist, in the old-fashioned sense of the word. One reason for this may have been his experience while working on the Hanford reactors. His younger brother had been drafted and was serving as an infantryman in Italy. His brother did not know what John was actually working on, but he could surmise it was important war work. He sent a last postcard to John with the single phrase “Hurry Up.” Several weeks later he was killed in his foxhole and left to rot for eighteen months until his body was discovered.
It is as a teacher that Wheeler may be best remembered. A Professor at Princeton University since 1938 he has also held a Professorship at the University of Texas since 1976. One of Wheeler’s early graduate students at Princeton was Richard Feynman. In those days Wheeler was interested in how much time he was spending at teaching, research, and administration and he would often time his activities. At Wheeler’s first meeting with Feynman, he pulled out his watch and put it on the table. Feynman noticed this but said nothing. Afterwards Feynman bought a dollar pocket watch. At their second meeting, when Wheeler put his watch on the table, Feynman, with a completely serious face, pulled out his watch and snuggled it right next to Wheeler’s watch. Wheeler was taken aback and didn’t know what to think, but then he began to laugh and pretty soon they were both laughing so hard they had tears in their eyes. After that they got along famously.
Simplifying a matter to its essence and devising an apt phrase to describe it has always been Wheeler’s forte. “Black Holes” is just one of his phrases. In his elementary text book Spacetime Physics, written with Edwin Taylor, he pushed space and time into one word, as they should be, and pushed momentum and energy into one word, momenergy. Einstein was once asked if he could explain the main features of general relativity while standing on one foot. Wheeler did it with: “Spacetime tells matter how to move. Matter tells spacetime how to curve.” The ancient Pythagoreans speculated that everything comes from number. Wheeler speculates that existence comes from logic which he states as “It from bit.”
I can’t fail to mention two other Wheeler books. A Journey Into Gravity and Spacetime is a Scientific American Library book accessible to a broad audience (but most will have to struggle with it). It opens with a wonderful line: “Nothing more strongly animates this book than a passionate belief that this is our universe, our museum of wonder and beauty, our cathedral.” At Home in the Universe is a collection of essays on many topics. One of my favorites is “Be the Best to Give the Most.”
In his autobiography Wheeler writes: “I have to admit that I never stop thinking about physics… How come existence? How come the quantum? What is my relation to the universe and its laws? Can spacetime be all that there is? Is there an end to time?… These questions have nothing to do with my religious convictions, which center on guides to living, guides to civilized intercourse among humans. The deep questions that I wrestle with belong to science, as I define it, not religion.”
You will just have to read the book to find out what geons and quantum foam are.
Reviewed by David Park