Monday, May 19, 2003

Reading Einstein

I recently reviewed Thomas Levenson's Einstein in Berlin (Bantam) in the San Francisco Chronicle---in fact, right here. I was asked to do this review, as opposed to suggesting the book myself, though if I had known about it I might well have asked to do it. I've been fascinated by Einstein, and recently had been dipping into a selection of his own non-scientific essays, called Ideas and Opinions. But I don't write reviews for myself. I write them for readers of the Chronicle, and specifically readers who might be interested in reading the book I'm reviewing.

Of course I can't know who they are, but I can make educated guesses. Who would be interested in a book on Einstein? First of all, I guessed, readers interested in physics and the history of twentieth century science. Because Einstein was and remains famous as a pacifist, there would be readers interested in that aspect, particularly in this time of fresh debate and heartache over issues of war and peace. And there would be people tempted just by the magic of Einstein's name, his image as the model of scientific genius, his celebrity status. Just a few years ago, Time Magazine picked him as the most influential figure of the twentieth century. He's the kind of known name with a little known life that probably attracts readers who simply like reading biographies. These days, there are lots of those people; biographies are high on the list of the most popular nonfiction books.

So I tried to answer questions each of these "readers" might have, as well as answer one of my own---a question that had occurred to me recently: how did Einstein reconcile his pacifism with his letter to FDR that, history says, strongly suggested that the U.S. develop an atomic bomb before Germany did?

For readers of biography and people specifically interested in Einstein, I wrote that this wasn't actually a biography. It was limited to Einstein's years in Berlin, from just before World War I until just before World War II. And at least half of the book was about Berlin in those years, and the various figures that dominated German history, politics, and the arts as well as science---including following Adolf Hitler from his years as a low-ranking, generally enthusiastic and incredibly lucky soldier in World War I. Readers interested in physics and the history of science would find that those topics were treated with economy and precision.

I tried to answer my own question, even though (as I wrote) it wasn't one that Levenson ever asked. The bare facts of it are partly in his book, and partly in another book I read as I was preparing this review, called Einstein in America by Jamie Sayen (Crown, 1985). I liked the Sayen book very much, and it was a delightful companion to Levenson's. They were very interesting to read one after the other.

Though Einstein was pretty much out of the loop on atomic research by the late 1930s, there were few physicists who believed an atomic bomb was possible or practical. Some didn't believe it until Hiroshima. Einstein had already escaped Germany and was vacationing on Long Island in the summer of 1939 when his old friend, Leo Szilard, told him of his own research which suggested that a chain reaction was possible. Einstein immediately realized what this meant, and the two discussed what to do. At a second meeting, Einstein dictated a letter to President Roosevelt, which Szilard rewrote, and possibly others worked on, but that Einstein signed. It warned that an atomic bomb might be possible and that German scientists appeared to be working along lines that would lead them to that conclusion as well. He noted that Germany had stopped the export of uranium from Czechoslovakian mines. He requested that the U.S. government "establish contact with the scientists working on nuclear physics, and that it help subsidize research and the procurement of uranium," Sayen writes.

President Roosevelt responded to this letter by appointing a team to study the matter, and they quickly recommended the actions suggested in the letter, but did little more after that . Szilard got Einstein to write a second letter in 1940 "designed to rekindle Roosevelt's interest in uranium research" and to suggest that the results of the research of Szilard and others be kept secret.

There's an interesting sidelight here, that appears in none of these books, but which I ran across in reading about H.G. Wells for my "Soul of the Future/of Star Trek" projects. Wells is credited with being the first to foresee the possibility of atomic bombs, in his 1913 novel, The World Set Free. It remains one of the more astonishing acts of prophecy in imaginative fiction.

By the 1940s so many science fiction writers were exploding atomic bombs in their stories that pulp magazine editors were complaining, and as real thing got nearer but was still a secret project, the U.S. government was knocking on their doors. But Wells had anticipated the first attempts to figure out if such a device was practicable by about thirty years. When he wrote about it, the atomic bomb didn't even yet have a name. Wells named it. Even dropping a bomb-any kind of bomb-from an airplane was a new idea, and it would be only a small factor in World War I, which had not yet begun. Science didn't even yet have a generally accepted rough sketch of the atom. The Rutherford-Bohr model-the atom as a miniature solar system that was still be drawn on the blackboard when I was in high school-didn't exist yet.

All that had happened was the discovery of radioactivity and radium. Wells apparently understood more of the implications of Einstein's E=mc2 formula, announced in 1905, than did many scientists. But from these and a few other bare beginnings, he made a series of astonishingly accurate surmises in his fictional history of the past that hadn't happened yet. For example, that the neutron would be the trigger of an explosive reaction (discovered in 1932), and the existence of twin atoms, or isotopes (the actual discoverer of that got the Nobel Prize in 1921.)

He speculated on the properties of a substance yet to be discovered that he called carolinium. It turned out to be plutonium. He also nailed the year of a preliminary discovery. In his future history, artificial radioactivity is produced for the first time in 1933. It was.

Wells also got a lot of things wrong, but he did dramatize an atomic war, and that caught the attention of Leo Szilard, who happened to read Wells novel in 1932. It impressed him, even though he wasn't yet working on nuclear physics. But by 1939 he was, and once he suddenly realized how to set up a nuclear chain reaction, he thought at once that it must be kept secret. He knew what this discovery could mean---"and I knew it because I had read H.G. Wells," he said.

So Szilard prevailed on Einstein to suggest keeping the research secret. He did, and it was. (And a decade after reading Wells, Szilard was working with Enrico Fermi at the University of Chicago where they created the first nuclear chain reaction.) But that turns out to probably be the extent of Einstein's influence and involvement in decisions concerning the atomic bomb.

Even after Einstein's second letter, the U.S. government, still officially neutral, kept uranium research limited. Then in the fall of 1941 a report by British scientists concluded that atomic weapons could very well be created and used in the current war. This report was shown to Vannevar Bush, Chairman of the National Defense Research Committee, who passed it on. "It was this information, not Einstein's two letters," Sayen writes," which inspired the United State government to make a full commitment to the development of atomic weapons by the creation of the Manhattan Project on December 6, 1941."

Einstein of course was so worried about Nazi Germany developing and using atomic bombs that he hoped the U.S. could counter that threat with its own bombs. Einstein knew what American and British leaders either didn't know or didn't care to dwell on-that in addition to conquering Europe, the Nazis were rounding up and killing Jews (including members of his own family.) Though Einstein's reasons for recognizing the Nazis as a powerful evil that had to be opposed by force may seem self-evident, Levenson's portraits of Germany provides the weight of evidence that Einstein saw during his years there.

After Germany was defeated, Einstein wrote a third letter to President Roosevelt, again at the passionate instigation of Leo Szilard. It was an introduction to a longer letter by Szilard, that Einstein felt he could not read because he didn't have Szilard's security clearance. The substance of Szilard's document however was a warning (possibly inspired by Wells?) of a nuclear arms race, particularly if the U.S. used the atomic bomb on Japan. Roosevelt died shortly after the letter was delivered, and the efforts of Szilard and other nuclear physicists to persuade the Truman administration not to drop the atomic bomb on Japanese cities were apparently never taken very seriously.

"Einstein never wavered in his conviction that use of atomic weapons on Japan was morally unjustifiable," Sayen concludes. "Although Einstein never forgave the German people for their acquiescence to the Nazi slaughter of Jews, he would never have endorsed the use of atomic bombs on Germany once it became known that the German atomic bomb project had failed. The bomb was a defensive weapon and no amount of Germany barbarity could justify American barbarity when the danger of a similar German bomb was removed."

Another sidelight to the reviewing process: there was another biographically-based book on Einstein that came out around the same time as the Levenson book, and I got a copy so I might review the two together. But I found I had little constructive to say about Einstein: The Passions of a Scientist by Barry Parker (Prometheus Books), except that its treatment of Einstein is chronological (whereas Levenson skips around a bit, which caused me some confusion). I was searching for a delicate way to say that since it's so short and the writing so simple, it could be used as a kind of Cliff's Notes chronology, so the reader could keep events that Levenson describes in the proper order. It was in fact useful to me for this purpose, but such faint praise didn't assume enough priority to make it into the final 800 words. Otherwise I found the Parker book no fun to read at all, with its deadened short sentences and graceless vocabulary.

It does have pictures, though, which Levenson's book oddly lacks. It's especially strange considering that Levenson is a TV producer, and his "Nova" treatment of Einstein is quite visual (the animation of Einstein's thought experiments leading to his physics insights were particularly useful to me.) In his book, he describes several photographs, and the architecture of a building named after Einstein. But no photos in the book. Perhaps that's a separate project.

Postscript: By Kowincidence, the Einstein Papers---his scientific and non-scientific writings and a lot more---have just been made available online at this site.

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