Posts Tagged ‘Historiography’

Redactions

Oppenheimer, Unredacted: Part II – Reading the Lost Transcripts

Friday, January 16th, 2015

This is the second and final part (Part II) of my story about the lost Oppenheimer transcripts. Click here for Part I, which concerns the origin of the transcripts, the unintuitive aspects of their redaction, and the unorthodox archival practice that led me to find their location in 2009.


Oppenheimer photograph courtesy of the Emilio Segrè Visual Archive.

The Oppenheimer security hearing transcript is not exactly beach reading. Aside from its length (the redacted version alone is some 690,000 words, which makes it considerably longer than War and Peace), it is also a jumble of witnesses, testimonies, and distinct topics. It is also somewhat of a bore, as there is incredible repetition, and unless you know the context of the time very well, the specific arguments that are focused on can seem arbitrary, pedantic, and confusing, even without the additional burden of some of the content having been deleted by the censor.

The most damning problem for Oppenheimer at his 1954 hearing involved his conduct during the so-called “Chevalier incident,” in which a fellow-traveler colleague of his at Berkeley, Haakon Chevalier, approached Oppenheimer at a party in late 1942 or early 1943 at the behest of another scientist (a physicist named George Eltenton) who wanted to see if Oppenheimer was interested in passing on classified information to the Soviet Union. Oppenheimer, in his recollection, told Chevalier in no uncertain terms that this was a bad idea. Later, Oppenheimer went to a member of the Manhattan Project security team and told him about the incident, calling attention to Eltenton as a security risk, but also trying to not to make too big of a deal of the entire matter. Confronted with the idea of Soviet spying on the atomic bomb project, the security men of course did not take it so lightly, and pressed Oppenheimer for more details, such as the name of the intermediary, Chevalier, which Oppenheimer did not want to give since he claimed Chevalier had nothing truly to do with Soviet spying. Over the course of several years, the security agents re-interviewed Oppenheimer, trying to clarify exactly what had happened. Oppenheimer gave contradictory answers, seemingly to shield his friends from official scrutiny and its consequences. At his hearing, when asked whether he had lied to security officials, Oppenheimer admitted that he had. When asked why, Oppenheimer gave what was become the most damning testimony at a hearing about his character: “Because I was an idiot.” Not a good answer to have to give under any context, much less McCarthyism, much less when you are known to be brilliant.

I mention this only to highlight the difference between what is in the published transcript and what is not. The newly unredacted information does not touch on the Chevalier incident much at all. That is, it does not shed any new light on the central question of relevance towards Oppenheimer’s security clearance. What does it shed light on? We can lump its topics into roughly three categories.

One of the censor's trickier redactions, in which he removed a trouble word, and substituted a different word in its place. "Principle" was too close to a secret, but"idea" was acceptable.

One of the censor’s trickier redactions, in which he removed a trouble word, and substituted a different word in its place. “Principle” was too close to a secret, but”idea” was acceptable. (JB = James Beckerley.)

The first category concerns the creation of the hydrogen bomb. Oppenheimer had been on a committee that had opposed a “crash” program to build the H-bomb in 1949. This was at a time when it was unclear that such a weapon could be built at all. The then-favored design (later dubbed the “Classical Super”) had many problems with it, and didn’t seem like it was likely to work. It seemed to also require huge quantities of a rare isotope of hydrogen, tritium, the production of which could only be done in nuclear reactors at the expense of producing plutonium.For Oppenheimer and many others, there was a strong technical reason to not rush into an H-bomb program: it wasn’t clear that the bomb could be built, and preparing the materials for such a bomb would decrease the rate of producing regular fission bombs.

How much plutonium would be lost in pursuing the Super? This is an area the newly-reduced transcript does enlighten us. Gordon Dean, Chairman of the Atomic Energy Commission from 1950 to 1953, explained that:

You don’t decide to manufacture something that has never been invented. Nothing had been invented. No one had any idea what the cost of this thing would be in terms of plutonium bombs. As the debate or discussions waged in the fall of 1949, we had so little information that it was very difficult to know whether this was the wise thing to do to go after a bomb that might cost us anywhere from 20 plutonium bombs up to 80 plutonium bombs, and then after 2 or 3 years effort find that ft didn’t work. That was the kind of problem. So there were some economics in this thing.

The underlined section was removed from the published transcript. This does contribute to the debate at the time — if researching the Super meant depriving the US stockpile of 20-80 fission bombs, that is indeed a high price. We might ask: Why was it redacted? Because the censor wanted to undercut Oppenheimer’s position? Probably not — if the censor had wanted to do that, he would have removed a lot more than just those numbers. More likely it is because you can work backwards from those numbers how much plutonium was in US nuclear weapons at that time, or, conversely, how much tritium they were talking about. My understanding is that every gram of tritium you make is a gram of plutonium you don’t make; if you know that the bombs at the time had about 6 kg of plutonium in them, then you can see they are talking about producing between 120 and 480 kg of tritium. Should this have been classified? It seems benign at the moment, but this was still a period of a “race” for thermonuclear weapons, and nearly everything about these weapons was, rightly or wrongly, classified.

Redaction of a long section on the development of the Teller-Ulam design. Ulam's name was almost totally (but not entirely) removed from the transcript, sometimes very deliberately and specifically. The orange pencil shows the mark of the censor, as does the "Delete, JB" on the right.

Redaction of a long section on the development of the Teller-Ulam design. Ulam’s name was almost totally (but not entirely) removed from the transcript, sometimes very deliberately and specifically. The orange pencil shows the mark of the censor, as does the “Delete, JB” on the right.

But the hydrogen bomb could be built. In the spring of 1951, physicists Edward Teller and Stanislaw Ulam hit upon a new way to build a hydrogen bomb. It was, from the point of view of the weapons physicists, a totally different approach. Whereas the “Classical Super” required using an atomic bomb to start a small amount of fusion reactions that would then propagate through a long tube of fusion fuel, the “Equilibrium Super,” as the so-called Teller-Ulam design was known at the time, involved using the radiation of an atomic bomb to compress a capsule of fusion fuel to very high densities before trying to ignite it. To a layman the distinction may seem minor, but the point is that many of the scientists involved with the work felt this was really quite a big conceptual leap, and that this had political consequences.

The differences between the redacted and un-redacted transcript shows a censor who tried, perhaps in vain, to dance around this topic. The censor clearly wanted to make sure the reader knew that the hydrogen bomb design developed in 1951 (the “Equilibrium Super”) was a very different thing than the one on the table in 1949 (the “Classical Super”), because this is a clear part of the argument in Oppenheimer’s favor. But the censor also evidently feared being too coy about what the differences between the 1949 and 1951 designs were, as such was the entire “secret” of the hydrogen bomb. For example, here is a section where Oppenheimer testified on this point, early on in the hearing:

In the spring of 1951, there were some inventions made. They were not discoveries, really; they were inventions, new ideas, and from then on it became clear that this was a program which was bound to succeed. It might not succeed at first shot; you might make mistakes, but for the first time it was solid. It was not on the end; it wasn’t so that every time you calculated it it was yes or not, but it came out that you knew that you could do not. It was just a question of how rapidly and how well and I am amazed at the speed at which this actually went after we learned what to do. Ulam and Teller had some very bright ideas; why none of us had them earlier, I cannot explain, except that invention is a somewhat erratic thing.

Again, what is underlined above was removed from the original. Read the sentences without them and they still have the same essential meaning: Oppenheimer is arguing that the 1951 design was very different than the 1949 one. Put them back in, and the meaning only deepens a little, adding a little more specifics and context, but does not change. One still understands Oppenheimer’s point, and much is left in to emphasize its import — Oppenheimer only opposed the H-bomb when it wasn’t clear that an H-bomb could be made.

Why remove such lines in the first place? A judgment call, perhaps, about not wanting to reveal that the “secret” H-bomb was not a new scientific fact, but a clever application of a new idea. The censor could have probably justified removing more under the security guidelines, but took pains to maintain coherency in the testimony. In one place, the physicist Hans Bethe referred to Teller and Ulam’s work as a new “principle,” and the censor re-worded this to “idea” instead. A subtle change, but certainly done in the name of security, to shift attention away from the nature of the H-bomb “secret.”

Early 1954 was a tricky time for hydrogen bomb classification. The US had detonated its first H-bomb in 1952, but not told anyone. In March 1954, a second hydrogen bomb was detonated as the “Bravo test.” Radioactive fallout rained down on inhabited atolls in the Marshall Islands, as well as a Japanese fishing boat, making the fact of it being a thermonuclear test undeniable. The Soviet Union had detonated a weapon that used fusion reactions in 1953, but did not appear to know about the Teller-Ulam design. As a result, US classification policy on the H-bomb was extremely conservative and sometimes contradictory; that the US had tested an H-bomb was admitted, but whether it was ready to drop any of them was not.

JRO redaction Rabi mermaids

In this category I would also attribute I.I. Rabi’s “mermaids” redaction, mentioned earlier. As published, it was:

We have an A-bomb and a whole series of it, *** and what more do you want, mermaids?

Restored, it is:

We have an A-bomb and a whole series of it, and we have a whole series of Super bombs, and what more do you want, mermaids?

To the censor, the removed section implied, perhaps, that there was no single H-bomb design, but rather a generalized arrangement that could be applied to many different weapons (which were being tested during Operation Castle, which was taking place at the same time as these hearings). This is a tricky distinction for a layman, but important for a weapons designer — and it is the eyes of the weapon designer that the censor feared, in this instance.

The censor’s fear of foreign scientists scouring the Oppenheimer hearing transcripts for clues as to the H-bomb’s design was not, incidentally, unwarranted. In the United Kingdom, scientists compiled a secret file full of extracts from the (redacted) Oppenheimer transcript that reflected on the nature of the successful H-bomb design. So at least one country was watching. As for the Soviet Union, they detonated their first H-bomb in 1955, having figured out the essential aspects of the Teller-Ulam design by the spring of 1954 (there is still scholarly uncertainty as to the exact chronology of the Soviet H-bomb development, and whether it was an entirely indigenous creation).

Project Vista cover page

The second major category of deletions pertained to Oppenheimer’s role in advising on the use of tactical nuclear weapons in Europe. This involved his participation in Project Vista, a study conducted in 1951-1952 by Caltech for the US Army. Vista was about the defense of continental Europe against overwhelming Soviet ground forces, and Oppenheimer’s section concerned the use of atomic bombs towards this end. (It was named after the hotel that the summer study took place in.)

Oppenheimer’s chapter (“Chapter 5: Atomic Warfare”) concluded that small, tactical fission bombs could be successfully used to repel Soviet forces. In doing so, it also argued against a reliance on weapons that could only be used against urban targets — like the H-bomb. The US Air Force attempted to suppress the Vista report, because it seemed to advocate that the Army into their turf and their budget. It was one of the many things that made the Air Force sour on Oppenheimer.1

In order to emphasize that Oppenheimer was not opposed to the hydrogen bomb on the basis of entirely moralistic reasons, a lot of the discussions at the hearing initiated by his counsel related to his stance on tactical nuclear weapons. They wanted it to be clear that Oppenheimer was not “soft” on Communism and the USSR. Arguably, Oppenheimer’s position was sometimes more hawkish than those of the H-bomb advocates. Oppenheimer wanted a nuclear arsenal that the US would feel capable of using, as opposed to a strategic arsenal that would only lead to a deterrence stalemate.

Another classic Cold War redaction: what we know about the enemy, even if we don't know anything.

Another classic Cold War redaction: what we know about the enemy, even if we don’t know anything.

The debate of strategic arms versus tactical nukes is one that would become a common point of discussion from the 1960s onward, but in 1954 it was still confined largely to classified circles because they pertained to actual US nuclear war plans in place at the time and the future of the US nuclear arsenal. Much of this discussion is still visible in the redacted transcript, but with less emphasis and detail than in the un-redacted original. The essential point — that in the end, the US military pursued both of these strategies simultaneously, and that Oppenheimer was no peacenik — gets filled out a more clearly in the un-redacted version.

Among the sentences that got redacted are long portions that describe the Vista project, its importance, and the fact that it was taken very seriously. It is unfortunate that these were removed, because they would definitely have changed the perception that Oppenheimer was acting on purely “moral” reasons against the hydrogen bomb. Oppenheimer opposed the hydrogen bomb, but he did so, in part, because he advocated making hundreds of smaller fission bombs. Other statements removed is a remark by General Roscoe Charles Wilson about something he heard Curtis LeMay say: “I remember his saying most vigorously that they couldn’t make them too big for him.” One can appreciate why the censor might want to remove such a thing, as a rather unflattering bit of hearsay about the head of the Strategic Air Command. Lest one think that these removals would only help Oppenheimer’s case, many of the other lines removed from Wilson’s testimony concerned the fact that the Air Force did find that they had plenty of strategic targets for multi-megaton bombs — removed, no doubt, because it shed light on US targeting strategy, but the sort of thing that generally went against Oppenheimer’s argument.

Similarly, John McCloy testified that Oppenheimer’s views were fairly hawkish at the time:

I have the impression that he [Oppenheimer], with one or two others, was somewhat more, shall I say, militant than some of the other members of the group. I think I remember very well that he said, for example, that we would have to contemplate and keep our minds open for all sorts of eventualities in this thing even to the point of preventative war.

Did Oppenheimer really advocate preventative nuclear war with the Soviet Union? It’s not impossible — his views in the 1950s could be all over the place, something that makes him a difficult figure to fit into neat boxes. In retrospect, we have made Oppenheimer into an all-knowing, all-rational sage of the nuclear age, but the historical record shows someone more complicated than that. Why would the censor remove the above? Probably because it would be seen as inflammatory to US policy, potentially because it might shed light on actual nuclear policy discussions. In this case, this line potentially could have had a strong impact on the post-hearing memory of Oppenheimer, had it been released, but probably not a positive one.

JRO redaction Groves on Rosenbergs

Lastly, there are a few removals for miscellaneous reasons relating to the conduct of the hearings themselves. As I pointed out at the beginning, when the witnesses at the security hearing took the stand, they were told that their responses would be “strictly confidential,” and not published. This was to encourage maximum candor on their part. When the decision was made to publish the transcript, each of the witnesses were contacted individually to be told this and were asked if there was anything they would not want made public. There is evidence of a few removals for this reason.

General Leslie Groves, the head of the Manhattan Project during World War II, said a number of things that were not classified but would have been embarrassing or controversial if they appeared in print. For example, he was emphatic that “the British Government deliberately lied about [Klaus] Fuchs,” the German physicist who had been part of the British delegation to Los Alamos and was, as it later became known, a Soviet spy. Groves also opined on the importance of Fuchs’ espionage versus that of the Rosenbergs:

I think the data that went out in the case of the Rosenbergs was of minor value. I would never say that publicly. Again that is something while it is not secret, I think should be kept very quiet, because irrespective of the value of that in the overall picture, the Rosenbergs deserved to hang, and I would not like to see anything that would make people say General Groves thinks they didn’t do much damage after all.

Even Groves’ comment at the time made it clear that this was not something he wanted circulated publicly. Should this information have been removed? It is a tricky question. If Groves had known what he said would be printed, he never would have said any of it. Ultimately this becomes not an issue of classification, but one of propriety. Its inclusion does not affect issues relating to Oppenheimer’s clearance. It is part of a much longer rant on Groves’ part about the British, something he was prone to do when confronted with the fact that the worst cases of nuclear secrets being lost occurred on his watch.

In one slightly smaller category, there is at least evidence of one erroneous, accidental removal. There is a line, on page 129 of the GPO version, which, when restored, looks like this: “Having that assumption in mind at the time Lomanitz joined the secret project, did you tell the security officers anything that you knew about Lomanitz’s background?” The restored material contains nothing classified, or even interesting, and its removal is not noted in the official “concordance” of deleted material produced by the Atomic Energy Commission censor. So why was it removed? Looking at the originals, we find that the entire contents of the deleted material comprise the last line of the page. It looks like it got cut off on accident, and marked as a redaction. Such is perhaps further evidence of the rushed effort that resulted in the transcript being published.

* * *

Does the newly released material give historians new insight into J. Robert Oppenheimer? In my view: not really. At best, they may address some persistent public misconceptions about Oppenheimer, but ones that have long since been redressed by historians, and ones that even the redacted transcript makes clear, if one takes the time to read it carefully and deeply. The general public has long perceived Oppenheimer to be a dovish martyr, but even a cursory reading of the actual transcripts makes it clear that this is not quite right — he was something more complex, more duplicitous, more self-serving.

Oppenheimer's two TIME magazine covers: as ascendent atomic expert (1948), and casualty of the security state (1954).

Oppenheimer’s two TIME magazine covers: as ascendent atomic expert (1948), and casualty of the security state (1954).

If the redacted sentences had been released in 1954, they would have fleshed out a little more of the story behind the H-bomb and behind Oppenheimer’s advocacy for tactical nuclear weapons. They would have emphasized more strongly that Oppenheimer opposed the H-bomb not just for moral reasons, but for technical reasons, and that rather than opposing the development of atomic armaments, Oppenheimer supported them vigorously — and even supported using them in future conflicts. The latter aspect, in particular, might have changed a bit the public’s perception of Oppenheimer at the time. Oppenheimer was not a dove, he was just a different sort of hawk, which somewhat reduces the idea of Oppenheimer as a martyr against the warmongers. This latter notion (Oppenheimer as anti-nuke) is a common perception of Oppenheimer, even today, though much scholarly work has tried to go against this notion for several decades.

The recent declassification of the transcript does not tell us anything we essentially did not already know from other sources, including the many of the wonderfully-researched histories of this period published in recent years by scholars such as Jeremy BernsteinKai Bird, David Cassidy, Gregg Herken, Priscilla McMillan, Richard Polenberg, Richard Rhodes, Sam SchweberMartin Sherwin, and Charles Thorpe, among others. These new revelations do not drastically revise our understanding of Oppenheimer or his security clearing. He looks no more nor less of a “security risk” than he did in the redacted version of the transcripts.

At the same conference where I initially was inspired to search for the conference, Polenberg asked the group assembled: how would we remember Oppenheimer today, if he had not had his security clearance stripped after the hearing? His own answer is that we would probably have longer focused on the more negative aspects of Oppenheimer’s personality and perspectives. We’d see him not as a dove, but as a different flavor of hawk. He’d see him as someone who was willing to turn in his friends to the FBI, if it served his interests. We’d see him as someone who, again and again, wanted to be accepted by the politicians and the generals. We would see more of his role as an enabler of the Cold War arms race, not just his attempts at tamping it down. By revoking the clearance, Oppenheimer’s enemies may have crushed his soul, but they made him a martyr in the process.

Headlines from 1954 regarding Beckerley and his split with the Atomic Energy Commission — and his turn as a secrecy critic.

Headlines from 1954 regarding Beckerley and his split with the Atomic Energy Commission — and his turn as a secrecy critic.

But just because these transcripts don’t give us much of a revision on Oppenheimer, or the conduct of his security hearing, doesn’t mean they are not  instructive. For one thing, they shed a good deal of light on the process of secrecy itself — and it is only by getting the full story, the record of deletions, that one can pass judgment on whether the secrecy was used responsibility or inappropriately.

In my view, the erasures appear to have been done responsibly. They do not greatly obscure the ultimate arguments for or against Oppenheimer’s character, and primarily hew to legitimate security concerns for early 1954. The choice of what to remove and what to keep was done not by one of Oppenheimer’s enemies, but by Dr. James G. Beckerley, a physicist who was at the time the Director of the Atomic Energy Commission’s Division of Classification. His initials (“JB”) can be found next to many of the specific deletions in some of the volumes. Beckerley was no rabid anti-Communist or promoter of secrecy. He was a moderate, one who often felt that the AEC’s security rules were highly problematic, and believed that only careful and sane application of classification rules (as opposed to zealous or haphazard) would lead to a stronger nation. As it was, he resigned his job in May 1954, not long after the Oppenheimer hearing, and became an outspoken critic of nuclear secrecy. We do not know Beckerley’s personal opinions on Oppenheimer, but in every other aspect of his work he seems not to be the classification villain that one expects of a Cold War drama.

So it is perhaps not surprising that his deletions from the Oppenheimer transcript are, in retrospect, pretty reasonable, if viewed in context. They do not seem overtly politicized, especially in the way that Beckerley carefully carved up some of the problematic statements so that their ultimate argument still came out, even if the classified details did not. Most were plausibly done in the name of security, according to the security concerns of early 1954. In fact, the amount of discussion of the H-bomb’s development allowed in the final transcript is rather remarkable — very little has in fact been removed on this key topic. A few of the removals, were done in the name of propriety, removed because of the changing status of the transcript from “confidential” to public record. None of the comments removed for non-security reasons seem to have had any bearing on the question of Oppenheimer’s character and loyalty, though they are certainly interesting. Groves’ comments on the Rosenbergs, for example, is completely fascinating — but not relevant to Oppenheimer’s case.

Two frames from a 1961 photo session with Oppenheimer by Ulli Steltzer. "He was shy of the camera and I never got more than 12 shots. It is hard to say which expression is most typical." More on this image, here.

Two frames from a 1961 photo session with Oppenheimer by Ulli Steltzer. “He was shy of the camera and I never got more than 12 shots. It is hard to say which expression is most typical.” More on this image, here.

In this case, I disagree with the conclusions given by the other historians in the New York Times article about the release. I don’t think the removals bolster Oppenheimer’s case, and I don’t think there is any evidence to suggest that the redactions were made to aid the government’s case. We are accustomed to a story about classification that involves bad guys hiding the truth. Sometimes that is a narrative that works well with the facts — classification can, and has often been, abused. But in my (someday) forthcoming book, I argue that part of this impression of “the censor” as a shadowy, faceless, draconian “enemy” is just what happens when we, on the outside, are not privy to the logic on the “inside.”

It is somewhat tautological to say that secrecy regimes hide their own logic by the very secrecy they impose, but it is actually a somewhat subtle point for thinking about how they work. When you are outside of a secrecy regime, you can’t always see why it acts the way it does, and it is easy to see it as an oppositional entity designed to thwart you. Peeling back the layers, which is what historians can do many years after the fact, often reveals a more subtle and complex organizational discussion going on. In the case of these transcripts, it is clear, I think, that Beckerley was trying his best to satisfy both the security requirements of the day regarding the key features of the newly-invented hydrogen bomb, as well as avoid saying too much about US nuclear force postures in Europe. And, just as key, he was juggling the problem of witnesses who had been told their original testimony would be confidential. There is no evil intent in these actions, that I can see.

Did these redacted sentences need to be kept classified for 60 years? Of course not. And by releasing them in full, the Department of Energy explicitly agrees that these transcripts contain nothing classified as of today. But they weren’t being hoarded for decades because of their lasting security relevance — they were just forgotten about. These volumes probably could have been fully declassified at least as early as 1992, and probably would have, had the declassification effort not gotten shelved.

Still, it is important that they are finally released. Even a negative result is a result, and even an empty archive can tell us something positive. Knowing that the un-redacted transcripts contain nothing that would either exculpate, nor incriminate, J. Robert Oppenheimer is itself something to know. Secrecy does not just hide information: it creates a vacuum into which doubt, paranoia, fear, and fantasy are harbored. Removing the secrecy here has, at least, removed one last veil and source of uncertainty from the Oppenheimer affair.

Notes
  1. On Vista, see esp. Patrick McCray, “Project Vista, Caltech, and the dilemmas of Lee DuBridge,” Historical Studies in the Physical and Biological Sciences 34, no. 2: 339-370. The Vista cover page image comes from a heavily redacted copy of the report that was given to be by Sam Schweber. []
Redactions

General Groves’ secret history

Friday, September 5th, 2014

The first history of the Manhattan Project that was ever published was the famous Smyth Report, which was made public just three days after the bombing of Nagasaki. But the heavily-redacted Smyth Report understandably left a lot out, even if it did give a good general overview of the work that had been done to make the bomb. Deep within the secret files of the Manhattan Project, though, was another, classified history of the atomic bomb. This was General Leslie Groves’ Manhattan District History. This wasn’t a history that Groves ever intended to publish — it was an internal record-keeping system for someone who knew that over the course of his life, he (and others) would need to be able to occasionally look up information about the decisions made during the making of the atomic bomb, and that wading through the thousands of miscellaneous papers associated with the project wouldn’t cut it.

Manhattan District History - Book 2 - Vol 5 - cover

Groves’ concern with documentation warms this historian’s heart, but it’s worth noting that he wasn’t making this for posterity. Groves repeatedly emphasized both during the project and afterwards that he was afraid of being challenged after the fact. With the great secrecy of the Manhattan Project, and its “black” budget, high priority rating, and its lack of tolerance for any external interference, came a great responsibility. Groves knew that he had made enemies and was doing controversial things. There was a chance, even if everything worked correctly (and help him if it didn’t!), that all of his actions would land him in front of Congress, repeatedly testifying about whether he made bad decisions, abused public trust, and wasted money. And if he was asked, years later, about the work of one part of the project, how would he know how to answer? Better to have a record of decisions put into one place, should he need to look it up later, and before all of the scientists scattered to the wind in the postwar. He might also have been thinking about the memoir he would someday write: his 1962 book, Now it Can Be Told, clearly leans heavily on his secret history in some places.

Groves didn’t write the thing himself, of course. Despite his reputation for micromanagement, he had his limits. Instead, the overall project was managed by an editor, Gavin Hadden, a civil employee for the Army Corps of Engineers. Individual chapters and sections were written by people who had worked in the various divisions in question. Unlike the Smyth Report, the history chapters were not necessarily written near-contemporaneously with the work — most of the work appears to have been started after the war ended, some parts appear to have not been finished until 1948 or so.

General Groves not amused

In early August 1945 — before the bombs had been dropped — a guide outlining the precise goals and form of the history was finalized. It explained that:

Tho purpose of the history is to serve as a source of historical information for War Department officials and other authorized individuals. Accordingly, the viewpoint of the writer should be that of General Groves and the reader should be considered as a layman without any specialized knowledge of the subject who may be critical of the Department or the project.

Which is remarkably blunt: write as if Groves himself was saying these things (because someday he might!), and write as if the reader is someone looking for something to criticize. Later the guide gives some specific examples on how to spin problematic things, like the chafing effect of secrecy:

For example, the rigid security restrictions of the project in many cases necessitated the adoption of unusual measures in the attainment of a local objective but the maintenance of security has been recognized throughout as an absolute necessity. Consequently, instead of a statement such as, “This work was impeded by the rigid security regulations of the District,” a statement such as, “The necessity of guarding the security of the project required that operations be carried on in — etc.” would be more accurate.1

This was the history that Groves grabbed whenever he did get hauled in front of Congress in the postwar (which happened less than he had feared, but it still happened). This was the history that the Atomic Energy Commission relied upon whenever it needed to find out what its predecessor agencies had done. It was a useful document to have around, because it contains all manner of statistics, technical details, legal details, and references to other documents in the archive.

"Dante's Inferno: A Pocket Mural" by Louis C. Anderson, a rather wonderful and odd drawing of the Calutron process. From Manhattan District History, Book 5, "Electromagnetic Project," Volume 6.

“Dante’s Inferno: A Pocket Mural” by Louis C. Anderson, a rather wonderful and odd drawing of the Calutron process. From Manhattan District History, Book 5, “Electromagnetic Project,” Volume 6.

The Manhattan District History became partially available to the general public in 1977, when a partial version of it was made available on microfilm through the National Archives and University Publications of America as Manhattan Project: Official History and Documents. The Center for Research Libraries has a digital version that you can download if you are part of a university that is affiliated with them (though its quality is sometimes unreadable), and I’ve had a digital copy for a long time now as a result.2 The 1977 microfilm version was missing several important volumes, however, including the entire book on the gaseous diffusion project, a volume on the acquisition of uranium ore, and many technical volumes and chapters about the work done at Los Alamos. All of this was listed as “Restricted” in the guide that accompanied the 1977 version.3

I was talking with Bill Burr of the National Security Archive sometime in early 2013 and it occurred to me that it might be possible to file a Freedom of Information Act request for the rest of these volumes, and that this might be something that his archive would want to do. I helped him put together a request for the missing volumes, which he filed. The Department of Energy got back pretty promptly, telling Bill that they were already beginning to declassify these chapters and would eventually put them online.

Manhattan Project uranium production flow diagram, from book 7, "Feed materials."

Manhattan Project uranium production flow diagram, from Manhattan District History, Book 7, “Feed materials.”

The DOE started to release them in chunks in the summer of 2013, and got the last files up this most recent summer. You can download each of the chapters individually on their website, but their file names are such that they won’t automatically sort in a sensible way in your file system, and they are not full-text searchable. The newly-released files have their issues — a healthy dose of redaction (and one wonders how valuable that still is, all these years — and proliferations — later), and some of the images have been run through a processor that has made them extremely muddy to the point of illegibility (lots of JPEG artifacts). But don’t get me started on that. (The number of corrupted PDFs on the NNSA’s FOIA website is pretty ridiculous for an agency that manages nuclear weapons.) Still, it’s much better than the microfilm, if only because it is rapidly accessible.

But you don’t need to do that. I’ve downloaded them all, run them through a OCR program so they are searchable, and gave them sortable filenames. Why? Because I want people — you — to be able to use these (and I do not trust the government to keep this kind of thing online). They’ve still got loads of deletions, especially in the Los Alamos and diffusion sections, and the pro-Groves bent to things is so heavy-handed it’s hilarious at times. And they are not all necessarily accurate, of course. I have found versions of chapters that were heavily marked up by someone who was close to the matter, who thought there were lots of errors. In the volumes I’ve gone the closest over in my own research (e.g. the “Patents” volume), I definitely found some places that I thought they got it a little wrong. But all of this aside, they are incredibly valuable, important volumes nonetheless, and I keep finding all sorts of unexpected gems in them.

You can download all of the 79 PDF files in one big ZIP archive on Archive.org. WARNING: the ZIP file is 760MB or so. You can also download the individual files below, if you don’t want them all at once.

Statistics on the ages of Los Alamos employees, from Ted Hall (19) to Niels Bohr (59). From Manhattan District History, Book 8.

Statistics on the ages of Los Alamos employees, May 1945, from the young spy, Ted Hall (19), to the old master, Niels Bohr (59). From Manhattan District History, Book 8.

What kinds of gems are hidden in these files? Among other things:

And a lot more. As you can see, I’ve drawn on this history before for blog and Twitter posts — I look through it all the time, because it offers such an interesting view into the Manhattan Project, and one that cuts through a lot of our standard narratives about how it worked. There are books and books worth of fodder in here, spread among some tens of thousands of pages. Who knows what might be hidden in there? Let’s shake things up a bit, and find something strange.


Below is the full file listing, with links to my OCR’d copies, hosted on Archive.org. Again, you can download all of them in one big ZIP file by clicking here, (760 MB) or pick them individually from below. Items marked with an asterisk are, as far as know, wholly new — the others have been available on microfilm in one form or another since 1977. Read the full post »

Notes
  1. E.H. Marsden, “Manhattan District History Preparation Guide,” (1 August 1945), copy in the Nuclear Testing Archive, Las Vegas, Nevada, accession number NV0727839. []
  2. In fact, I used portions of it — gasp! — on actual microfilm very early on my grad school career, when you still had to do that sort of thing. The volume on the patenting program was extremely useful when I wrote on Manhattan Project patent policies. []
  3. Some of the Los Alamos chapters were later published in redacted form as Project Y: The Los Alamos Story, in 1983. []
Meditations

A bomb without Einstein?

Friday, June 27th, 2014

If Albert Einstein had never been born, would it have changed when nuclear weapons were first produced? For whatever reason, I’ve seen this question being asked repeatedly on Internet forums, as odd as it is. It’s kind of a silly question. You can’t go in and tweak one variable in the past and then think you could know what the outcome would be. History is a chaotic system; start removing variables, who knows what would happen. Much less a variable named Albert Einstein, one of the most influential physicists of the 20th century, and whose importance extended well past the equations he wrote… and those were pretty important equations, at that!

1946 - Einstein Time magazine - detail

Einstein’s 1946 cover of Time magazine. The mushroom cloud is a beautifully executed combination of the Trinity and Nagasaki mushroom clouds.

On the other hand, this kind of science-fiction counterfactual can have its usefulness as a thought experiment. It isn’t history, but it can be used to illustrate some important aspects about the early history of the atomic bomb that a lot of people don’t know, and to undo a little bit of the “great man” obsession with bomb history. Albert Einstein has been associated with the bomb both through his famous mass-energy equivalence calculation (E=mc²) and because of the famous Einstein-Szilard letter to Roosevelt in 1939. On the face of it, this gives him quite a primary role, and indeed, he usually shows up pretty quickly at the beginning of most histories of the Manhattan Project. But neither E=mc² nor the Einstein-Szilard letter were as central to the Manhattan Project’s success as people realize — either scientifically or historically.

In terms of the science, E=mc² gets a lion’s share of attention, most perfectly expressed by Einstein’s portrait on the cover of Time magazine in 1946 (above) with his equation emblazoned on a mushroom cloud. A lot of people seem to think that E=mc² played a key role in the development of the bomb, that the weapon just falls out of the physics. This is wrong. The equation can help one understand why atomic bombs work, but it doesn’t really tell you how they work, or whether you would expect them to even be possible.

The way I like to put it is this: E=mc² tells you about as much about an atomic bomb as Newton’s laws do about ballistic missiles. At some very “low level” the physics is crucial to making sense of the technology, but the technology does not just “fall out” of the physics in any straightforward way, and neither of those equations tell you whether the technology is possible. E=mc² tells you that on some very deep level, energy and mass are equivalent, and the amount of energy that mass is equivalent is gigantic. But it says nothing about the mechanism of converting mass into energy, either whether one exists in the first place, or whether it can be scaled up to industrial or military scales. It gives no hints as to even where to look for such energy releases. After the fact, once you know about nuclear fission and can measure mass defects and things like that, it helps you explain very concisely where the tremendous amounts of energy come from, but it gives you no starting indications.

Eddington's famous plate of the 1919 solar eclipse, which helped confirm Einstein's theory of General Relativity. Very cool looking, and interesting science. But not relevant to atomic bombs. Source.

Eddington’s famous plate of the 1919 solar eclipse, which helped confirm Einstein’s theory of General Relativity. Very cool looking, and interesting science. But not relevant to atomic bombs. Source.

What about the rest of Einstein’s main theoretical work, both Special and General Relativity Theory? They are pretty irrelevant to bomb-making. The physical processes that take place inside atomic bombs are what physicists call “non-relativistic.” Relativity theory generally only shows its hand when you are talking about great speeds (e.g. large fractions of the speed of light) or great masses (e.g. gravitational fields), and neither of those come into play with fission bombs. You can neglect relativity when doing the math to make a bomb.1

An intelligent follow-up question might be: “well, just because relativity theory didn’t play a role in the bomb process itself doesn’t answer the question of whether it started physics on a path that led to the bomb, does it?” Without getting into a long timeline of the “science that led to the bomb,” here, I think we could reasonably summarize the situation like this: Einstein’s 1905 papers (of which E=mc² was one) did indeed play a role in the subsequent developments that followed, but perhaps not as direct a one as people think. E=mc² didn’t inspire physicists to start looking into processes that converted mass to energy — they were already looking into those through an entirely separate (and earlier) line of development, namely the science of radioactivity and particle physics. The fact that huge amounts of energy were released through nuclear reactions, for example, had already been studied closely by the Curies, by Ernest Rutherford, and by Frederick Soddy prior (but only just) to 1905.

Arguably, the most important work Einstein did in this respect was his work on the photoelectric effect (for which he was awarded the Nobel Prize in Physics for 1921), which helped establish the physical reality of Max Planck’s idea of a quantum of energy, which helped kick off investigations into quantum theory in earnest. This had a big influence on the later direction of physics, even if Einstein himself was never quite comfortable with the quantum mechanics that developed in subsequent decades.

The Hahn-Meitner-Strassman experiment apparatus, at the Deutsches Museum in Munich. My own photo.

The Hahn-Meitner-Strassman experiment apparatus, at the Deutsches Museum in Munich. My own photo.

Did any of the relativity work lead, though, down the path that eventually arrived at the discovery of fission in 1939? I don’t think so. The experiments that Hahn, Meitner, and Strassman were doing in Berlin that lead to the discovery of fission in uranium were themselves careful replications of work that Fermi had done around 1934. Fermi’s work came directly out of an experimentalist, nuclear physics context where physicists were bombarding substances with all manner of subatomic particles to see what happened. It was most directly influenced by the discovery of the neutron as a new sub-atomic particle by Chadwick in 1932. This came out of work on atomic theory and atomic modeling that was being done by Rutherford and his students from the early 1910s-1920s. And this early nuclear physics came, most directly, out of the aforementioned context of radioactivity and experimental physics of the late 19th century.

None of which has a strong, direct connection to or from Einstein’s work in my mind. They have some overlaps of interest (e.g. Bohr was a student of Rutherford’s), but the communities working on these sorts of experimental problems are not quite the same as the more theoretical circle that Einstein himself worked in.2 If we somehow, magically, removed Einstein’s early work from the equation here, does the output change much? There would be some reshuffling, probably, but I sort of think that Rutherford would still be doing his thing anyway, and from that much of the other work that led to the bomb would eventually come out, even if it had a somewhat different flavor or slightly different timeline.

My least favorite way of depicting the fission process, where energy (E) is a magic lightning bolt coming out of the splitting atom. In reality, most of the energy comes in the form of the two fission products (F.P. here) repelling from each other with great violence. Source.

This is my least-favorite way of depicting the fission process, where energy (E) is a magic lightning bolt coming out of the splitting atom. In reality, most of the energy comes in the form of the two fission products (F.P. here) repelling from each other with great violence. Source.

Do you even need to know that E=mc² to make an atomic bomb? Perhaps surprisingly, you don’t! There are other, more physically intuitive ways to calculate (or measure) the energy release from a fission reaction. If you treat the fission process as being simply based on the electrostatic repulsion of two fission products, you get essentially the same energy output in the form of kinetic energy. This is how the physics of fission is often taught in actual physics classes, because it gives you a more concrete indication of how that energy is getting released (whereas E=mc² with the mass-defect makes it seem like a magical lightning bolt carries it away). There are other more subtle physical questions involved in making a bomb, some of which have Einstein’s influence on them in one way or another (e.g. Bose–Einstein statistics). But I think it is not totally crazy to say that even if you somehow imagine a world in which Einstein had never existed, that the physics of an atomic bomb would still work out fine — Einstein’s specific technical work wasn’t central to the problem at all. We also have not brought up the question of whether without Einstein, relativity in some form would have been discovered anyway. The answer is probably “yes,” as there were people working on similar problems in the same areas of physics, and once people started paying a close attention to the physics of radioactivity they were bound to stumble upon the mass-energy relationship anyway. This isn’t to denigrate or underestimate Einstein’s influence on physics, of course. What makes Einstein “Einstein” is that he, a single person, pulled off a great number of theoretical coups all at once. But if he hadn’t done that, there’s no reason to think that other people wouldn’t have come up with his theoretical insights individually, if slightly later.

A postwar re-creation of the genesis of the Einstein-Szilard letter.

A postwar re-creation of the genesis of the Einstein-Szilard letter.

What about Einstein’s most direct role, the famous Einstein-Szilard letter of 1939 that influenced President Roosevelt to set up the first Uranium Committee? This is a tricky historical question that could have (and may at some point) an entirely separate blog post relating to it. Its writing, contents, and influence are more complex than the standard “he wrote a letter, FDR created the Manhattan Project” understanding of it that gets boiled down in some popular accounts. My feeling about it, ultimately, is this: if the Einstein-Szilard letter hadn’t been written, it isn’t clear that anything would be terribly different in the outcome in terms of making the bomb. Something like the Uranium Committee might have been started up anyway (contrary to popular understanding, the letter was not the first time Roosevelt had been told about the possibility of nuclear fission), and even if it hadn’t, it isn’t clear that the Uranium Committee was necessary to end up with a Manhattan Project. The road from a fission program whose primary output was reports and a fission program whose primary output was atomic bombs was not a direct one. By early 1941, the Uranium Committee had failed to convince scientist-administrators that atomic bombs were worth trying to build. They had concluded that while atomic bombs were theoretically feasible, they were not likely to be built anytime soon. Had things stayed there, it seems unlikely the United States would have built a bomb ready to use by July/August 1945.

The “push” came from an external source: the British program. Their MAUD Committee (an equivalent of the Uranium Committee) had concluded that a nuclear weapon would be much easier to build than the United States had concluded, and sent an emissary (Mark Oliphant) to the United States to make sure this conclusion was understood. They caught Vannevar Bush’s ear in late 1941, and he (along with Ernest Lawrence, Arthur Compton, and others) wrested control of the uranium work out of the hands of the Uranium Committee, accelerated the work, and morphed it into the S-1 Committee. The name change is significant — it is one of the more vivid demonstrations of the increased degree of seriousness with which the work was taken, and the secrecy that came with it. By late 1942, the wheels for the full Manhattan Project were set into motion, and the work had become a real bomb-making program.

Einstein wasn’t involved with any of the later work that actually led to the bomb. He almost was, though: in late 1941, Bush considered consulting Einstein for help on the diffusion problem, but opted not to push for it — both because Einstein wasn’t regarded as politically reliable (he had a fat FBI file), and his approach to physics just wasn’t very right for practical problems.3 Bush decided that Einstein would stay out of the loop.

Usual, rare anti-Nazi propaganda postcard from 1934, showing Hitler expelling Einstein from Germany, titled "The Ignominy of the 20th Century." It is one of the most blatant visual renderings of Einstein as a "scientific saint." Source.

Unusual, rare anti-Nazi propaganda postcard from 1934, showing Hitler expelling Einstein from Germany, titled “The Ignominy of the 20th Century.” It is one of the most blatant visual renderings of Einstein as a “scientific saint.” Source.

Let’s sum it up. Did Einstein play a role in the creation of the atomic bomb? Of course — his physics isn’t irrelevant, and his letter to Roosevelt did start one phase of the work. But both of these things are less prominent than the Time-magazine-cover-understanding makes them out to be. They weren’t central to what became the Manhattan Project, and if you could somehow, magically, remove Einstein from the equation, it isn’t at all clear that the atomic bomb wouldn’t have been built around the time it actually was built. I don’t think you can really credit, or blame, Einstein for the atomic bomb, in any direct fashion. Einstein did play a role in things, but that role wasn’t as crucial, central, or direct as a lot of people imagine. If you could magically drop him out of history, I think very little in terms of atomic bombs would have been affected.

So why does the Einstein and the bomb myth persist? Why does everybody learn about the Einstein letter, if it wasn’t really was sparked the Manhattan Project? There are two answers here, I think. One is that Einstein was, even before the war, one of the best-known, best-recognized physicists of the 20th century, and was synonymous with revolutionary science and genius. Having him “predict” the atomic bomb with equations in 1905 — 40 years before one was set off — is the kind of “genius-story” that people love, even if it obscures more than it enlightens. It also has a high irony quotient, since Einstein was forced to flee from Germany when the Nazis took power.

But there’s another, perhaps more problematic aspect. In many early copies of the Smyth Report that were distributed by the government, copies of the Einstein letter were mimeographed and loosely inserted. The magnification of Einstein’s role was purposefully encouraged by the government in the immediate period after using the weapon. (And it was even a convenient myth for Einstein, as it magnified his own importance and thus potential influence.) Hanging the atomic bomb on Einstein’s head was an act of self-justification, of sorts. Einstein was the world’s greatest genius in the eyes of the public, and he was a well-known pacifist, practically a scientific saint. After all, if Einstein thought building a bomb was necessary, who could argue with him?

Notes
  1. As Robert Serber puts it: “Somehow the popular notion took hold long ago that Einstein’s theory of relativity, in particular his famous equation E = mc², plays some essential role in the theory of fission. Albert Einstein had a part in alerting the United States government to the possibility of building an atomic bomb, but his theory of relativity is not required in discussing fission. The theory of fission is what physicists call a non-relativistic theory, meaning that relativistic effects are too small to affect the dynamics of the fission process significantly.” Robert Serber, The Los Alamos Primer: The First Lectures on How to Build an Atomic Bomb (University of California Press, 1992), 7. []
  2. For a good, non-teleological, non-bomb-centric approach to the context of 19th- and 20th-century physics, Helge Kragh’s Quantum Generations: A History of Physics in the Twentieth Century (Princeton University Press, 2002), is excellent. []
  3. Einstein wasn’t entirely a head-in-the-clouds physicist, of course. He worked at the patent office, and as Peter Galison has written about, even his famous thought experiments were often motivated by experience with practical problems of time synchronization. And he did help invent a refrigerator with Leo Szilard. But his work on diffusion physics was too abstract, too focused on first-principle analysis, for use in producing a practical outcome. []
Meditations

Feynman and the Bomb

Friday, June 6th, 2014

Richard Feynman is one of the best-known physicists of the 20th century. Most of those who know about him know he was at Los Alamos during the Manhattan Project — some of the best “Feynman stories” were set there. But Feynman’s own stories about his wartime hijinks were, like most of his stories about himself, half just-for-laughs and half lookit-mee! Feynman’s always got to either be a lucky average Joe, or the one brilliant mind in a sea of normals. His Los Alamos antics are mostly just tales of a genius man-child running around a secret laboratory, picking safes and irritating security guards. They aren’t very good gauges of what he actually did towards making the bomb. So what did Feynman actually do with regards to making the bomb? And does it matter, for thinking about his later career, especially the work that won him a Nobel Prize two decades later? 

Los Alamos colloquium from 1946, featuring (foreground, from left-to-right), Norris Bradbury, J. Robert Oppenheimer, John Manley, Richard Feynman, and Enrico Fermi. This version is cropped from the scanned copy at the Emilio Segrè Visual Archives. I will note that unlike the more common copies of this photo that have circulated, you can actually get a sense for how many other people were in the room — it looks like a really packed house.

Los Alamos colloquium from 1946, featuring (foreground, from left-to-right), Norris Bradbury, J. Robert Oppenheimer, John Manley, Richard Feynman, and Enrico Fermi. This version is cropped from the scanned copy at the Emilio Segrè Visual Archives. I will note that unlike the more common copies of this photo that have circulated, you can actually get a sense for how many other people were in the room — it looks like a really packed house.

Feynman’s own stories of his wartime work are centered around things other than the work itself. So he describes doing calculations, but doesn’t really say what they were for. He describes going to Oak Ridge, but only as a pretext for a story about dealing with generals and engineers. He describes the Trinity test, but a lot of that is about his claim to being the only person who saw it without welding glass on. And so on. These give glimpses, but not a very complete picture.

The historian of physics (and my advisor) Peter Galison wrote an article on “Feynman’s War” several years back, looking closely at what it actually was that Feynman was doing at the lab, and how it played into the style that he later became famous for in physics.1 Galison argues that Feynman’s postwar work is uniquely characterized by being “modular, pictorial, and proudly unmathematical.” He contrasts this with the work of several of his contemporaries, including Julian Schwinger, who came up with equivalent solutions to the same physical problems but through a very different (much more mathematical) approach. Feynman’s famous diagrams, which had a huge influence on the teaching and practice of postwar physics, exemplify this approach. What in Schwinger and Tomonaga’s hands (the other people Feynman shared his Nobel Prize with in 1965) was solvable only through massive, lengthy, laborious math could, in Feynman’s hands, be solved through a series of clever diagrams which came up with equivalent results. Feynman’s solutions to quantum electrodynamics weren’t the only way to do it — but they were easier to comprehend, to teach, and to apply to new questions.

The first Feynman diagram, published in R. P. Feynman, "Space—Time Approach to Quantum Electrodynamics,"Physical Review 76 (1949), 769-789, on 772.

The first published Feynman diagram, from Richard P. Feynman, “Space-Time Approach to Quantum Electrodynamics,”Physical Review 76 (1949), 769-789, on 772.

OK, so what does this have to do World War II? Well, Galison’s argument is that you can see the same sort of thinking at work in what Feynman did at Los Alamos, and he argues that it is during the war that he really started applying this mode of physics. He divides Feynman’s work into several “projects.” They were:

  • Neutron measurements for determining critical mass (including the famous “tickling the dragon’s tail” experiment” involving creating brief, barely-subcritical masses)
  • Work on the “Water Boiler” reactor at Los Alamos, which provided further data on nuclear chain reactions
  • Work as a safety supervisor at Oak Ridge, Tennessee, at Oppenheimer’s request (which in his own writings is distilled down to a single humorous anecdote where Feynman is simultaneously clueless and brilliant)
  • Developing formulae relating to criticality and implosion efficiency (including the Bethe-Feynman formula)
  • His work on the hydride bomb, an abortive, Teller-inspired approach to make a “cheaper” fission weapon which involved devilishly difficult calculation (because not all of the neutrons produced in the weapon would be of the same energy)

Galison argues that in each of these instances, you can see the germs of his later approaches. He credits this to both Feynman’s own personal scientific style and inclinations as a theorist (Feynman didn’t seem to like to work with fundamental equations, but with “shortcuts” that lead to quicker, more efficient solutions, for example), but also to the requirements of the wartime goal, where theorists had to come up with tangible, practical results in a very short amount of time.  For example, Galison notes that the formulae relating to how the implosion bomb worked “brought the abstract differential equations to the bottom line: how hot, how fast, how much yield?” The practical needs of the war favored a particular “theoretical style” in general, Galison argues, one that could be most easily meshed with engineering concerns, rapid prototyping, and the lack of time to ruminate on fundamental physics questions.2

The "Water Boiler" reactor at Los Alamos. Source: Los Alamos Archives (12784), via Galison 1998.

The “Water Boiler” reactor at Los Alamos that Feynman worked on. Source: Los Alamos Archives (12784), via Galison 1998, p. 404.

Galison’s article is fairly technical. He goes through Feynman’s work (what of it that is declassified, anyway) and tries to follow his thinking in a very “internal” way, and then match that up with the requirements imposed by the specific wartime context. If you are well-versed in physics you will probably find the details interesting. I’m more of a big-picture person myself, and I like the structure of Galison’s argument even if I don’t feel fully capable of digesting all of the physics involved. One small example of Galison’s work can probably suffice. Feynman was sent to Oak Ridge, as noted, to serve as a safety supervisor. He was taking over for Robert Christy, who got pneumonia in April 1944. The safety question was not a general one, but a very specific one: how many barrels of uranium (in various degrees of enrichment) could be safely stored in a room without running a risk of a criticality accident? Feynman himself relates the problem like this in his famous bit, “Los Alamos from Below” (reproduced in Surely You’re Joking, Mr. Feynman):

It turned out that the army had realized how much stuff we needed to make a bomb — twenty kilograms or whatever it was — and they realized that this much material, purified, would never be in the plant, so there was no danger. But they did not know that the neutrons were enormously more effective when they are slowed down in water. In water it takes less than a tenth — no, a hundredth — as much material to make a reaction that makes radioactivity. It kills people around and so on. It was very dangerous, and they had not paid any attention to the safety at all.

In Feynman’s account, he more or less walks in and figures out what the problems were and how to fix them. The story is about ignorance — in particular systemic ignorance due to secrecy — and Feynman’s attempts to cut through it.

Feynman's diagrammatic sketch of storage of barrels of uranium at Oak Ridge, prepared for his "Safety Report." Source: Galison 1998, p. 408.

Feynman’s diagrammatic sketch of storage of barrels of uranium at Oak Ridge, prepared for his “Safety Report.” Source: Galison 1998, p. 408.

Galison’s account is more technical. Feynman told them that pretty much any amount of unenriched uranium could be stored safely in the facility, but that 5% enriched and 50% enriched had to be handled fairly carefully. 50% enriched uranium in water, for example, would dangerous at a mere 350 grams of material unless there was a neutron absorbing material (cadmium) present. Feynman developed a series of safety recommendations for all grades of enrichments, and had to use reasonable safety margins to make up for potential errors in the calculations. He became the “point man” for safety questions involving fissionable materials, and developed (as Galison puts it) “visualizable” methods for answering basic (but important) questions about hypothetical systems (e.g. for “Gunk storage tanks,” whether they had to be coated with cadmium or not). His methods, Feynman himself emphasizes, were “only approximate, as accuracy has been sacrificed to speed and simplicity in calculation” — the kind of computational “short cut” that was both needed for the practical requirements, but also was common to Feynman’s general approach to physics. Galison concludes the section thus:

The admixture of approximation methods, neutron diffusion, nuclear cross sections, floods, fires and wooden walls marked Feynman’s correspondence with the Oak Ridge engineers. From April of 1944 to September 1945, whatever else Feynman was doing, he was also deeply enmeshed in the barely-existing field of nuclear engineering. Out of this interaction came characteristic rules and modular reasoning: visualizable, approximate, from-the-ground-up calculations applied to neutrons, pans, sheds and sludge. Visionary statements reinterpreting established laws of physics ceded to the exigencies of living in a world he had to reach outside the home culture of theoretical physics as he knew it before the war. Now a billion dollar plant was churning out U-235, and only a calculation stood between thousands of workers and nuclear disaster.

Which is a lot more serious-sounding that Feynman’s own somewhat jokey accounts of the work. In the latter part of the article, Galison connects all of these methods for thinking — and sometimes even the specific problems — with Feynman’s postwar work, showing the influence of his time at Los Alamos.

Diagram of neutron fluctuations from a report by F. de Hoffmann, R.P. Feynman, and R. Serber. Galison notes: "Significantly, Feynman and his collaborators captured the situation in a spacetime diagram drawn with time in the vertical direction and space horizontal. Such an image must be kept in mind when viewing Feynman's early postwar spacetime 'Feynman diagrams,' where again particles are absorbed, emit other particles, and scatter as reckoned by a concatenation of independent algebraic rules." Galison 1998, 405-406.

Diagram of neutron fluctuations from a report by F. de Hoffmann, R.P. Feynman, and R. Serber. Galison notes: “Significantly, Feynman and his collaborators captured the situation in a spacetime diagram drawn with time in the vertical direction and space horizontal. Such an image must be kept in mind when viewing Feynman’s early postwar spacetime ‘Feynman diagrams,’ where again particles are absorbed, emit other particles, and scatter as reckoned by a concatenation of independent algebraic rules.” Galison 1998, 405-406.

Feynman stayed at Los Alamos until the fall of 1946, when he relocated to Cornell University. He never worked on weapons again, but he never took a particularly strong stand on it. What did Feynman think about nuclear weapons, and his role in making them? There is some evidence in his private correspondence, much of which was published not too long ago,3 but it is scant. Most of his responses to inquiries were along the lines of “we feared the Nazis would get one first.”4That’s it. No comment on their use at all, or the end of the war, or any of the other common responses from Los Alamos veterans. When asked in the 1970s about his thoughts on nuclear weapons in general, he demurred: “Problems about the atomic bomb and the future are much more complicated and I cannot make any short  statement to summarize my beliefs here.”5

Feynman gave an interview in 1959 where he was asked directly about the bomb. His response was a little lengthier then, but still said very little:

Now, with regard to our own things as human beings, naturally—I myself, for example—worked on the bomb during the war. Now how do I feel about that? I have a philosophy that it doesn’t do any good to go and make regrets about what you did before but to try to remember how you made the decision at the time. …if the scientists in Germany could have developed this thing, then we would be helpless, and I think it would be the end of the civilization at that time. I don’t know how long the civilization is going to last anyway. So the main reason why I did work on it at the time was because I was afraid that the Germans would do it first, and I felt a responsibility to society to develop this thing to maintain our position in the war.6

This, of course, ignores the question of “so why did you continue when the Germans were known not to have made much progress?” and much more.

Charles Critchfield, Richard Feynman, J. Robert Oppenheimer, and an unidentified scientist, at Los Alamos. Source: Emilio Segrè Visual Archives, via Los Alamos.

Charles Critchfield, Richard Feynman, J. Robert Oppenheimer, and an unidentified scientist, at Los Alamos. Source: Emilio Segrè Visual Archives, via Los Alamos.

During the interview, Feynman was asked, point blank, whether he worked on any secret projects. Feynman said no, and that this was “out of choice.” Pushed further, he elaborated:

I don’t want to [do secret work] because I want to do scientific research—that is, to find out more about how the world works. And that is not secret; that work is not secret. There’s no secrecy associated with it. The things that are secret are engineering developments which I am not so interested in, except when the pressure of war, or something else like that, makes me work on it. … Yes, I am definitely anti-working in secret projects. … I don’t think things should be secret, the people developing this. It seems to me very difficult for citizens to make a decision as to what’s going on when you can’t say what you’re doing. And the whole idea of democracy, it seems to me, was that the public, where the power is supposed to lie, should be informed. And when there’s secrecy, it’s not informed. Now, that’s a naive point of view, because if there weren’t secrecy, there’d be the Russians who would find out about it. On the other hand, there’s some awfully funny things that are secret. It becomes secret that we know what the Russians are keeping secret from us, for instance, or something like that. It seems to me that things go too far in the secrecy.7

After that point in the interview, he steered away from political opinions, explaining that he had strong ones, but he didn’t think they were any more valuable than anyone else’s opinions.

There were those, of course, who did try to recruit Feynman for military work. John Wheeler, his doctoral advisor at Princeton, and the man who had roped him into Los Alamos in the first place, appealed to him strongly to join the Princeton work on the hydrogen bomb (Matterhorn) in late March 1951. Wheeler had heard the Feynman was trying to spend his sabbatical in Brazil, but Wheeler thought the chance of global war was “at least 40%,” and that Feynman’s talents might be better spent helping the country. It was a long, emotional letter, albeit a variation on one that Wheeler sent to many other scientists as well. Wheeler tried to win him (and others) with flattery as well, telling Feynman that “You would make percentage-wise more difference there than anywhere else in the national picture.” In response to Wheeler’s long, many-pointed letter, Feynman simply responded that he didn’t want to make any commitments until he found out whether the Brazil idea would work out. End of story. Nothing specific about the hydrogen bomb one way or the other.

High resolution detail of Feynman's Los Alamos security badge photograph. A this resolution you can see a lot more strain on his face than the one I posted awhile back. Source: Los Alamos National Laboratory Archives.

High-resolution detail of Feynman’s Los Alamos security badge photograph. At this resolution you can see potentially more strain on his face than the one I posted awhile back. Source: Los Alamos National Laboratory Archives.

What should we make of this? Feynman is a complicated man. Much more complicated than the zany stories let on — and I suspect the stories themselves were some kind of defense mechanism. As Feynman’s friend Murray Gell-Mann said at Feynman’s memorial service, Feynman “surrounded himself with a cloud of myth, and he spent a great deal of time and energy generating anecdotes about himself.” They were stories “in which he had to come out, if possible, looking smarter than anyone else.”8 He was not a moralizer, though. His work on the bomb fit into his stories only as a context. He no doubt drew many lessons from his work on nuclear weapons, and he no doubt had many opinions about them in the Cold War, but he kept them, it seems, much to himself.

Oppenheimer famously said that, “In some sort of crude sense, which no vulgarity, no humor, no overstatement can quite extinguish, the physicists have known sin…” Perhaps Feynman agreed — perhaps no more humor could be wrung out of the bomb after Hiroshima and Nagasaki. Maybe it’s harder to write a zany story about the hydrogen bomb. And maybe he was just truly not interested in them from a technical standpoint, or, as he said in 1959, just didn’t think his opinions on these matters, one way or another, were worth a damn, going against the notion held by many of his contemporaries that those who made the bomb had a special knowledge and a special responsibility. To me, he’s still something of an enigma, just one that wrapped himself in jokes, rather than riddles.

Notes
  1. Peter Galison, “Feynman’s War: Modelling Weapons, Modelling Nature,” Stud. Hist. Phil. Mod. Phys. 29, No. 3 (1998), 391-434. []
  2. This is an argument that Galison also makes at length about wartime work in his 1997 book Image and Logic: A Material Culture of Microphysics, both for Los Alamos and for the MIT Rad Lab, which if you’re interested in this kind of thing, is a must-read. []
  3. Michelle Feynman, ed., Perfectly Reasonable Deviations from the Beaten Track: The Letters of Richard P. Feynman (Basic Books, 2005). []
  4. See e.g., Ibid., 268: “I did work on the atomic bomb. My major reason was concern that the Nazi’s would make it first and conquer the world.” []
  5. Ibid., 305. []
  6. Ibid., 421. []
  7. Ibid., 422-423. []
  8. James Gleick, Genius: The Life and Science of Richard Feynman (Pantheon, 1992), on 11. []
Visions

Oppenheimer and the Gita

Friday, May 23rd, 2014

What was going through J. Robert Oppenheimer’s head when he saw the great fireball of the Trinity test looming above him? According to his brother, Frank, he only said, “it worked.” But most people know a more poetic account, one in which Oppenheimer says (or at least thinks) the following famous lines:

I remembered the line from the Hindu scripture, the Bhagavad-Gita; Vishnu is trying to persuade the Prince that he should do his duty and, to impress him, takes on his multi-armed form and says, “Now I am become Death, the destroyer of worlds.” I suppose we all thought that, one way or another.

This particular version, with a haggard Oppenheimer, was originally filmed for NBC’s 1965 The Decision to Drop the Bomb. I first saw it in Jon Else’s The Day After Trinity (1980), and thanks to YouTube it is now available pretty much anywhere at any time. There are other versions of the quote around — “shatter of worlds” is a common variant — though it did not begin to circulate as part of Los Alamos lore until the late 1940s and especially the 1950s.

It’s a chilling delivery and an evocative quote. The problem is that most of the time when it is invoked, it is done purely for its evocativeness and without any understanding as to what it actually supposed to mean. That’s what I want to talk about: what was Oppenheimer trying to say, presuming he was not just trying to be gnomic? What was he actually alluding to in the Gita?

An Indian greeting card for Diwali from 1998, celebrating India's nuclear tests. Source.

An Indian greeting card for Diwali from 1998, celebrating India’s nuclear tests. Source.

I should say first that I’m no scholar of Hindu theology. Fortunately, many years back, James A. Hijiya of the University of Massachusetts Dartmouth wrote a wonderful article on “The Gita of J. Robert Oppenheimer” that covers all of this topic as well as one might ever want it to be covered.1 Everything I know about the Gita comes from Hijiya’s article — so read it if you want much more discussion of this than I have here. I am particularly fond of Hijiya’s opening line, that Oppenheimer’s paraphrase of the Gita is “one of the most-cited and least-interpreted quotations” of the atomic age.

Oppenheimer was not a Hindu. He was not much of anything, religiously — he was born into a fairly secular Jewish family, embraced the Ethical Culture of Felix Adler, and saw philosophy as more of a boon to his soul than any particular creed. He enjoyed the ideas of the Gita, but he was not religious about it. Hijiya thinks, however, that much can be understood about Oppenheimer’s life through the lens of the Gita as a philosophical and moral code, something necessary in part because Oppenheimer rarely discussed his own internal motivations and feelings about making the bomb. It helps explain, Hijiya argues, that a man who could utter so many public statements about the “sin” and “terror” and “inhumanity” of Hiroshima and Nagasaki could also have been the one who pushed for their use against Japan and who never, ever said that he actually regretted having built the bomb or recommending its use. It helps resolve one of the crucial contradictions, in other words, at the heart of the story of J. Robert Oppenheimer.

J. Robert Oppenheimer, from the Emilio Segrè Visual Archives.

J. Robert Oppenheimer, from the Emilio Segrè Visual Archives.

It’s not clear when Oppenheimer was first exposed to the Gita. I have seen accounts, in oral histories, that suggested that he was spouting Gita lines even while he was a young graduate student studying in Europe. What is definitely known is that he didn’t start studying Sanskrit seriously until 1933, when he started studying with the renown Sanskrit scholar Arthur W. Ryder while he was a professor at Berkeley. In letters, he wrote gushingly about the book to his brother, and much later he quoted from it at the service held at Los Alamos in April 1945 upon the death of President Roosevelt.

The story of the Gita is that of Arjuna, a human prince who has been summoned to a war between princely cousins. Arjuna doesn’t want to fight — not because he lacks courage, or skill, but because it is a war of succession, so his enemies are his own cousins, his friends, his teachers. Arjuna does not want to kill them. He confides in his charioteer, who turns out to be the god Krishna2 in a human form. The text of the Gita is mostly Krishna telling Arjuna why Arjuna must go to war, even if Arjuna does not want to do it.

Krishna’s argument hinges on three points: 1. Arjuna is a soldier, and so it is his job — his duty — to wage war; 2. It is Krishna’s job, not Arjuna’s, to determine Arjuna’s fate; 3. Arjuna must ultimately have faith in Krishna if he is going to preserve his soul.

Arjuna eventually starts to become convinced. He asks Krishna if he will show him his godlike, multi-armed form. Krishna obliges, showing Arjuna an incredible sight:

Krishna revealing himself to Arjuna. Source.

Krishna revealing himself to Arjuna. Source.

A thousand simultaneous suns
     Arising in the sky
Might equal that great radiance,
     With that great glory vie.

Arjuna is awestruck and spellbound:

Amazement entered him; his hair
     Rose up; he bowed his head;
He humbly lifted folded hands,
     And worshipped God. . . .

And then, in his most amazing and terrible form, Krishna tells Arjuna what he, Krishna, is there to do:

Death am I, and my present task
     Destruction.

Arjuna, suitably impressed and humbled, then agrees to join in the battle.

The above quotes are from Ryder’s translation of the Gita. You can see that Oppenheimer’s is not especially different from that, even if it is somewhat changed. Personally I find Ryder’s version of the last part more impressive — it is more poetic, more stark. Ryder’s translation, Hijiya explains, is a somewhat idiosyncratic but defensible one. What Ryder (and Oppenheimer) translate as “Death,” others have translated as “Time,” but Hijiya says that Ryder is not alone for calling attention to the fact that in this context the expanse of time was meant to be a deadly one.

If you would like to see the famous “death” verse in the original, it is chapter 11, verse 32 of the Gita, and looks like this:

Gita verse 11:32

This website (from which I got the above) translates it as:

Lord Krsna said: I am terrible time the destroyer of all beings in all worlds, engaged to destroy all beings in this world; of those heroic soldiers presently situated in the opposing army, even without you none will be spared.

While I find Ryder’s more poignant, the longer translation makes it extremely clear what Krishna has in mind. All will perish, eventually. In war, many will perish whether you participate or not. For Oppenheimer and the bomb, this may have seemed especially true. The cities of Hiroshima and Nagasaki (and others on the target list) were on it not because they were necessarily the most important, but because they had so far been spared from firebombing. They were being actively preserved as atomic bomb targets. Had the bomb not been used or made, they probably would have been firebombed anyway. Even if the physicists had refused to make nuclear weapons, the death toll of World War II would hardly have been altered.

Trinity long exposure

“A thousand simultaneous suns”: a long-exposure shot of the Trinity test.

So let’s step back and ask who Oppenheimer is meant to be in this situation. Oppenheimer is not Krishna/Vishnu, not the terrible god, not the “destroyer of worlds” — he is Arjuna, the human prince! He is the one who didn’t really want to kill his brothers, his fellow people. But he has been enjoined to battle by something bigger than himself — physics, fission, the atomic bomb, World War II, what have you — and only at the moment when it truly reveals its nature, the Trinity test, does he fully see why he, a man who hates war, is compelled to battle. It is the bomb that is here for destruction. Oppenheimer is merely the man who is witnessing it. 

Hijiya argues that Oppenheimer’s sense of Gita-inspired “duty” pervades his life and his government service. I’m not sure I am 100% convinced of that. It seems like a heavyweight philosophical solution to the relatively lightweight problem of a life of inconsistency. But it’s an interesting idea. It is perhaps a useful way to think about why Oppenheimer got involved with so many projects that he, at times, seemed ambivalent about. Though ambivalence seemed readily available in those days — nobody seems to be searching for deep scriptural/philosophical justifications for Kenneth Bainbridge’s less eloquent, but equally ambivalent post-Trinity quote: “Now we’re all sons-of-bitches.”

A rare color photograph of Oppenheimer from October 1945, with General Groves and University of California President Robert Sproul, at the Army-Navy "E" Award ceremony. Source.

A rare color photograph of Oppenheimer from October 1945, with General Groves and University of California President Robert Sproul, at the Army-Navy “E” Award ceremony. Source.

One last issue that I find nagging me. We have no recording of Oppenheimer saying this except the 1965 one above. By this time, Oppenheimer is old, stripped of his security clearance, and dying of throat cancer. It is easy to see the clip as especially chilling in this light, given that is being spoken by a fading man. How would it sound, though, if it was coming from a younger, more chipper Oppenheimer, the one we see in photographs from the immediate postwar period? Would it be able to preserve its gravity?

Either way, I think the actual context of the quote within the Gita is far deeper, far more interesting, than the popular understanding of it. It isn’t a case of the “father” of the bomb declaring himself “death, the destroyer of worlds” in a fit of grandiosity or hubris. Rather, it is him being awed by what is being displayed in front of him, confronted with the spectacle of death itself unveiled in front of him, in the world’s most impressive memento mori, and realizing how little and inconsequential he is as a result. Compelled by something cosmic and terrifying, Oppenheimer then reconciles himself to his duty as a prince of physics, and that duty is war.

Notes
  1. James A. Hijiya, “The Gita of J. Robert Oppenheimer,” Proceedings of the American Philosophical Society 144, no. 2 (June 2000), 123-167. []
  2. Oppenheimer, in his 1965 interview, identifies the god as Vishnu, perhaps in error. Krishna is an avatar of Vishnu, however, so maybe it is technically correct along some line of thinking. []