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Followup To Bohr-Heisenberg Meeting
December writes "As a follow up to this slashdot article, "The family of Niels Bohr has decided to release all documents deposited at the Niels Bohr Archive, either written or dictated by Niels Bohr, pertaining specifically to the meeting between Bohr and Heisenberg in September 1941. There are in all eleven documents. The decision has been made in order to avoid possible misunderstandings regarding the contents of the documents."
See the Niels Bohr Archive at http://www.nba.nbi.dk/"
Why is this such a big deal anyway? Heissenberg, one of many famous modern physisists might have been a Nazi. So was almost the entire german population for crying out loud. Most of them did not know the entire story, and later on most of them understood that they had been horribly wrong. Let it rest.
Try out fish, the friendly interactive shell.
If they knew Seuss, it'd be the Cat in the Hat in the Box - with the Nazi weapons programme... I'm not sure where the eggs and ham fit in though, can anyone clarify?
I've had waay too much coffee...
Bohr thought the sun would continue to rise in the east. Heinsenberg was said to be uncertain.
-pyrrho
An article from yesterday's Washington Post headlined "World War II-era scientist Niels Bohr said he was shocked to learn from colleague Werner Heisenberg that Germany was "vigorously in a race to be the first with atomic weapons," according to a decades-old letter released Wednesday."
If you celebrate Xmas, befriend me (538
I haven't read the letters but there was a program on TV this evening. IANAH but I'm just writing what I heard on that show.
Basically, they said that Heisenberg travelled to his friend Bohr whom he hadn't seen for years. This was in 1941 while the Germans were still going strong. Bohr didn't believe an atomic bomb was possible. Heisenberg was furious that Bohr didn't believe his physics and replied that he had been heading a team for two years. Heisenberg wanted Bohr on the team. Germany will win; be a slave or be a Nazi.
We now know the outcome. Bohr fled to Sweden, and Heisenberg didn't make the bomb. The thing with these letters is that until now people thought Heisenberg deliberately frustrated the German war effort. Which is apparently not the case.
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Warning: Slashdot may contain traces of nuts.
They met in September 1941. I guess that means we can't know where they met.
To separate, process, and manufacture the uranium and plutonium necessary for the A bombs, it required 32% of the US electrical output, 23% of the US Silver output (144,000 Troy Ounces was the figure I believe), and 14% of the US aluminum output to construct the plants (at Oak Ridge, Tennessee and Hartford, Washington). Remember this is 1944 people - height of America's industrial might. Now ask yourself if Germany could've done the same...
What the letters make clear is that Bohr felt very threatened by Heisenburg's visit and that he assumed that Heisenburg would be working to create a Nazi A-bomb.
What will never be known is what Heisenburg's intent actually was. Clearly his post-war statements should be viewed with suspicion, but, to give him the benefit of the doubt, he claimed to have been misunderstood by Bohr because he was afraid that the SS was spying on them, which is certainly a possibility.
I'm not sure where the eggs and ham fit in though, can anyone clarify?
Yes indeedy, I surely can. Thru the slot in the side to feed the cat. Otherwise the cat would die before anyone opened the box. You wouldn't want to make a mockery of the whole physics quantum thang by letting the cat starve while the theorists dithered about with blackboards and chalk, would you?
Infuriate left and right
In 1942, a prototype reactor in Leipzig exploded when heavy water leaked into a uranium shell, shortly before it would have reached criticality. [2]
We're DAMN LUCKY that Heisenberg's efforts ultimately failed.
[1] Blood and Water: Sabotaging Hitler's Bomb (ISBN 0-8050-3206-1), by Dan Kurzman, p.35.
[2] Ibid, p. 38.
Oh, no! You have walked into the slavering fangs of a lurking grue!
Fact #1: Bohr and Heisenberg were there when quantum physics was being born. Both contributed greatly to it's discovery.
Fact #2: The Nazis never had the ability to fight and build a nuke after the astonishing raid against the heavy water plant in Norway. In 1941, they had lost the Battle of Britain, were losing the capability to launch an invasion of Britain, and were focussing a lot of effort on the Battle of the Atlantic.
<interlude >
(which they would have won until American long-range bombers(B29s) became available in large numbers - The courage and acheivements of the British Royal and Merchant navies should not be forgotten, but it was the closing of the Iceland-UK gap by airpower that won the Battle of the Atlantic. Thankyou once again America.)
</interlude >
It's all ancient history. But please give respect to the British-trained Norwegians who perpetrated the astonishing raid that ended Nazi nuclear capabilities.
More information:here
Basically, they landed by parachute in Norway, infiltrated one of the most highly defended places in Nazi-controlled Europe, and set of some charges. The charges were placed next to some fat cables deep in a long tunnel. The cables were carrying enough current (many tens of thousands of amps) that the electromagnetic effects when they shorted blew a kilometer of tunnel to bits.
Another team sank a ship carrying 1000 tons of heavy water from Norway to Germany.
After those losses, the German nuke program didn't have chance.
<googlefailure>>
Google (and AltaVista) have failed to give many useful hits on these events. The people who executed these raids deserve more web presence. Please post links.
</googlefailure>>
If you read "Virus House", later published as "The German Atomic Bomb", you will see that the Nazis (Heisenberg, et al.) were astounded when they heard about Hiroshima and Nagasaki. They really didn't think it could be done. Was that due to Aryan superiority beliefs or due to their science, hard to say.
One story told by my history of science prof (he had interviewed Teller, Groves, Oppy, Szilard, etc.) was that Max Born was given the assignment of calculating the neutron cross section of graphite. This is useful for determining how much the neutrons coming out of a fission would be slowed, so they can hit another nucleus. For a reactor to work, they need to be slowed a little but not absorbed. Hence the need to know the cross-section.
He apparently goofed with the decimal points, and wound up "proving" that graphite would never work. Pretty surprising since they had a small reactor going in Paris shortly after the city fell, moderated by graphite.
That's why the Nazis kept trying to build heavy water plants - they thought that was the only possible reactor medium to use. But heavy water plants are fairly obvious targets, and Allied saboteurs took most of them out.
John 17:20
That may seem like a mundane explanation, given what we now know about Nazi Germany and the power of nuclear bombs. But Heisenberg probably did not know the extent of Nazi atrocities and he also didn't know whether a real A-bomb would fizzle or bang.
It's tempting to see all of WWII in terms of villains and heroes. But most people were probably neither; they were just people trying to get on with their lives under difficult circumstances. Heisenberg could have been a hero or a villain, but he ended up being neither.
No, no, no. Remember, Planc's constant (which defines the size of uncertainty) is in Js. That means that if you know when the meeting happened you can't know how much energy was expended there. The conjugate of position is momentum, so to be uncertain where the meeting took place we'd need to know its mass and velocity.
Come on people, this is very simple physics.
There's no point in questioning authority if you aren't going to listen to the answers.
There is a link here of history of the atomic bomb. Oh, and it includes directions on how one is built as well.
On August 2nd 1939, just before the beginning of World War II, Albert Einstein wrote to then President Franklin D. Roosevelt. Einstein and several other scientists told Roosevelt of efforts in Nazi Germany to purify U-235 with which might in turn be used to build an atomic bomb. It was shortly thereafter that the United States Government began the serious undertaking known only then as the Manhattan Project. Simply put, the Manhattan Project was committed to expedient research and production that would produce a viable atomic bomb.
This and this link describe the Japanese atomic bomb program. Germany sent a submarine to Japan carrying uranium oxide, a needed element in building an a-bomb, but it surrendered after Hitler's defeat and was confiscated by the U.S. This uranium could have been used in the atom bombs dropped on Hiroshima and Nagasaki.
Another good link is here.
There was reason to fear that Germany might win the race to produce the bomb. Fission had been discovered in Germany, and German scientists were at least as able as anyone else to assess its significance. Moreover, it seemed ominous that Germany had stopped the sale of uranium ore from the rich mines in Czechoslovakia. Up until mid-1941, concern over a German bomb had been stronger in Britain than in the United States. About that time, however, the sense of urgency began to pervade U.S. nuclear scientists.
--Metrollica
Suggested reading: Shirer's Rise and Fall of the Third Reich
Hitler never polled a majority in any of the German elections. He at best only managed votes from 39-40 % of the electorate and was awarded the chancellorship unwillingly by an old and tired Hindenburg who was led to believe that this was the only to break the cycle of repeated elections with no clear winner, followed by dissolved governments.
What immediately followed of course is history: The burning of the Reichstag by agents of the Nazis, followed by Hitler's invocation of "emergency powers" to curb what would today be called "terrorism" (sound familiar anyone?). By the time the average German realized what was happening, it was too late and any who were in a position to mount any sort of opposition were either in the camps, dead, or scattered and demoralized.
You're using her as bait, Master!
What most people don't seem to know is that Heisenberg didn't visit Bohr alone. Carl Friedrich von Weizsäcker was also there, and he is still alive today.
He gave an interview with the Süddeutsche Zeitung one or two days ago. His recollection of the meeting is rather interesting (the interview is in German, sorry).
Firstly, he says that Heisenberg started an A-bomb project in 1939, in which Weizsäcker took part, but by 1941 they came to the conclusion that they would not be able to succeed before the war was over. The problem was the tremendous effort needed to separate the isotopes. So from 1941 on they were only interested in building a reactor. Once that worked (it never did, as the heavy water production was sabotaged) there might have been the possibility to create Plutonium and build a bomb with that. But they didn't expect this to happen before the war was over by conventional means.
The reason Heisenberg went to see Bohr, according to Weizsäcker, was that they didn't want the Americans or the British to build a bomb either. If they stated publically that they're not working on a bomb, then of course nobody would have believed them. But Heisenberg thought that they might believe Bohr. So he hoped that Bohr could convince the Allies not to build the bomb either. This was not motivated by pure pacifism - he didn't want Germany to get nuked.
In 1941 the war looked pretty good for Germany, they were winning on all fronts. So basically Heisenberg believed that a German victory was inevitable, but with conventional weapons. He tried to explain this to Bohr, who was shocked. Bohr may have understood Heisenberg's "inevitable" to mean that he WAS working on a bomb, and planning to use it. But Weizsäcker suggests that Bohr may well have understood correctly, and didn't want the Germans to win (conventionally), and therefor figured that the Allies would have to build a bomb, to avoid a Nazi victory.
What we can accept as quite reliable, is the following: (a) Heisenberg did lead an A-bomb project from 1939 to 1941. (b) He came to the conclusion that he couldn't build a bomb before the war was over. (c) He continued working on a reactor from 1941 onwards (possibly with the option of producing Plutonium for later weapons use).
And what also seem quite plausible: (d) that he tried to convince Bohr that he was only working on a reactor, not a bomb. This is what he claimed afterwards, and is backed up by Weizsäcker. Many people might not believe these two, so here is another interesting piece of the puzzle:
I read some time ago, either in Physics Today or in Scientific American that when Bohr came to Los Alamos, he brought with him a sketch which Heisenberg had made during his 1941 visit. Bohr claimed it depicted a bomb which Heisenberg was building, but the people at Los Alamos recognised it as a heavy water reactor. As far as I remember, the sketch depicted a large bottle, filled with water (presumably heavy water, but only labelled "H2O"), and some stuff inside. Can anybody dig up this sketch on the net? At any rate, this strongly suggests that Bohr had misunderstood Heisenberg, and mistook Heisenberg's reactor for a bomb.
"...Look on my works, ye mighty, and despair!"
Than this.. there is more evidence than just the standard: "Bohr's word against Heisenbergs"
For instance, Gitta Serenys excellent
book "Albert Speer: His battle with truth".
(Albert Speer was the Nazi minister of armaments during the latter part of the war).
In the book Sereny notes that Speer, in a letter to a friend from Spandau prison after the war,
wrote of Heisenbergs engagement in developing an A-bomb, and how he had they had been short of funds.
According to the book, Speer remarked in the letter something to the extent of: "Now, I suppose he'll claim he didn't want the bomb built, and didn't ask for funding".
This is, in fact, what Heisenberg claimed after the war. However, Speer could not have known this, since the prisoners in Spandau were not allowed to read newspapers or have any correspondence with the outside world.
(With the exception of the contraband letters)
To me at least, this seems pretty incriminating,
especially together with the testimony of Bohr.
On the other hand, I would be careful to damn Heisenberg:
Just look at how the USA made a 'hero' out of Werner von Braun, a man who not only built missiles, he administrated the cruel and inhumane concentration camps where the missiles were manufactured.
...and spoil it. I'm going to see Copenhagen tommorow.
CUR ALLOC 20195.....5804M
From my reading of the current material, and of other sources:
1. Heisenberg took a substantial risk visiting Copenhagen and discussing secret and dangerous information with Bohr. We don't know exactly what was on his mind, but he wasn't doing this lightly.
2. Heisenberg didn't like his fascist government; but he was still a patriot and wanted to do what was good for his people in the long run.
3. In 1941, it was a very reasonable conclusion that Germany would win the war. Most people feared this. It would not be unreasonable to plan accordingly.
4. Heisenberg was very, very smart.
5. Bohr was troubled by what he saw as inconsistent and inexplicable behavior. He was surprised and concerned, at the time and later, and he sought in vain to understand his friend's words and actions, which seemed clear but inexplicable to him.
6. After the war, Heisenberg felt bitter and misunderstood, and avoided discussing wartime events after having received censure from many sides.
Assume, for the moment, that in 1941 Heisenberg a) thought Germany would win the war, b) hoped Bohr was aware how serious a threat was posed by nuclear weapons, c) wanted to prepare for good humane postwar German physics, and d) deliberately but secretly focused German research efforts on avenues leading to peaceful applications. How would his behavior have been different? Who would have been aware of this lonely struggle, at the time or later? And, assuming this were all true, how bitter and frustrated would he feel after the war, being blackguarded for actions that (if all were known) should be seen as heroic?
The historical record is clearly ambiguous, and there are certainly valid interpretations of events that show him in a bad or foolish light. But this was an extraordinary man, dealing with titanic issues at an extraordinary time. I am more inclined to give him the benefit of the doubt. The great scientists I've known have tended to share a common trait: intellectual honesty, to the point of ruthlessness and even self-destruction if necessary. The great thinker is rarely petty of self-deceptive about important issues. So I have a hard time picturing Heisenberg conducting decades of revisionism to whitewash over bad behavior. I find it more likely that Bohr misunderstood his brief exchange with a troubled and tortured man, a man who was trying to do what he thought was right in a difficult situation. Bohr's own mystification with Heisenberg's actions is clear in the draft letters.
We won't ever have a certain resolution to this question, because letters and recordings only reveal certain kinds of information. The truth was hidden in Heisenberg's inner beliefs and motivations, but he chose to close the door on discussing such issues, after receiving what he perceived as unfair rebukes.
For me, it all comes down to a question of emotional and intellectual plausibility. Which 'plot' makes the most human sense -- Heisenberg as shallow, self-interested, incompetent, venal Nazi bureaucrat? -- or Heisenberg as an heroic, solitary, tortured visionary? Each version of history has problems, but look at the stature and reputation of this man before the war. He was larger than life. I hate to see him made so small in today's debate.
-- We all have enough strength to endure the misfortunes of other people. La Rochefoucauld