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Nazi Germany had no hope of making an atomic bomb, uranium cubes reveal

137 points · 121 comments · xqcgrek2

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JumpCrisscross · 1790911159 · focus · HN ↗
[dead]
1. scun · 1790914048 · focus · HN ↗
  Coincidentally TIL about a Namibian politician who decided to drop the "Hitler" from his name. I only mention it because his first name is also Adolf
  1. [deleted] · 1790963343 · focus · HN ↗
    [deleted]
2. karim79 · 1790922784 · focus · HN ↗
  Don't underestimate the other Hitlers. They might still be around us.
3. moritzwarhier · 1790939094 · focus · HN ↗
  the purpose of square-bracketed text in quotes is to mark editorializing
  1. stackghost · 1790960982 · focus · HN ↗
    I think the point is that in an article about Nazi Germany, editorializing "Hitler" to add "Adolf" is probably not required because almost every adult in the English-speaking world knows who Hitler was.
    SoftTalker · 1790962343 · focus · HN ↗
    The more I learn about that fella, the less I like him.
    1-more · 1790963806 · focus · HN ↗
    You joke, but Destined to Witness is a really interesting memoir of German-Liberian Hans-Jurgen Massaquoi growing up in the rise of Nazi Germany as a young kid and then experiencing WWII as a civilian German teen. I ended up learning how the Nuremberg laws came down on kids at playgrounds, etc., something I'd never considered. Sure it pales in comparison to everything else, but it's always interesting to learn one more way the Nazis were just awful.
  2. happytoexplain · 1790961360 · focus · HN ↗
    That's why it's notable. If it were part of the original quote, it wouldn't be.
    moritzwarhier · 1791043082 · focus · HN ↗
    [delayed]
4. joshblack1982 · 1790961817 · focus · HN ↗
  Not to be confused with Adolf Hitler's half-nephew Bill Hitler, who fought against Adolf Hitler.
expedition32 · 1790925650 · focus · HN ↗
This was already known. The British put the German scientists into a big country house after the war and bugged all the rooms. After the US dropped the atomic bombs the German scientists spent weeks discussing with eachother how the Americans could have done it. They never got it right.
1. amsully · 1790960324 · focus · HN ↗
  It’s a great read from beginning to end <a href="https://germanhistorydocs.org/en/nazi-germany-1933-1945/transcript-of-surreptitiously-taped-conversations-among-german-nuclear-physicists-at-farm-hall-august-6-7-1945" rel="nofollow">https://germanhistorydocs.org/en/nazi-germany-1933-1945/tran...
  1. yalok · 1790962529 · focus · HN ↗
    Amazing. Kind of reminds of the modern day discourse on potential dangers of AGI and humans misuse of it.
    Robotbeat · 1790963455 · focus · HN ↗
    Yup.
    aaroninsf · 1790969003 · focus · HN ↗
    That would be a false similarity in some important ways.
    This was a very specific single technical problem, requiring a silo from basic science to theoretical physics to advanced engineering, etc., with each layer having its own space of failure modes.
    Something like the reverse is true with sufficiently-capable and sufficiently-efficient AI, which we are rapidly evolving to.
    In our current situation, the attack surface is quite literally our entire highly interdependent civilization and its components. AI does not need to be autonomous, it just needs to employed, either will wilful bad intent, or, poorly stated goals, or, poor alignment, or, simple mistakes and errors, to break things.
    The challenge with security is always that the attacker need only succeed once.
    This does not mean doomerism has it right, especially in narratives based on poor understanding or extapolation beyond what is now konwn. The chance of "extinction" in particular is overstated.
    The chance of one or more compounding "Chernobyl scale" gray swan events however is ever increasing.
    Personally I don't think that's remotely contestable.
    As a civilization and society and industry we need to have process, and public process at that, about the nature of the risks faced.
    That process has not yet emerged in any coherent way; a hundred letters have been signed and such but to no actual effect, bar one performative "executive order" this week.
  2. NDlurker · 1790962623 · focus · HN ↗
    That was incredibly interesting. Thank you for sharing.
  3. fierycatnet · 1790963721 · focus · HN ↗
    Nice gem
  4. throwaway219450 · 1790965343 · focus · HN ↗
    Is this the same mansion that the war office put a bunch of high ranking PoWs in? Same idea - butter up the generals, bug the entire building and wait for them to spill secrets (which they did so often, and with such value, that military intelligence ignored Churchill’s request to shut it down).
    <a href="https://www.bbc.com/culture/article/20260811-the-uk-stately-home-where-nazis-were-bugged" rel="nofollow">https://www.bbc.com/culture/article/20260811-the-uk-stately-...
    tempestn · 1790966410 · focus · HN ↗
    Why did Churchill want it shut down?
    throwaway219450 · 1790967481 · focus · HN ↗
    <a href="https://www.bbc.com/news/uk-20698098" rel="nofollow">https://www.bbc.com/news/uk-20698098
    The Beeb has run this a couple of times.
    > Mrs Fry also says Winston Churchill was outraged when he learned the generals had been bussed into the lavish Simpson's-in-the-Strand in central London for lunch. He ordered what he called "the pampering of the generals" to be stopped.
    > But spoiling the generals and boosting their egos was providing so much useful information that the British intelligence officers decided to carry on, and simply stopped telling Churchill about it.
    [deleted] · 1790967553 · focus · HN ↗
    [deleted]
  5. tempestn · 1790966370 · focus · HN ↗
    You should submit that as a post, if you haven't already. Fascinating read.
  6. constantius · 1790977689 · focus · HN ↗
    > HAHN [discovered nuclear fission] was completely shattered by the news and said that he felt personally responsible for the deaths of hundreds of thousands of people, as it was his original discovery which had made the bomb possible. He told me that he had originally contemplated suicide when he realized the terrible potentialities of his discovery and he felt that now these had been realized and he was to blame.
    > HAHN: I must honestly say that I would have sabotaged the war if I had been in a position to do so.
    > VON WEIZSÄCKER again expressed horror at the use of the weapon and HEISENBERG replied that had they produced and dropped such a bomb they would certainly have been executed as War Criminals having made the “most devilish thing imaginable”.
    > WEIZSÄCKER: History will record that the Americans and the English made a bomb, and that at the same time the Germans, under the HITLER regime, produced a workable engine. In other words, the peaceful development of the uranium engine was made in GERMANY under the HITLER regime, whereas the Americans and the English developed this ghastly weapon of war.
    Fascinating. You definitely must post it, I'd enjoy reading a discussion about this, as would others in this thread.
  7. OG_BME · 1790979777 · focus · HN ↗
    Thank you for sharing this!
2. smallmancontrov · 1790961229 · focus · HN ↗
  Heisenberg used a bad approximation that led him to incorrectly believe he would need tons of U235 to produce a bomb. His model for bomb viability was essentially "a random neutron walk should not leave the core until producing enough generations to explode." In reality, you don't need that much U235 because earlier generations have exponentially more descendants and they are closer to the core -- the later generations can leak neutrons out of the core like a sieve and the exponential party deep in the core won't even notice, effortlessly replacing them by cooking a tiny fraction of a generation longer.
  It was Peierls and Frisch, two Jewish German scientists, who figured out those dynamics, modeled them with the Neutron Diffusion equation, and repeatedly prodded UK intelligence until they were taken seriously. Then the project got sent across the Atlantic for safety and scale-up and the rest is history.
  Germany could have had the Atom Bomb in WWII, but Nazi Germany could not have because Jewish Science gave a decisive advantage.
  1. sandworm101 · 1790961479 · focus · HN ↗
    >> Jewish Science
    Jewish Scientists.
    darubedarob · 1790961753 · focus · HN ↗
    [dead]
    smallmancontrov · 1790961846 · focus · HN ↗
    I was mocking the Nazi attacks on the work of Jewish scientists which branded that work as "Jewish Science" and declared it inferior, because this whole story is a Reverse Uno card on that narrative.
    ahartmetz · 1790962468 · focus · HN ↗
    Some part of the German physics community even did "German physics" which did not include quantum physics and relativity.
    gloryjulio · 1790963067 · focus · HN ↗
    Agree with that. There were also 'Soviet Science'.
    eli_gottlieb · 1790963292 · focus · HN ↗
    Yes, but it would have been a better world if the Nazis had never invented the idea of Judenphysik in the first place. It stopped Gentile German physicists from working on whole areas of research!
    atq2119 · 1790963928 · focus · HN ↗
    I'm okay with that if it helped prevent Nazi Germany from building an atom bomb...
  2. darubedarob · 1790961620 · focus · HN ↗
    [dead]
  3. ianburrell · 1790962861 · focus · HN ↗
    Another problem is that Germans went for heavy water reactors and didn't even get as far as prototypes. Americans built graphite moderated reactors and quickly built plutonium production reactors at Hanford. Also, Allies were able to prevent Germans getting heavy water from Norway.
  4. antonvs · 1790964153 · focus · HN ↗
    > Jewish Science gave a decisive advantage.
    It's interesting, and concerning, to see the exact same thinking in the US today.
    The claim was that theoretical, mathematical models of physics, like special relativity, were a product of "Jewish thinking," designed to deliberately confuse the world.
    There's a recent video in which Tucker Carlson interviews Jess Elofson and they mutually agree that algebra is nonsense, with Elofson calling it "fake math". They didn't go so far as to relate it to some ethnic source (from the part I watched), but "designed to deliberately confuse the world" is the big selling point. The people they hate are people smarter than them.
    On the plus side, this is why these anti-intellectual movements always fail, because in the end they just can't get much useful done, other than attacking and destroying which doesn't require finesse or understanding.
    Edit: I have to retract what I wrote about not relating it to an ethnic source. Elofson literally used the term "goy slaves" in that interview.
    RajT88 · 1790965172 · focus · HN ↗
    The word "algebra" comes from Arabic al-jabr - so it's Muslim math to them I guess would be the talking point?
    Tucker Carlson has a backpfeifengesicht.
    xhkkffbf · 1790979690 · focus · HN ↗
    It was invented before Islam began. I believe the creator was Persian.
    RajT88 · 1790995351 · focus · HN ↗
    I took a spin through wikipedia - the roots go well back into pre-Christianity.
    It's pointless to try and make this point with fans of Mr. Carlson. They don't want to know.
    throwawayffffas · 1790967952 · focus · HN ↗
    Wait until Tucker hears about imaginary numbers.
    ludicrousdispla · 1791020100 · focus · HN ↗
    maybe he'd just consider it a hyperbolic statement
    antonvs · 1791039775 · focus · HN ↗
    Even worse, complex numbers!
    belviewreview · 1790983354 · focus · HN ↗
    Fake math? Does he know that all the electric circuits in the equipment that is used to broadcast his program are designed using algebra?
  5. nostrademons · 1790989717 · focus · HN ↗
    It looks like Heisenberg wasn't wrong about the chemistry, only about the economics and willingness of Americans to throw massive amounts of resources at a project:
    > HEISENBERG: I don’t believe a word of the whole thing. They must have spent the whole of their ₤500,000,000 in separating isotopes; and then it’s possible.
    In reality, the Manhattan project cost about $2B, roughly ₤500,000,000 at the exchange rate of the time. And 85% of it went into building the huge isotope-separation plants in Oak Ridge and Hanford. Heisenberg's estimate was just about on the mark; he just didn't understand that America was willing to spend ₤400M building huge factories to do the necessary uranium separation.
    > WIRTZ: We only had one man working on it and they may have had ten thousand.
    In reality, America put 600,000 people to work on it. The Germans were incredulous because they could never get political buy-in for the massive scale mobilization needed to build the bomb. America was willing to spend more and employ more people.
    TitaRusell · 1791102598 · focus · HN ↗
    Germany just wasn't the kind of industrial powerhouse that the US and USSR were. Their whole blitzkrieg strategy was based on the knowledge that they could not win a war of attrition.
3. gib444 · 1790963806 · focus · HN ↗
  I'm trying to reconcile such wildly clever people not wondering if they were being surveiled? Or didn't they care?
  1. smallmancontrov · 1790964950 · focus · HN ↗
    This was after Germany surrendered.
    I'm sure they had suspicions and cared a bit, but in order to stay silent about their passion subjects they would have had to care more than a bit.
    db48x · 1790970442 · focus · HN ↗
    And they mostly hated the Nazis and were glad to be rid of them. Plus secercy obviously no longer mattered now that a bomb had actually been used. Nothing they had to say could materially advance an enemy’s nuclear program.
  2. xhkkffbf · 1790979749 · focus · HN ↗
    Perhaps they suspected and they deliberately said things that they knew their new overlords would want to hear?
LightBug1 · 1790959722 · focus · HN ↗
Quite a quaint historical piece. In the current age, Nazi-like countries have proven they can drop enough munitions that quickly realise the equivalent, and more, destructive power of an atomic bomb. And feel free to do so.
1. bigyabai · 1790959929 · focus · HN ↗
  Today's analysts would be quick to point out that Nazi Germany's progress was about 3 weeks away from getting the bomb.
ck2 · 1790961769 · focus · HN ↗
but imagine if they did, wow, history would absolutely be completely different and they'd still be in power
speaking of which, pretty sure he's turning Iran to sand after the elections, he'll have nothing left to lose and US is only country to ever use nuclear weapons on a million innocent civilians, twice, so why stop now?
we're out of other weapons except these which seems wildly illegal to use especially on civilians
* <a href="https://apnews.com/article/iran-lamerd-us-prsm-lockheed-martin-b4a37c59bcf5d1a11eb87aa79f153648" rel="nofollow">https://apnews.com/article/iran-lamerd-us-prsm-lockheed-mart...
Imagine if Putin was using those on Ukraine civilians but US uses them no problem?
1. AnimalMuppet · 1790963180 · focus · HN ↗
  Why do you think that anyone here considers US use to be "no problem"?
  1. tempestn · 1790965847 · focus · HN ↗
    I read your parent to be saying the opposite. That more people would be upset if Putin were using weapons like these, but no one cares when the US does. (Speaking of the Lockheed PSM, not nukes.)
    AnimalMuppet · 1790967751 · focus · HN ↗
    >>> pretty sure he's turning Iran to sand after the elections, he'll have nothing left to lose and US is only country to ever use nuclear weapons on a million innocent civilians, twice, so why stop now?
    I think it's pretty clear that ck2 was talking about using nukes.
    tempestn · 1790974297 · focus · HN ↗
    Yes, obviously they were talking about nukes in the beginning of the comment, but not in the part you referenced before.
    AnimalMuppet · 1791034122 · focus · HN ↗
    Ah, I see.
2. antonvs · 1790964503 · focus · HN ↗
  > wildly illegal to use
  There's no law with any teeth at that level. Who's going to enforce it?
  Of course the ICC might issue arrest warrants for US leaders, just as they have for Netanyahu, but the practical implication of that is mostly that ICC members will be subject to attacks of all kinds.
  > Imagine if Putin was using those on Ukraine civilians but US uses them no problem?
  Since neither of those things are true, what do you think this unlikely thought experiment might tell us?
  1. cyberpunk · 1790971647 · focus · HN ↗
    The US dropping the second bomb is one of the worst crimes in human history. As far as I know, there were no consequences for this.
    So yes, the US used them, no problem.
    s1artibartfast · 1790972259 · focus · HN ↗
    What law did it break? Crime has a specific meaning different than "bad thing"
    antonvs · 1790977682 · focus · HN ↗
    I guess we're doing vibe-English now.
3. brap · 1790965447 · focus · HN ↗
  If you think US will drop a nuke on Iran you are delusional, borderline insane.
  1. fluffybucktsnek · 1790966721 · focus · HN ↗
    Are we doubting the levels of stupidity in US's current administration?
  2. leptons · 1790967362 · focus · HN ↗
    You also just described the person in charge of these weapons.
  3. buildsjets · 1790967377 · focus · HN ↗
    The President of the United States of America is delusional, and borderline insane.
    brap · 1790967569 · focus · HN ↗
    If you genuinely believe this nonsense you can probably make millions on Polymarket, go ahead.
    bryanrasmussen · 1790973000 · focus · HN ↗
    don't you make millions on Polymarket by setting a date? I personally don't doubt Trump might decide at some point that he wants to nuke someone, and then gets talked down, and then decides he wants to, and gets talked down, and then decides he wants to and then doesn't get talked down but might be kept from doing it if people are willing to stop him, but what date should I bet on this?
    hmm, I just checked polymarket, evidently it's blocked in my area. I could go to the trouble of getting around the block, but I don't really care to make millions on Trump nuking Iran or any of the other stupid things I think Trump might do because probably millions aren't going to be worth that much at that point anyway.
    But if you genuinely believe in the goodness of Donald Trump or the ability of the people around him to stand up to him, well you can probably also make some sort of money on Polymarket betting against the negative views that seem to somehow have arisen about him. Good luck.
    antonvs · 1790975578 · focus · HN ↗
    Which nonsense are you referring to? There are plenty of examples of the current US president being delusional. In fact you can even apply the DSM definition of "delusional," not just the colloquial English one, and it fits well.
    "Borderline insane" is trickier. Severely cognitively challenged would be closer to the mark.
    saulapremium · 1791013299 · focus · HN ↗
    The only thing predictable about him is his unpredictability so there is no money to be made there. That doesn't make GP wrong though.
  4. ted_dunning · 1790969124 · focus · HN ↗
    If you think that the US is the same US as ten years ago when that was an insane delusion, then you are the one smoking too much weed.
    This administration has gone to very great lengths to tear down the safety walls.
    The boats in the Caribbean demonstrate this well. Service members who object to targeting civilians without any due process are forced out.
    The difference between that is only a matter of scale. And even that scale factor has been breached in terms of the number casualties from the termination of USAID.
    It may be delusional right now to imagine service members following a nuclear attack order on Iran, but it isn't clear it will stay that way.
    db48x · 1790970545 · focus · HN ↗
    The termination of USAID caused no casualties.
  5. sitkack · 1790970927 · focus · HN ↗
    Seeing as the pentagon has no issue with volunteering for extra judicial murder, it is not off the table. at all.
    s1artibartfast · 1790972148 · focus · HN ↗
    What odds would you give it?
4. ch4s3 · 1790965558 · focus · HN ↗
  > US is only country to ever use nuclear weapons on a million innocent civilians
  Sure but in the context of WWII, area bombing was the predominant military doctrine of both sides, and Japan famously killed hundreds of thousands of civilians in a far more grisly fashion[1]. The Japanese army killed as many as 500,000 civilians with chemical weapons[2]. Some 20 million Chinese civilians died as a direct or indirect result of the Japanese invasion. You'll find little sympathy for Japan in East Asian histories of WWII, the list of war crimes committed by Japan during the war makes other theaters of the war look almost tame by comparison.
  Now none of this excuses wide area civilian bombing, but it's also not like guided munitions even existed in 1945 and Japanese war production was spread out and diffuse within it's cities.
  [1] <a href="https://en.wikipedia.org/wiki/Nanjing_Massacre" rel="nofollow">https://en.wikipedia.org/wiki/Nanjing_Massacre
  [2] <a href="https://www.history.navy.mil/about-us/leadership/director/directors-corner/h-grams/h-gram-057/h-057-2.html" rel="nofollow">https://www.history.navy.mil/about-us/leadership/director/di...
5. leptons · 1790967429 · focus · HN ↗
  If the US did use a nuke in Iran, you can bet the very next day (or hour) that a nuke will fall on Ukraine.
rgrieselhuber · 1790963524 · focus · HN ↗
<a href="https://www.bbc.co.uk/programmes/p0150vqp" rel="nofollow">https://www.bbc.co.uk/programmes/p0150vqp
sharpshadow · 1790963928 · focus · HN ↗
After the Norway Hydro plant sabotage in 1943 they didn’t had more heavy water left than what they used 1945 in Haigerloch. If they would have had the resources uninterrupted they very likely would have came faster and in time to the bomb. From my limited standpoint I would say the Norsk Hyrdo Plant sabotage in Operation Gunnerside prevented nuclear Germany not the incapability of German scientists.
WalterBright · 1790963993 · focus · HN ↗
It's generally forgotten that Japan was also developing a nuclear bomb. They were a long ways from making a viable one, though. It was abandoned after the surrender.
1. fusslo · 1790964260 · focus · HN ↗
  I cant remember which, but a documentary about the bombing of Hiroshima and Nagasaki said that after the first bomb, Japanese scientists were deployed to confirm or deny the US's claim of an atomic weapon.
  If I remember right, the Japanese scientists confirmed signs of an atomic explosion, but the leaders were stuck in a debate as to whether or not to accept the findings
  Maybe someone better educated can correct me if I didn't get that history quite right
  Edit:
  <a href="https://en.wikipedia.org/wiki/Yoshio_Nishina#Atomic_bomb" rel="nofollow">https://en.wikipedia.org/wiki/Yoshio_Nishina#Atomic_bomb
  <a href="https://en.wikipedia.org/wiki/Bunsaku_Arakatsu" rel="nofollow">https://en.wikipedia.org/wiki/Bunsaku_Arakatsu (check out his academic advisor!)
  1. 7speter · 1790972386 · focus · HN ↗
    All the people dying from side effects of radiation wasn’t enough proof that an atomic weapon was used?
    AngryData · 1790973475 · focus · HN ↗
    Well the effects of radiation were still poorly understood, but also there wasn't that much radioactive material left over in any concentration. And the gamma ray blast would appear superficially like normal burns from being near a firebomb until atleast a few days later.
    Contrary to Fallout lore, most nuclear bombs dont leave much concentrated radioactive material unless it was done on purpose. You either need a shittier and smaller explosion with the same material, or you need a ground burst which reduces the effective blast area.
    The US was on ground zero in under 2 weeks in Japan and couldn't detect anything over the background in radioactive isotopes.
    Lumich · 1791020983 · focus · HN ↗
    « And the gamma ray blast would appear superficially like normal burns from being near a firebomb until atleast a few days later. »
    Would it? How so?
    First, the notion of “normal burns from being near a firebomb” is inadequate. There are various types of firebombs. The ones “generously” employed by Uncle Sam against the Japanese (primarily civilians, and later idem against the Koreans and the Vietnamese) are napalm bombs. The way they work is that burning napalm is blasted about in lumps and sticks to anything it hits, including clothes and human skin. The injuries caused by napalm lumps are special. They're called keloids.
    Figure 9.3 on page 171 of Palmer's book (free PDF available, link in 49938615, which is among the comments on this topic) shows keloid burns in Hiroshima bombing victims. These have been interpreted as “flash burns”. However, this defies common sense. First, they show characteristically strong locality, irregular shapes, sharply defined edges, and look exactly like napalm burns. Second, how would you explain a hypothetical “flash” (of whatever nature) from a distance more than a couple inches away to produce such conspicuously localized injuries? (And even from ten inches away you'd need strong directionality.) The forensics flatly contradict and preclude such a “flash” interpretation.
    Palmer, who is an MD, found that not much can be found about napalm in the medical literature, which curiously contrasts with its very wide-spread application against humans by the U.S. Air Force (p.140, referred to on p.175 and p.241):
    As of this writing (in 2019), a simple search for “napalm” on PubMed retrieves 29 articles, of which only 7 (seven) are written in English, and none of these provides much useful detail.
  2. WalterBright · 1790984214 · focus · HN ↗
    The leaders knew immediately that it was an atomic bomb.
    Books:
    Code-Name Downfall by Allen
    Downfall by Frank
    defrost · 1791010349 · focus · HN ↗
    They rebuilt Tokyo that fast already ?
    The strikes conducted by the USAAF on the night of 9–10 March 1945, codenamed Operation Meetinghouse, constitute the single deadliest and most destructive aerial bombing raid in human history. Sixteen square miles (41 km2; 10,000 acres) of central Tokyo was destroyed, leaving an estimated 100,000 civilians dead and over one million homeless.
    ~ <a href="https://en.wikipedia.org/wiki/Bombing_of_Tokyo" rel="nofollow">https://en.wikipedia.org/wiki/Bombing_of_Tokyo
    Made that "third bomb on Tokyo" fear was a bit made up and ahistoric.
  3. Lumich · 1791015468 · focus · HN ↗
    « signs of an atomic explosion »
    I'm curious. We know that there's a lot of energy in the atom. Some of it can be released by fission, which results in fission products, radiation, and heat.
    However, there doesn't seem to be anything in the process that would account for any sort of explosion. Radiation doesn't contribute. Heat alone is insufficient. In addition, you need an instant and manyfold increase in the volume of matter generated on the other side of the reaction. With TNT, for example, this increase is three orders of magnitude. Fission products are completely insignificant in this respect.
    So nothing comparable exists for nuclear fission, else it would be a problem for reactors. So how can it explode? What is the mechanism?
    womble2 · 1791019321 · focus · HN ↗
    Heat alone is not insufficient, the heat generated is so intense that is turns the surrounding air into a plasma which then absorbs the x-rays emitted creating a stupendous over-pressure in the air which drives the shockwave.
    Reactors don't explode because the amount of heat then generate is carefully monitored and matched the the rate at which that heat can be pulled from the reactor and converted into work.
    Lumich · 1791027824 · focus · HN ↗
    Thanks. This is a novel explanation to me. So to rephrase, some volume of air (~1,2 kg/m³ at sea level) is “plasmarized” and then eats the X-rays, upon which it expands in a shockwave.
    It is usually stated, however, that the X-rays go first, and at the speed of light. Plasmarization, OTOH, would be subject to some inertia, however little, wouldn't it. So there'd be a delay before plasma formation, and the X-rays would already be “over the horizon” (joke – they wouldn't follow Earth's curvature, would they).
    womble2 · 1791040059 · focus · HN ↗
    The x-rays aren't just emitted in a single moment, they are the result of the initial core heating up to millions of degrees, so the light they emit just as a result of being hot is in the x-ray and lasts for some amount of time. This is long enough to generate the ionised air with continues to expand and absorb more x-rays until the initial core cools down somewhat. At that point you have a large amount of incredibly hot, incredibly high pressure plasma which then expands and causes the shockwave.
    Someone · 1791030686 · focus · HN ↗
    [delayed]
    Lumich · 1791123537 · focus · HN ↗
    [dead]
2. colechristensen · 1790966157 · focus · HN ↗
  Hideki Yukawa was the first Japanese Nobel Prize winner for his work on strong-force related physics in the 1930s.
  >It was abandoned after the surrender.
  Japan is strongly believed to be on the order of months away from assembling a nuclear weapon, and not just one, they have the materials for many. For them it is not geopolitically useful to actually finish a weapon, but they are more than capable.
  1. buildsjets · 1790966956 · focus · HN ↗
    Do you have a reliable source you can share which supports that claim? Because el wiki says nothing of the sort. It discusses two main projects, "Ni-Go" and "F-Go", neither of which successfully enriched fissile material. One was built but did not operate successfully, the other was not built.
    <a href="https://en.wikipedia.org/wiki/Japanese_nuclear_weapons_programs" rel="nofollow">https://en.wikipedia.org/wiki/Japanese_nuclear_weapons_progr...
    rawling · 1790967096 · focus · HN ↗
    > Today, Japan is considered to be a latent or threshold nuclear state, capable of developing weapons in a short timespan. It is unique among non-nuclear weapons states in that it possesses a full nuclear fuel cycle and plutonium stockpile, as part of its civilian nuclear energy industry, and advanced developments in the industries necessary to make nuclear weapons.
    mmmBacon · 1790970884 · focus · HN ↗
    While your comment is true today. It doesn’t support the GP’s claim that Japan was near a nuclear weapon at the end of WW2 and only lacked the will to do so.
    OJFord · 1790971951 · focus · HN ↗
    That was not the claim. They said 'is on the order of months away', not 'was'.
    colechristensen · 1791135470 · focus · HN ↗
    correct
  2. Lumich · 1790977488 · focus · HN ↗
    « For them it is not geopolitically useful to actually finish a weapon »
    Why, they could take their revenge, couldn't they.
    This whole thing is stories built upon stories built upon stories. It's stories all the way down till you reach The World Set Free by British propaganda writer H.G. Wells, published in 1913–14 as part of the British war propaganda preparations against Germany. I don't recommend the book, it's psychologically dull and constructed, but that's where Leo Szilárd picked up the idea of an “atomic superbomb” in 1932 when reading the novel, which led to the Einstein letter in 1939. Well, according to the story anyway.
    [deleted] · 1790981687 · focus · HN ↗
    [deleted]
    WalterBright · 1790984509 · focus · HN ↗
    A more reliable account is "The Making of the Atomic Bomb" by Rhodes.
    Lumich · 1791009906 · focus · HN ↗
    He certainly had the benefit of hindsight. I haven't read it yet.
    Meanwhile, here's an interesting 1979 “oral history” testimony by general Crawford Sams, medical expert and administrator, who was very close to the application of the “final product”, as it was his job to shape the narrative in a certain way, as part of which he established the Atomic Bomb Casualty Commission:
    I mentioned deterrents against war. There was a letter brought over by this first group that came up to Japan from the Philippines with me, from the Manhattan Project, in which the President was looking for a new deterrent against a future war, because air power had failed. […] So the object of this instruction, called *Letter of Instruction*, was “You will play up the devastating effect of the atomic bomb.” All right? So I was the one who set the deadline this time. Anybody who had been in Hiroshima and died within six months, whether they got run over by a bicycle or whatnot, would be credited to the atomic bomb.
    Destruction took time (as elsewhere):
    We built up the evidence to show on a cookie-cutter basis that it took about thirty-six hours for about two-thirds of that town to burn.
    Didn't happen in an instant:
    You see, it wasn’t “Bing” like the publicity here [said]: a bomb went off and a city disappeared. No such thing happened. That was the propaganda for deterrent. They’re talking about after that, “One bomb and away goes Chicago,” you know?
    More here, with links to source (WUSTL, the transcript is much better than the audio, which is really low quality):
    <a href="https://telegra.ph/Crawford-Sams-12-05" rel="nofollow">https://telegra.ph/Crawford-Sams-12-05
    Lumich · 1791119875 · focus · HN ↗
    [dead]
  3. WalterBright · 1790984330 · focus · HN ↗
    I don't buy that. To generate the enriched uranium requires a lot of time and an enormous investment of money.
    philipkglass · 1791044475 · focus · HN ↗
    Japan has a large inventory of plutonium recycled from used power reactor fuel:
    <a href="https://www.aec.go.jp/bunya/04/plutonium/20260805_e.pdf" rel="nofollow">https://www.aec.go.jp/bunya/04/plutonium/20260805_e.pdf
    As of the end of 2025, the total amount of Japan’s separated plutonium managed both within and outside Japan was approximately 44.4 tons, of which approximately 9.9 tons were held domestically and approximately 34.5 tons were held abroad.
    Despite the nomenclature, weapons grade plutonium is not necessary to make nuclear weapons. Reactor grade plutonium has more problems with predetonation ("fizzle") and decay heat management, but both obstacles can be bypassed by design changes. In particular, "boosting" with a mixture of deuterium and tritium overcomes predetonation problems and can ensure repeatable high yields even with plutonium containing a high fraction of Pu-240.
    <a href="https://en.wikipedia.org/wiki/Boosted_fission_weapon#Gas_boosting" rel="nofollow">https://en.wikipedia.org/wiki/Boosted_fission_weapon#Gas_boo...
    The fusion reaction rate typically becomes significant at 20 to 30 megakelvins. This temperature is reached at very low efficiencies, when less than 1% of the fissile material has fissioned (corresponding to a yield in the range of hundreds of tons of TNT). Since implosion weapons can be designed that will achieve yields in this range even if neutrons are present at the moment of criticality, fusion boosting allows the manufacture of efficient weapons that are immune to predetonation. Elimination of this hazard is a very important advantage in using boosting.
    This design hardens weapons against neutrons from nuclear interceptors and against neutrons generated within the core itself, e.g. spontaneous fission from "dirty" reactor plutonium.
    Gas boosted bombs are more mechanically complex than the bombs of the 1940s, but the US started building them in the 1950s. Japan could easily manage the complexity today. Japan has also operated its Tritium Process Laboratory since the late 1980s, with capacity to handle 16 grams of tritium at a time. That's not much, but an individual boosted warhead may need only 3 grams of tritium.
sandworm101 · 1790964698 · focus · HN ↗
The science is only half of the question. Another substantial issue was, even with equal knowledge to the US, did German and/or Japan have the industrial capacity to create a nuclear weapon?
Fun fact also: For all the effort put into the Manhattan project, MORE time/resources were spent on its eventual delivery system (the B-29) than the bomb itself. So even if Germany/Japan had a nuclear bomb, could they have also developed a practical delivery method, something capable enough to trust with such a weapon?
I had this discussion last week with someone who asked about whether Canada could build a bomb. Ya. Easy. Modern industrial capacities dwarf anything from the 1940s and Canada certainly has the brainpower and raw materials. But could Canada so easily develop a delivery platform, say an ICBM or stealth fighter? Likely not.
1. comeonbro · 1790964940 · focus · HN ↗
  It's not comparing like with like, but the V-weapons program cost about as much as the Manhattan Project.
  1. delichon · 1790965671 · focus · HN ↗
    The Manhattan Project employed around 130,000 people compared to something like 17,000 on the V-2 project (plus 60,000 concentration camp prisoners). Cost comparisons are in the neighborhood of $1.9B to $800M.
2. delichon · 1790965359 · focus · HN ↗
  Germany did put U-boats off of the US East Coast. It would probably be a one way trip to put one off of the Brooklyn docks. But if they had two and used the first to clear a path for the second, it could have worked.
  1. sandworm101 · 1790965800 · focus · HN ↗
    Yes but that would be wildly inefficient. A nuke on the ground ("lay-down" delivery) is already maybe 40% as powerful as one in the air. Put it under even a few feet of water and that becomes only 20% as most of the energy goes sideways/down through water/dirt rather than directly at the target buildings. Water is shockingly dense at scale.
    torginus · 1790966986 · focus · HN ↗
    I'm not sure, water is very good at conducting shockwaves. If you had an aquarium the size of an olympic swimming pool you could kill all of them by dropping a hand grenade in it.
    Teever · 1790969868 · focus · HN ↗
    Inefficient compared to a B-29 dropping a bomb over a city but not inefficient compared to whatever other means (if any) Germany had of attacking an east cost city like New York.
    Rest assured that if this alternate history scenario had occurred historians would not be talking about the inefficiency of the attack, they would be talking about the most devastating attack that Germany was able to conduct against Americans on their own soil during the war. It would have completely changed the American mindset and culture forever.
3. philipkglass · 1790965430 · focus · HN ↗
  The Manhattan Project was so very expensive because they pursued plutonium production and uranium enrichment simultaneously. They also developed three uranium enrichment methods in parallel. Two of these actually contributed to the Hiroshima bomb. The uranium enrichment projects were much more expensive than the plutonium project. Britain and France built their first atomic bombs much more economically by pursuing the plutonium path alone.
4. simonh · 1790965836 · focus · HN ↗
  If North Korea can manage it, I think with a bit of commitment it should be doable.
5. throwawayffffas · 1790966542 · focus · HN ↗
  No that's the entire point of the article even if they had the physics down, they did not have enough uranium in the whole of Germany for a working reactor let alone a uranium fission bomb.
  The delivery method was much closer in reach than the bomb, given their missile program if they had a concrete target they could probably easily build a scaled up version of a v1 or v2 to deliver the weapon.
  1. [deleted] · 1790983227 · focus · HN ↗
    [deleted]
  2. wolvoleo · 1790993208 · focus · HN ↗
    They could have mined enough. They controlled the czech republic which provided a lot of the Soviet's nuclear materials.
6. gopher_space · 1790966582 · focus · HN ↗
  The thought experiments around Mutually Assured Destruction back in the day showed us that you don't actually need a delivery system to participate.
  1. sitkack · 1790970445 · focus · HN ↗
    A big enough bomb and it can be fixed in place.
kjander79 · 1790965857 · focus · HN ↗
This is an awesome read, and likely correct in the narrative, but the cubes they have at hand to study have a bit of a provenance problem - how do we know they were the ones used for the German research?
At any rate, getting a reactor running still was a long way from the industrial capacity the Americans used to get a working device. Industrial capacity Germany just didn't have late in the war. And after Afrika Korps' defeat, they weren't getting any easily accessible materials anymore.
1. peri-cl · 1790966539 · focus · HN ↗
  Among other things (from the article and the linked paper):
  > "handwritten note accompanying the cube: “Taken from the reactor that [Adolf] Hitler tried to build”"
  > "Most of these surviving cubes, including those analyzed in this work, can be traced directly back to the individuals who removed them from Germany during the war, providing proof of their provenance" [in particular, there's other cubes, and they're consistent]
  > "small notches were cut to fit the aluminum wire that tied each chain together"
2. monocasa · 1790967283 · focus · HN ↗
  We have very good tracking of these kinds of things, just based on the material properties of the samples.
  To the point where we found some material in what purported to be fresh ore that had clearly been in a reactor at one point, but couldn't track down which particular reactor it matched. For a while there was a bit of a scare that some nation had a reactor unknown to international authorities that was selling its waste products on the open market.
  Turns out there was just an ore deposit that had exactly the correct conditions to be a low grade (but completely natural) nuclear reactor in Oklo, Gabon.
3. Lumich · 1790975208 · focus · HN ↗
  « likely correct in the narrative » — What if it is built on flawed premises?
  I was keyed up for my first view of an atom-bombed city, prepared for the radically new sights suggested by the exciting descriptions I had read and heard. But to my utter astonishment, Hiroshima from the air looked exactly like all the other burned-out cities I had observed!
  Alexander de Seversky, Air Power: Key to Survival, 1950
  quoted in:
  Michael Palmer, Hiroshima revisited, 2020–23
  <a href="https://mpalmer.heresy.is/webnotes/HR/" rel="nofollow">https://mpalmer.heresy.is/webnotes/HR/
  1. ajnin · 1791027618 · focus · HN ↗
    That's the second puzzling comment you've posted on this subject. Are you suggesting atom bombs don't exist?
    Lumich · 1791058062 · focus · HN ↗
    I've learnt that flat out statements aren't always the best way. I suggest curious minds consider the evidence laid out in Palmer's book, which is not only free but also a true pioneering work, to then “come to their own conclusions” (if they're into that kind of thing – not everyone is).
    I had never really understood why in the early 90s “nuclear weapons” ceased to be “a problem” (a media talking point) moreless overnight “when the Wall came down”, as the arsenals still existed. A dozen years later I realized the Russians kept talking about them, and I was worried about “stability”.
    And there were other things I couldn't make sense of – such as what does it mean for an aircraft to be “nuclear-capable”? I mean – there's a payload, and there's speed and altitude, and there may be safety concerns, but nothing really seems to fit when you look at what's considered “capable” and what's not.
    And why did we have barrages to stop tank armies entering “from the East”?
    And why spend so much on military in the first place when the bomb dwarfs everything? Why all this insanity?
    Another dozen years later I found that same Swedish naval engineer whom Palmer would later also find in the exact same way, and whom he mentions in the preface. It was a bit like “tolle, lege” although of course I don't compare to Augustine.
    And then the insanity started making sense again, but in a very different way.
    But there's something else that strikes me profoundly when I read discussions such as these. It's not about the topic, it's about the participants. It's the way they talk about it – the way “the Bomb” has become an object of both erudition and veneration. “The Bomb” is studied and idolized, intellectually hugged and worshipped – while the victims are a mere projection screen for the greatness of “the Bomb”.
    How can that be?
    To me, the psychology of things is often the most interesting aspect. And I think what we have here is a cover story, a self-serving cover story, and that is not an accident.
    ajnin · 1791075319 · focus · HN ↗
    A cover story for what ? We have eyewitnesses of Hiroshima. We have videos of atomic bomb tests. We have seismic recordings of underground blasts. Multiple countries claim to have independently developed the bomb. A coverup on a global scale, lasting for decades, implicating people from the military, scientists, everyday people from many countries, without a single person breaking secrecy. Why ?
    Lumich · 1791125514 · focus · HN ↗
    I'd reply but it's pointless, all my comments are now stillborn, dead on arrival. It appears some people on HN, despite all the talk about “curiosity”, don't like seeing their topics of predilection and veneration challenged by views and evidence that could lead people to reconsider whether the establishment view is correct at all.
4. pseudohadamard · 1791025643 · focus · HN ↗
  What the story completely omits to mention is that the entire field was seen as "Jewish science" and therefore verboten for any kind of real funding or support. It never had a chance from the get-go.
  Just goes to show what happens when a world-leading science power lets political superstition overrule the science.
Danox · 1790966531 · focus · HN ↗
Germany’s racism/ethnic hate killed their efforts for the bomb..
1. unrented7977 · 1790967239 · focus · HN ↗
  As much as I'm sure that gives you the warm fuzzies to think about, it's utter nonsense. That's not how this works.
  1. lambdaone · 1790968110 · focus · HN ↗
    It's absolutely how it worked for the Manhattan Project.
    slashdev · 1790972207 · focus · HN ↗
    How so?
    w0de0 · 1790978652 · focus · HN ↗
    Oppenheimer, as well as many other Manhattan Project researchers (eg Rabi & Weisskopf), were first or second generation German-Jewish immigrants/refugees. Max Bonn, Oppenheimer’s mentor, was also a refugee in the end; Oppenheimer was born to immigrants in the US but studied under Bonn in Germany prewar.
    Moreover, the physical foundation for atomic power was largely the work of German, often German-Jewish, scientists.
    So it’s plausible to suppose a counter-factual in which Germany, one less crippled by bigotry (and it is a disability…), develops the bomb.
    And it’s not just the bigotry: it’s the anti-intellectualism. Einstein could write a letter to a well-educated patrician of the New York Dutch aristocracy (FDR), and so help change the world. The pig farmer and the corporal would never have read such a letter (even if were they not already trying to murder the writer and all his cousins for nonsense reasons).
  2. mrguyorama · 1790972369 · focus · HN ↗
    Hitler explicitly called particle and nuclear physics "Jew science" and disregarded it. For a man who adored mythical wonder weapons that did not pencil out at all, he did not put effort into building nuclear bombs.
    Add to that, most of the physicists at that point in history were very unhappy with Fascism in general, and fled Italy or Germany when they could.
    Many of those who came and helped the US build it's bomb did so reluctantly. Only really Teller seemed genuinely excited about big nuclear bombs. Everyone else wanted anyone but the Nazis to get it.
    However, it's important to note that it's very unlikely anyone else had the resources to actually devote to their equivalent of the Manhattan project, so even though pretty much every state at the time had a nuclear bomb program of some sort, the vast majority were more exploratory than production focused.
2. KetoManx64 · 1790972315 · focus · HN ↗
  > Germany’s racism/ethnic/religious hate killed their efforts for the bomb..
  Interesting fact: Ghislane Maxwell's (yes the Epstein one) father was involved in the publishing of all the history textbooks that are taught in public schools.
  1. killingtime74 · 1790973077 · focus · HN ↗
    Where? in America or in Germany? it's kind of ambiguous what you're saying.
    roryirvine · 1791034505 · focus · HN ↗
    Mostly Britain, though Maxwell did also very briefly control both Prentice Hall and the American side of Macmillan from 1988/9.
    Some of the (rather convoluted) history is at <a href="https://en.wikipedia.org/wiki/Macmillan_Inc.#Mergers_and_end" rel="nofollow">https://en.wikipedia.org/wiki/Macmillan_Inc.#Mergers_and_end - but there's not much evidence for any conspiracy GP may have been hinting at.
    (Cap'n Bob Maxwell was essentially the left-wing Rupert Murdoch - big on tabloid journalism and building media empires through fair means and foul. A hugely controversial character, but his involvement in textbook publishing was fairly incidental)
rurban · 1790967891 · focus · HN ↗
What they didn't mention is that German had the worlds largest Uranium reserves those times, even larger than the famous Belgian-Kongo mines. They didn't knew it then. But the Nazis promised the miners to close the unhealthy mines, the avg. age of a miner was 45. They didn't, but later the Russians used this German and Czech uranium to produce their nuclear arsenal. What Germany missed was to enrich the uranium. Siemens could have done it, but Speer/Heisenberg probably missed that opportunity.
1. Lumich · 1791024939 · focus · HN ↗
  « later the Russians used this German and Czech uranium to produce their nuclear arsenal. What Germany missed was to enrich the uranium. »
  Which would be all the more curious, if true, as we were probably on the right track, i.e. judging by the 1950s Soviet development of GUZ enrichment (Gas-Ultra-Zentrifugen), “with a little help from their German friends”, such as Gernot Zippe and Manfred von Ardenne, while “the West” was far behind in this domain.
  <a href="https://de.wikipedia.org/wiki/Gernot_Zippe" rel="nofollow">https://de.wikipedia.org/wiki/Gernot_Zippe
  Zippe kehrte 1957 nach Österreich zurück. Als er 1957 in Amsterdam eine Konferenz zur Zentrifugen-Forschung besuchte, stellte er fest, dass die Forschung im Westen weit zurücklag.
  The Soviets had the first nuclear power station (Obninsk, 1954), whereas the USA was focussed on “exterminating enemies”.
  During the Manhattan Project, Usanians didn't get centrifugation to work properly, and their other enrichment processes were inefficient. Curious, curious.

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