[HN Gopher] The Demon Core and the Strange Death of Louis Slotin...
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The Demon Core and the Strange Death of Louis Slotin (2016)
Author : sklargh
Score : 65 points
Date : 2023-05-21 16:14 UTC (1 days ago)
(HTM) web link (www.newyorker.com)
(TXT) w3m dump (www.newyorker.com)
| automatic6131 wrote:
| In summary: https://i.kym-
| cdn.com/photos/images/newsfeed/002/111/759/fe2...
| spondylosaurus wrote:
| Wow, I haven't seen the Ol' Spicy Keychain in _years_... this
| takes me back!
| nielsbot wrote:
| wow. where's this from?
| ablation wrote:
| It's an edit this: https://knowyourmeme.com/memes/the-ol-
| spicy-keychain
| [deleted]
| ndsipa_pomu wrote:
| What I've found surprising is that there's a whole genre of memes
| based around the demon core. (e.g.
| https://imgur.com/t/demon_core)
|
| There's something uniquely terrifying about a substance that is
| safe to handle in one orientation, but utterly deadly in another.
| akiselev wrote:
| It's not exactly safe to handle, it's just not acutely fatal
| until it's supercritical. Plutonium forms an oxide that easily
| flakes off so handling any sized demon core is full of danger.
| Bump it against something, scratch it, or even if the
| environment is particularly humid the powder will get
| everywhere.
|
| Ingesting or inhaling any of that oxide would result in a slow
| and very painful death.
| ortusdux wrote:
| The core was nickel plated to prevent oxidation.
| shadowgovt wrote:
| Gallows humor is a popular go-to for multiple popular internet
| fora. The topic was also brought up by a few influential
| YouTube science explainers (here's Kyle Hill semi-apologizing
| for popularizing the meme:
| https://www.youtube.com/watch?v=z497lu4t5XI, although I don't
| think the Google Search history suggests his 2017 video was the
| primary mover of the popularity spike).
|
| In addition to the aspect of its horror that you highlighted,
| radiation is also a go-to science bogeyman because how how
| cause and effect are perceptually disjoint. You can feel
| absolutely fine absorbing way past an LD50 of radiation at the
| moment it happens; the suffering comes later, from hours to
| days later. Like firing up a computer with an already-damaged
| hard drive, you won't have a problem until the OS needs that
| data and loads garbage instead of useful routines.
| morkalork wrote:
| Always fun to spot one in the wild too, like this example:
| https://www.reddit.com/r/NonCredibleDefense/comments/139kybg...
| akira2501 wrote:
| I've always found the Tokaimura accidents to be a little
| "creepier." A vat of liquid can end up in a state of mixture
| and configuration that causes it suddenly become critical. [0]
|
| [0]: https://en.wikipedia.org/wiki/Tokaimura_nuclear_accidents
| lxgr wrote:
| > A vat of liquid can end up in a state of mixture and
| configuration that causes it suddenly become critical.
|
| It can indeed: https://en.wikipedia.org/wiki/Cecil_Kelley_cri
| ticality_accid...
| lordfrito wrote:
| Wow what an interesting article, especially the part about
| the plutonium liquid vortex reaching criticality.
| Fascinating (but sad) stuff. Shame how his widow was
| treated afterwards.
| jchw wrote:
| Not to mention Karameru's recurring character "Demon Core-kun".
|
| https://m.youtube.com/watch?v=6ZIjbX1gj88
|
| As bizarre as it is, Karameru's weird shorts probably brought a
| lot of attention to the Demon Core seeing as they're rather
| popular (even just that one is currently at 4.1M views.)
|
| I'd wager this is the weirdest thing I've ever found an excuse
| to link to on HN.
| kens wrote:
| Yes, it's a bit surprising how much of a meme the demon core is
| on Twitter. Some other popular radiation memes: "drop and run",
| LANL plutonium rods, "3.6 Roentgen not great not terrible" and
| "This is not a place of honor". Am I missing any?
| Tade0 wrote:
| I suppose "Completely normal phenomenon" fits the bill.
| iancmceachern wrote:
| There was also a whole thing where a guy faked creating one and
| the subsequent radiation burns, etc. And shared it all on
| social media.
| AlexandrB wrote:
| Are you maybe thinking of this:
| https://m.youtube.com/watch?v=VMyNQCVS410
|
| That wasn't something quite as dangerous as the demon core,
| but a fake "orphan source".
| korroziya wrote:
| The 'ol spicy ball.
| ttul wrote:
| I wonder if we will one day look back and view our early AGI
| experiments and ask, "How could they have been so careless?"
| progre wrote:
| Lots of people are saying that now
| kobalsky wrote:
| I recall reading that their colleagues were saying these guys
| would fry themselves long before it happened.
| chasd00 wrote:
| > ... early AGI experiments and ask, "How could they have been
| so careless?"
|
| what remains to look back may proclaim these times as the birth
| of their universe ;)
| lisasays wrote:
| https://archive.is/HopP4
| nimbius wrote:
| Slotin was an arrogant ass. per wikipedia:
|
| "Under Slotin's own unapproved protocol, the shims were not used
| and the only thing preventing the closure was the blade of a
| standard flat-tipped screwdriver manipulated in Slotin's other
| hand. Slotin, who was given to bravado, became the local expert,
| performing the test on almost a dozen occasions, often in his
| trademark blue jeans and cowboy boots, in front of a roomful of
| observers."
|
| play stupid games, win stupid prizes. his only salvation was that
| he sacrificed himself to save his colleagues.
|
| there were also other, safer ways to do it
|
| "Enrico Fermi reportedly told Slotin and others they would be
| "dead within a year" if they continued performing the test in
| that manner."
| debacle wrote:
| As we progress scientifically, our ability to accidentally off
| ourselves will only continue to grow.
| rowanG077 wrote:
| Increase in number of ways? Maybe. Increase in accidents? Most
| definitely not.
| candiddevmike wrote:
| ARS has to be one of the worst ways to go, and probably the most
| unnatural?
| shadowgovt wrote:
| It's an interesting topic, what would be the most unnatural way
| to die.
|
| At some point, I got in a conversation about what would happen
| if you drank nothing but heavy water. The short answer is that
| yes, this would kill you; the differing molecular weight
| between molecules built with heavy hydrogen and regular
| hydrogen will eventually add up to disruption of metabolic
| processes in ways that we haven't even researched. But we
| haven't researched them because it would cost an _absolute
| fortune_ to get enough of the stuff to do yourself in.
|
| This would be a suicide reserved for billionaires.
| causi wrote:
| The toxicity of heavy water is not related to its molecular
| weight, rather to the difference in strength of its hydrogen
| bonds.
| shadowgovt wrote:
| I was under the impression that the difference in mass
| results in slowing down metabolic processes (mainly because
| it takes more energy per unit time to move a more massive
| molecule). I wouldn't expect the hydrogen bond strength to
| be affected because hydrogen bonds are electromagnetic
| bonds, and the electromagnetic properties of deuterium and
| (H1) water are the same (other than the mass-effected ones;
| heavy hydrogen in an electric field will accelerate more
| slowly than light hydrogen, but that's because it's more
| massive, not because it's more weakly coupled to the
| electric field).
| causi wrote:
| Heavy water hydrogen bonds are a couple percent stronger
| because the molecules themselves are very slightly
| smaller. Smaller molecules result in a shorter range of
| vibration at a given temperature, hence less inherent
| "fighting" of the hydrogen bond.
| retrac wrote:
| Heavy water's only about $1000 a litre in bulk. Certainly
| cheap enough to run experiments on rats and small plants.
| Such experiments have been done. That's how we know it'll
| kill you.
|
| Its toxicity profile is kind of interesting. In almost all
| eukaryotes (plants, animals, fungi) low concentrations (1 -
| 10%) seem to have no obvious effect at all, while around 25%
| it seems to cause temporary sterility - the gametes seem
| particularly sensitive. As it approaches 50%, cell
| reproduction stops and death is rapid. Very few eukaryotes
| can survive >50% heavy water in their cells. Though a few
| types of yeast and single-celled plants seem to be able to
| survive in conditions like many bacteria can - up to 95% or
| more heavy water. But all kinds of life die at 100% heavy
| water, as far as I know.
|
| https://en.wikipedia.org/wiki/Heavy_water#Effect_on_biologic.
| ..
| [deleted]
| ndsipa_pomu wrote:
| As an aside, it's surprising how "safe" plutonium can be even
| when it's being injected into your bloodstream
|
| https://en.wikipedia.org/wiki/Human_radiation_experiments
|
| https://en.wikipedia.org/wiki/Albert_Stevens
| Symmetry wrote:
| Surely not that much. The LD50 of heavy water is really high
| at 30% of body weight[1] but it's only about $10,000 per kg.
| So even the most obese millionaire should be able to kill
| themselves this way if they really want to.
|
| That's part of why thermonuclear weapons have such a
| disturbingly high "bang for the buck." The enriched uranium
| or plutonium primary is really expensive. So is the rocket
| that gets it where it's going. But the lithium deuteride that
| makes up the fusion fuel is comparatively dirt cheap.
|
| [1]https://arxiv.org/pdf/physics/0206076.pdf
| jabl wrote:
| > That's part of why thermonuclear weapons have such a
| disturbingly high "bang for the buck." The enriched uranium
| or plutonium primary is really expensive. So is the rocket
| that gets it where it's going. But the lithium deuteride
| that makes up the fusion fuel is comparatively dirt cheap.
|
| No idea what the cost of enriched U, Pu, or lithium
| deuteride is, but I'll note that A) current day
| thermonuclear warheads deliver an estimated 50% of the
| total output through fission of enriched U (casing) and Pu
| (primary) B) the lithium in lithium deuteride, as well as
| the deuterium, need to be enriched, so probably not quite
| dirt cheap (depends on your definition of dirt cheap I
| guess)?
| tantalor wrote:
| idk about "unnatural", it's basically death by physics. You are
| killed by the universe. Sounds natural to me.
|
| I'd put in the same category as falling from a great height.
| StrangeATractor wrote:
| > I'd put in the same category as falling from a great height
|
| Yeah, onto the surface of the sun.
| michaelcampbell wrote:
| One way to categorize, I guess.
|
| Prior to humans enriching radioactive materials, how many
| humans died from ARS vs. falling from a great height?
| dmd wrote:
| What other kind of death is there?
| Cyberdog wrote:
| Well, if we want to put it that way, _all_ deaths are death
| by physics, aren 't they? Including murder.
| bjt2n3904 wrote:
| The fact that Daghlian and Slotin died in the same hospital bed
| has always been a sobering thought. "Well, that does it" are
| harrowing words.
|
| There are famous engineering incidents that are good to study --
| the Challenger disaster, the Minnesota Bridge collapse, the
| Therac 25... But compared with the LANL Criticality incident,
| there's something different. The former are all technical failure
| analysis.
|
| This incident is almost existential in it's implications, like
| Shelly's Frankenstein. A discussion on the nature of humanity.
| dang wrote:
| Related:
|
| _The Demon Core and the Strange Death of Louis Slotin_ -
| https://news.ycombinator.com/item?id=25317021 - Dec 2020 (1
| comment)
|
| _Demon Core: The Strange Death of Louis Slotin (2016)_ -
| https://news.ycombinator.com/item?id=20744425 - Aug 2019 (22
| comments)
|
| _Demon Core: The Strange Death of Physicist Louis Slotin_ -
| https://news.ycombinator.com/item?id=11749742 - May 2016 (34
| comments)
| CottonMcKnight wrote:
| Dramatized in a scene from "Fat Man and Little Boy"
|
| https://www.youtube.com/watch?v=AQ0P7R9CfCY
| ortusdux wrote:
| I wonder if this event will be in the new Oppenheimer movie. I do
| like John Cusack's rendition:
| https://www.youtube.com/watch?v=AQ0P7R9CfCY
| dale_glass wrote:
| That rendition confuses me a lot.
|
| What are they _doing_? Besides being obviously stupid, how is
| anything useful coming out of that? It doesn 't look like
| anybody is actually measuring anything useful.
|
| He's randomly wiggling that screwdriver back and forth, but
| what for? Is somebody collecting data for a table or a graph?
| Shouldn't the separation distance, or angle, or something being
| carefully measured and controlled?
| ortusdux wrote:
| The more you contain the plutonium core within something that
| reflects neutrons, the closer it gets to going critical. In
| this case, they used two half spheres of beryllium as
| reflectors. The screwdriver was used to adjust the amount of
| neutrons reflected, and the results were measurable on a
| Geiger counter. I believe the goal of this technique was to
| compare their calculations to the real thing.
| dale_glass wrote:
| Right, but there's no actual measurement being done, nor it
| could be done, unless there was some guy there measuring
| the separation with calipers or something.
|
| So what's the point, simply to practically demonstrate that
| less distance = more radiation? I guess that makes some
| sense, but it seems too trivial of a thing to demonstrate
| to people in a high level, secret operation.
|
| I'm just imagining that for this to actually produce some
| sort of useful result there needs to be some sort of
| precise measuring happening. Maybe moving half the sphere
| with a screw and having a dial indicator there, or
| something.
| petsfed wrote:
| One of the things I noticed with the experiments I
| participated in was that while the drama was very real _for
| me_ , to an outside observer, its actually kind of dull. To
| keep the pacing tight and keep the audience interested, they
| have to spice it up a bit.
|
| As I understand it, Slotin was demonstrating to another
| colleague how to test the distance dependence of criticality,
| so the data collected was less valuable to the demonstration
| than the procedure. I think the creative license here was the
| second screw driver to make it look more sciencey. Holding
| one half of the beryllium sphere with a bare hand (as was
| part of the approved procedure) probably felt a little too
| slap-dash, and the fact that Slotin's procedure involving a
| screw-driver was unapproved in the first place undermines the
| role of the scene to call out the government's lack of care
| for Cusack's American-everyman character. If there's a
| (tenuous) moral to be extracted from the incident, its that
| Slotin apparently believed in the cowboy persona he
| projected, and it cost him his life.
| petsfed wrote:
| I want to be very clear here that I don't actually think
| there's much moral to this story. They had an idea of how
| bad criticality could be, but there was no real deterrent
| other than Fermi telling Slotin and others that if they
| kept up the procedure, they'd be "dead within a year". That
| tells me that everybody, from Oppenheimer on down, did not
| understand just how dangerous this sort of demonstration
| could be. Given the era, that's pretty understandable.
| russdill wrote:
| During the incident, he was demonstrating the technique
| necessary to Graves, not performing an actual experiment. He
| was a bit of a show-off and was doing the demonstration
| without shims that would have prevented criticality.
|
| And yes, all they had were the counters.
|
| Other than that, the video is really inaccurate.
| ndsipa_pomu wrote:
| I watched the BBC series
| (https://www.imdb.com/title/tt0078037/) a few months ago and
| don't recall any demon core appearances.
| lxgr wrote:
| The experiment setup seems accurate, but sustained (prompt)
| criticality for several seconds, as evidenced by the continuous
| blue glow, wouldn't leave the building standing, let alone any
| surviving witnesses to tell the story, would it?
|
| I thought it was a high-energy pulse over a few milli- or even
| nanoseconds, stopped by thermal expansion of the core or
| reflectors. Oscillation between supercriticality and
| subcriticality seems possible, but that would probably also
| look different.
| jasonwatkinspdx wrote:
| There's been around 60 criticality incidents
| documented/known, none of them resulted in buildings blowing
| up: https://en.wikipedia.org/wiki/Criticality_accident
|
| Criticality isn't the same thing as a deliberate nuclear
| detonation.
| lxgr wrote:
| I appended my comment for a bit more context.
|
| Since the time scale of the exponential term in the
| equation for prompt criticality is on the order of
| nanoseconds, any sustained (i.e. non-oscillating/somehow
| naturally moderated) event, in a configuration as simple as
| a few geometric neutron reflectors, would either be over
| after less than a few of these, or leave a crater, and what
| was pictured in the clip seems sustained to me.
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