It’s funny that scientists actually thought an ice nine type situation had a minuscule but non-zero chance of occurring when they set off the first nuclear bomb: the entire atmosphere would ignite.
https://www.bbc.com/future/article/20210217-the-moments-that...
> They did calculations showing it was impossible
Doesn't mean they couldn't have been surprised by something their calculations didn't take into account. The yield for the Castle Bravo test in the 1950s was 2.5 times what was predicted [0], because some things they didn't take into account turned out to be important (namely that some of the material in the construction of the device would serve as additional fuel to the explosion).
For the first nuclear explosion in 1945, they were initiating an incredibly powerful chain reaction for the first time on Earth. To some extent you just gotta cross your fingers and hope that the chain reaction stops according to your predictions, because you don't know what the "unknown unknowns" are until you try it. The combination of "chain reaction" and "unknown unknowns" is frightening.
Note I said minuscule chance. That would be at the moment of detonating the bomb. If the assessment was earlier, the fact that they had to run calculations proves they considered it as a possibility.
It’s a strong claim to say they proved it couldn’t happen when they didn’t even know the bomb would work for sure.
I’m sure the bbc is hamming it up a bit, but the account of the scientist who freaked out when the bomb worked seems credible.
https://www.bbc.com/future/article/20210217-the-moments-that...
There, a source to back up the original statement. Got one that disproves it?
Some scientists believed it was a minuscule possibility at the time of the test, others didn’t believe it would happen. What was wrong about that statement?
> It is shown that, whatever the temperature to which a section of the atmosphere may be heated, no self-propogating chain of nuclear reactions is likely to be started. The energy losses to radiation always overcompensate the gains due to the reactions.
It then goes on to point out that if considerably more powerful bombs (over 1,000 cubic meters in size) were exploded, then the energy losses to radiation isn't enough .. but that's okay because:
> energy transfer from electrons to light quanta by Compton scattering will provide a further safety factor and will make a chain reaction in air impossible.
That's about as definite as you can be that there would not be a possibility.
Note also the comment "the policy should be adopted of exaggerating the dangers at any point which appears at all questionable."
In the BBC article, "the scientist who freaked out" is the President of Harvard, right? From https://en.wikipedia.org/wiki/James_B._Conant he was a noted PhD chemist who was the chair of the National Defense Research Committee and present as a dignitary. He does not appear to be someone who understood the physics involved.
Additional, the BBC article quotes philosopher Toby Ord as saying "we were creating temperatures unprecedented in Earth's entire history".
This is bunk. Meteor Crater in Arizona had an impact energy of ~10 megatons - https://en.wikipedia.org/wiki/Meteor_Crater . The Chicxulub meteor was about a billion times greater - https://en.wikipedia.org/wiki/Chicxulub_crater#Impact_specif... .
Now, this is total heat, and the quote says "temperature". (Earthquakes release a lot of energy but over a large area, so the temperature isn't hot.)
Cosmic rays regularly hit the earth with much higher temperatures, like https://en.wikipedia.org/wiki/Oh-My-God_particle .
> there also was no evidence that any elected representative was told about the risk
Conant clearly had heard about this risk consideration. Why didn't he tell Roosevelt? Perhaps because no one thought it had even a minuscule chance of being possible?
Now go exhume those hundred their graves and do voodoo witchery go commune with the dead and get every other scientist involved to swear they didn’t entertain that belief. That’s the only way my statement could be shown to be wrong.
Sure the other main guys decided it was impossible but only after running calculations and later bomb tests proved it was not possible but neither of those things are what my comment said so please stop telling me those things.
I didn’t say all scientists or most scientists, I said “scientists” and it’s clear at least one involved scientists considered it a minuscule possibility. If commenters are so adamant at proving me wrong, they’ll have to prove no other scientists involved in the project, of the hundreds, considered it could happen.
https://blogs.scientificamerican.com/cross-check/bethe-telle...
In your source, two sentences after the "less than 1 in 3 million" line, is:
> Dudley’s article provoked an exchange of letters in Bulletin of the Atomic Scientists and a response from Bethe, who said that Buck had “completely misunderstood” Compton and that there was “no chance whatever” that an atomic blast would “ignite the atmosphere.”
and ends with:
> Fear of atmospheric and oceanic ignition is a nightmare with "no relation to reality," he wrote.
Still, let's look at the stated facts.
Here's a copy of Buck's publication - http://large.stanford.edu/courses/2015/ph241/chung1/docs/buc... .
It says the 1 in 3 million calculation was done two years before the test.
Teller and Konopinski's report "Ignition of the Atmosphere With Nuclear Bombs" study, which concluded there was zero possibility, was written "before the first nuclear test at Alamogordo" - http://large.stanford.edu/courses/2015/ph241/chung1/ . Again, this report gives multiple reasons why an atmosphere chain reaction could not happen.
Based on the documents you've identified, it appears there was an early estimate that there might be a problem, but it was low enough for the project to continue. Later, a more detailed analysis shows there was no risk, and the tests occurred.
Recall that pfdietz's comment earlier was "They did calculations showing it was impossible. They would not have done the test if there was any chance that could have happened.".
You strongly asserted this was incorrect, and pointed to document in support of your view.
However, as I've pointed out, the documents appear to strongly support pfdietz's interpretation.
I want to know which involved scientist considered it a non-zero possibility in the last month or so before the Trinity test, after the Teller and Konopinski report had been circulated.
So far you haven't shown any. Conant wasn't involved in the science. Compton certainly was, but the evidence you've presented was from two years previous.
You can't disprove that some of those dead researchers were worried that setting off the bomb would wake dormant kaiju from the seabed. ;)
You agree that due to the consequences they were concerned enough to run the calcs even although they didn’t think it likely and they did this several years before the atomic bomb? For sake of argument, at the time of the bomb no scientist thought it was possible but a couple years before they did run calculations to verify the atmosphere would not ignite when the first bomb test was conducted.
That’s not incompatible with my very first statement. I’m not sure what the point of this debate is?
> "It’s funny that scientists actually thought an ice nine type situation had a minuscule but non-zero chance of occurring when they set off the first nuclear bomb:"
Note the "when they set off the first nuclear bomb".
This is not correct.
That’s this thread.
And my original statement has two reading because the “when” is ambiguous, and only one of those readings would be wrong if the first is assumed wrong for sake of argument.
- you made a short and incorrect comment about timing
- pfdietz at https://news.ycombinator.com/item?id=28434032 made a short comment that you were wrong about the timing. (Note that pfdietz's comment is basically your summary of the thread.)
- you doubled-down by presenting information which you thought supported your viewpoint
- I pointed out that the documents did precisely the opposite
- You tripled down by presenting another document to support your viewpoint
- I pointed out that it still did not do that.
I don't know how "when they set off the first nuclear bomb" can be ambiguous. Had you written "before", yes, but "when"? No.
You also stated "It’s a strong claim to say they proved it couldn’t happen when they didn’t even know the bomb would work for sure.", which is hard to believe because you can read their proof yourself, and it was linked-to in your first reference.
In any case, your sources highlight how contentious this topic has been, which should make you realize how important it is to not being ambiguous about this topic.
That without context doesn’t make any sense.
Adding “when they detonated the first nuclear bomb” tells when the ice nine situation could occur, when the scientists were still thinking that is not actually said.
This whole thread has been about people unhappy that “at one time” was left out as below.
“ It’s funny that [at one time] scientists actually thought an ice nine type situation had a minuscule but non-zero chance of occurring when they set off the first nuclear bomb: the entire atmosphere would ignite.”
Does adding in the implied “at one time” help you see the ambiguity?
Of course a thread will turn contentious when someone bluntly says “ No, they didn't.” when it’s a situation where they aren’t actually wrong about the main point.
Those reply comments come off needlessly aggressive when in reality if they thought the timing was off, the commenter could have said “yeah they did consider that ice nine situation but ruled it out a few years before the first test”. Instead they went on how “no they didn’t, it was impossible because xyz”