New Reality Seeds

[PTTG]

Originally Posted by malloyd

"The Doomsday Device is even more destructive than we thought. Better to let our enemies take the risks of developing it." does seem to have a few logic holes.

I dunno, the contamination of Chicago would be really difficult to deal with but also extremely difficult to reproduce in a way that'll harm the enemy.

[AlexanderHowl]

I agree. I think that the effective destruction of Chicago and the disruptions caused by the mass evacuation of the seven million people in the Chicago metro area (the population of Chicago in 1942 was larger than it is in 2017) would have crippled the US during the height of the war. It could have been damaging enough to have forced the US to withdraw from either the European theater or the Asian theater, allowing either Germany or Japan (depending on the withdraw) to last for a couple more years and possibly give one of them enough time to develop their own atomic bomb.

[ericthered]

Originally Posted by AlexanderHowl

I agree. I think that the effective destruction of Chicago and the disruptions caused by the mass evacuation of the seven million people in the Chicago metro area (the population of Chicago in 1942 was larger than it is in 2017) would have crippled the US during the height of the war. It could have been damaging enough to have forced the US to withdraw from either the European theater or the Asian theater, allowing either Germany or Japan (depending on the withdraw) to last for a couple more years and possibly give one of them enough time to develop their own atomic bomb.

This scenario has never posited the destruction of Chicago. In fact, it explicitly says "the US was not materially harmed". This isn't a nuclear bomb going off, its closer to a reactor meltdown. And at this point in time, people won't know enough to freak out. The radiation hazards won't show up for a while.

[AlexanderHowl]

Are you familiar with the Chernobyl Disaster or the Fukushima Disaster? The equivalent of a reactor meltdown would force the evacuation of everyone within 50 miles (or the deaths of a significant portion of the population within 50 miles by cancer within a year). Either the orderly evacuation causes economic disruptions a few days of the accident or the panicked evacuation a few weeks later when massive numbers of people start dying causes economic disruptions.

[ericthered]

Originally Posted by AlexanderHowl

Are you familiar with the Chernobyl Disaster or the Fukushima Disaster? The equivalent of a reactor meltdown would force the evacuation of everyone within 50 miles (or the deaths of a significant portion of the population within 50 miles by cancer within a year). Either the orderly evacuation causes economic disruptions a few days of the accident or the panicked evacuation a few weeks later when massive numbers of people start dying causes economic disruptions.

Is the chicago pile of comparable size to either of those reactors? And can you get everything in place for a proper reactor meltdown before things go wrong? I've always gotten the impression modern meltdowns are so impressive because we're keep the whole thing going at temperatures and intensities that would normally not be sustainable.

[dcarson]

The radiation threat from Fukushima was so bad that more people died from the evacuation then would have died if they hadn't.

[PTTG]

The pile in my version isn't the same as the real Chicago-Pile-1. The one key thing it has in common is that it had no a active cooling whatsoever. The differences included more highly enriched fuel and that the fuel was inserted all at once rather than gradually as the pile was constructed.

The preliminary changes are left as an exercise to the reader, but rest assured the developers had good reason to make the decisions they did, going by the theory they had. Unfortunately for them, their theories were wrong.

So yes, the nuclear fire was in a way similar to the Chernobyl accident, and those present at the building were likely terminally irradiated, but the actual effects to the city as a whole were merely actuarial and social, rather than widespread death and destruction.

Over the next few years Chicago did empty out as more and more people fled the city because of contamination fears. And there was the fact that nuclear fission had a bad rap from the get-go.

[johndallman]

Originally Posted by PTTG

The differences included more highly enriched fuel

That would be "fuel that is enriched at all." The historical CP-1 ran on natural uranium, which you can do with high-purity graphite as moderator. Having significant quantities of enriched uranium on hand at the end of 1942 requires that development and building of production plant started about two years earlier, which takes some work. If Leo Szilard learns immediately about Frisch and Peierls' critical mass calculation of June 1939, and includes it in the Einstein letter to Roosevelt, you might get somewhere. It requires that an immediate crash program is launched, rather than the slower historical start-up of the Manhattan Project. This is a vast political risk for Roosevelt, since it will be very expensive, and the US is not yet involved with the war.

The preliminary changes are left as an exercise to the reader, but rest assured the developers had good reason to make the decisions they did, going by the theory they had. Unfortunately for them, their theories were wrong.

There wasn't very much theory involved. The fantastic complexities of modern particle physics had not been created. The job was done by measuring half-lives and cross-sections, and calculating from there.

This accident pretty much requires that the thermalized critical mass calculation is way off, and that nobody checked it. Since there were a whole series of critical mass calculations by different groups that gradually brought more and more factors into the problem (it's fairly complicated) this requires them all to be wrong in compatible ways, or for someone to have seized on and promoted a wrong result against credible opposition. Science doesn't really work like that.

[Prince Charon]

Originally Posted by cptbutton

I recall some article about MacArthur which said he refused to arrest Emperor Hirohito unless he got an extra million troops for occupation duty first.

Yeah, while I don't have a high opinion of MacArthur in general (or as a general), he did understand Japanese culture better than most of the rest of the Allied high command at the time.

[PTTG]

Originally Posted by johndallman

That would be "fuel that is enriched at all." The historical CP-1 ran on natural uranium...

Ok, how about this: The fuel was, moments after the piles was assembled, struck by a reality quake that swapped it with enriched uranium from some other timeline.

Everything else was totally as it was in Homeline's history.

That'll really blow some minds in the surviving nuclear science community, since as far as anyone could tell there's no reason at all for this pile to have done that, and yet it did. Follow that up with a decade of checking and triple-checking and witch-hunting.