Before there was any bomb there was the Chicago Pile-1 in the middle of Chicago in a space under the stands at Stagg Field originally built as a rackets court
A wooden frame supported an elliptical-shaped structure, 20 feet high, 6 feet wide at the ends and 25 feet across the middle. It contained 6 short tons of uranium metal, 50 short tons of uranium oxide and 400 short tons of graphite, at an estimated cost of $2.7 million. According to Robert Crease, CP-1 and preceding piles were "the largest unbonded masonry structures since the pyramids.
On December 2, 1942, Fermi announced that the pile had gone critical at 15:25. Fermi switched the scale on the recorder to accommodate the rapidly increasing electric current from the boron trifluoride detector. He wanted to test the control circuits, but after 28 minutes, the alarm bells went off to notify everyone that the neutron flux had passed the preset safety level, and he ordered Zinn to release the zip. The reaction rapidly halted. The pile had run for about 4.5 minutes at about 0.5 watts. Wigner opened a bottle of Chianti, which they drank from paper cups.
The Rhodes book is great on this. Fermi was such a good physicist and a great hands-on engineer. Before electronic calculators or computers: a slide-rule, graphing paper and a notebook. A lot of danger getting the maths wrong! Luckily, Fermi was very good at maths.
That reactor was run at a very low power level, so there was little activity. It was dismantled in 1943 and the parts moved to make CP-2 near Chicago at a site that later became Argonne National Laboratory. CP-2 had shielding (but no cooling) and operated at a few kilowatts.
> Before there was any bomb there was the Chicago Pile-1 in the middle of Chicago in a space under the stands at Stagg Field originally built as a rackets court
Groves's book ("Now It Can Be Told") mentions the people that worked with the graphite bricks, that it got into their skin, and even after an after-work shower, they'd still ooze graphite for hours.
Firstly I wonder what their cover story for their spouses was.
Secondly it's clear that they should've had an on-site sauna. Get some deep cleaning going. That would've flushed the graphite gunk out of their hides.
When the USSR was building the bomb, the director of the graphite manufacturing company unofficially asked Kurchatov (the lead scientist of the Soviet nuclear project) to bring him a handful of diamonds.
He assumed that graphite of such high purity can be useful only for this purpose during the wartime.
From what I can tell, Helion energy has already broken ground on what would be a commercial fusion reactor connected to the WA grid despite their best prototype still not producing net positive energy. It's a gamble, but presumably everyone involved is willing to take the risks. A data center that runs on fusion would be a real watershed moment and everyone wants to be first.
If Helion delivers a working fusion reactor that produces net electricity, at commercially competitive rates, I think that's an even more significant event than the recent AI boom.
> I think it may be a bit of a scam where they keep the investment and their jobs going as long as possible but don't produce power.
There may be some of that, but I think a lot of it is people who believe in what they're doing. A good example in another field is Stockton Rush and his submarine - assuming he wasn't suicidal, he clearly believed in what he was doing, even though to any sane and informed outsider it was fundamentally and life-threateningly flawed.
"Breaking ground" and "wanting to be first" makes no difference to the physics, engineering, and economics involved here. They're just going to end up with an expensive plant that eats money.
No-one has yet demonstrated a break-even fusion reactor purely from a physics perspective - let alone an engineering or, even more challenging, an economics perspective. In other words, we're essentially still in the fundamental physical research phase.
It's like building international airports for jet planes when you've just invented the Kitty Hawk - but worse, really, because at least the Kitty Hawk proved we could fly in practice. With fusion, there's no evidence that we'll ever be able to create a sustained, economically viable reaction.
Normal maps are a good example of tricks in games, why make a watery surface millions of triangles when you can just fake how light reflects off of it and trick people into thinking its got millions of triangles
