How the Atomic Bomb Was Made (Part 2)

Hi everyone, welcome to Cold-Knowledge Blind Box. I'm your host, Qiao Yulan. Let's keep talking about how the atomic bomb was built. Let's go back to the tense year of 1939. German scientists had already discovered nuclear fission, and the German army had received orders to start gathering materials for atomic bombs.

At this point, President Roosevelt, only after receiving Einstein's warning letter, took his time and set up an advisory committee to gather American nuclear physicists for a meeting. The meeting reached one conclusion: nuclear fission could be turned into a weapon. And then? Then nothing.

It's said that Einstein was furious when he saw this result. He felt his opinion had not been taken seriously, so he never joined the committee. He also didn't like atomic bomb research himself, believing it would destroy humanity.

But this can't be blamed entirely on Roosevelt, because America had not yet entered the war. To start researching the atomic bomb, you need money, right? To get money, you have to ask the gentlemen in Congress, right? A project like this would burn through at least several billion dollars, and it could still fail. In peacetime, even getting approval to build one more aircraft carrier was a struggle, let alone a project that looked like a bottomless pit.

Leo Szilard, who had co-written the letter with Einstein, and whom we talked about last time as the Hungarian friend who had persuaded Einstein to come to America, didn't give up. Instead, he found the great physicist Fermi, who had also been driven out by Italy's fascist regime. Szilard took charge of raising funds and buying raw materials everywhere, while Fermi buried himself in the lab, working hard to build a nuclear reactor under the name of the advisory committee.

If you think of the atomic bomb as a supercar, and you have no blueprints and no road map, then to build it, the first thing you do is start by researching a two-wheeled bicycle, then gradually add features and keep optimizing through practice. Because the principles of motion are all connected. The only difference is speed and power.

If you think of the atomic bomb as a massively powerful explosive, then this tiny nuclear reactor is a little firecracker. They work on the same principles. First you go from zero to one, and then you calculate what material to use to set off the atomic bomb, and how much mass it needs.

The true power of a bomb lies in control. You have to make sure it survives transport, and that it goes off at the right time and in the right place, so that it shocks the enemy to the greatest extent.

But relying only on scientists and private effort, this matter was, so far, just small-scale tinkering, and it was still very hard to get big results. It wasn't until the attack on Pearl Harbor, when the United States officially entered the war, that the whole nation's war potential was mobilized. Research related to weapons received huge budgets, and this reactor was immediately listed as a national priority project and moved wholesale to a basement at the University of Chicago. The almost unlimited resources also boosted the morale of the scientific team. Finally, in December 1942, it was lit and achieved controlled nuclear fission. That day marked the moment humanity officially stepped into the atomic age.

Since the smallest viable solution had been proven to work, it was time to get started on making the atomic bomb! Roosevelt put the US Army in charge of the whole atomic bomb project. The army said: we're good at fighting wars, but for engineering projects, you really need the engineers. And since the engineering corps headquarters was located in Manhattan, they simply named the project the Manhattan Project.

So they found General Leslie Groves, the engineer in charge of building the Pentagon, and said: "Old Groves, you built the Pentagon so beautifully, you'll surely be able to make an atomic bomb too!" "What? I build houses, so why are you making me work on atomic bombs?"

Because this project, beyond researching nuclear physics, also involved large-scale secret weapons manufacturing. To meet these three requirements, large bases had to be built in several places at once, and run under military management, both to ensure efficiency and to keep it secret. So the overall head had to be an officer who understood engineering.

With an engineering lead in place, they still needed a research lead. Groves looked over the list of nuclear physicists in America and noticed that many of them had fled Europe to escape the war. Although the Hungarian Szilard had contributed greatly, he was, after all, not an American. National security was at stake, so they had to pick an American, ideally someone born under the Stars and Stripes. So who was the American who had brought quantum mechanics back home? That was Oppenheimer.

Oppenheimer was born in New York into a wealthy Jewish family. From childhood he had broad interests and taught himself French and chemistry. He quickly made a name for himself among his peers, and everyone considered him a child prodigy and a genius. Raised amid flowers and applause, he couldn't help growing proud and arrogant, and at the same time he held himself to very strict standards, and tended to feel disgust toward anything he didn't do well.

After finishing his undergraduate degree at Harvard in 1925, he flew to Cambridge in England to continue his studies. At the time, the world's academic center was still in Europe. There, he discovered that what he had learned at Harvard wasn't enough, and he had to make up for a lot of theoretical physics and mathematics. Also, the physics at Cambridge placed great weight on experiments, and that was not Oppenheimer's strength. He learned things very quickly, but his hands-on ability was really weaker, and every time he did an experiment, he would break several test tubes.

Studying in a foreign land, combined with constant setbacks, gave him a serious psychological and mental illness. Fortunately, in 1926 he met Bohr, a great master of quantum mechanics, who came to Cambridge to give an academic talk. Bohr extended an olive branch to him: since you don't like working in the lab, come to Germany and work with me on theory! Oppenheimer wrote happily in his diary: I am very glad to be free of laboratory work. I never did well in the laboratory; others were dissatisfied with me, and I myself was not interested. I felt these things were just forced on me by others.

After getting his PhD in Germany, Oppenheimer returned to teach at the University of California, Berkeley. As a teacher, he was truly excellent. When he taught, he focused purely on theoretical physics, but he would drift off into wide-ranging references, touching on many fields of knowledge. Coming from a wealthy family, he dressed elegantly and often took his students to fine restaurants, and he soon had a band of loyal student fans, who all liked to imitate the way he talked and carried himself.

Groves looked at Oppenheimer's résumé, and in his mind he already had an answer. But there was perhaps one small problem: this guy was a communist sympathizer! Oppenheimer's brother, sister-in-law and lover were all members of the American Communist Party. Although Oppenheimer himself never joined the party, he often helped organize events and donate money. The Soviet Union was an Allied power, but this was still a state secret!

But the situation was urgent, and Groves trusted his own judgment of people. He pushed hard for Oppenheimer to become the research director.

Groves found Oppenheimer and explained the Manhattan Project. Oppenheimer accepted the arrangement quickly, and suggested to Groves that they concentrate their efforts on the big task, rather than letting scientists work separately as the Germans had. How to concentrate? Build a city in the New Mexico desert, where the scientists could bring their families and take care of their daily lives entirely there. That would also solve the secrecy problem at the same time.

Groves agreed to the idea, and immediately led a team of 130,000 people to build a western town in the desert in just a few months. This town is now called the Los Alamos National Laboratory, and it still carries on the development of the US military's cutting-edge weapons.

Oppenheimer was responsible for recruiting the very top scientists in America. But this was not an easy job. Anyone who has worked as management at a big company knows that the bigger the project, the more capable the people it draws, and capable people usually have very big tempers.

During the atomic bomb research, all of America's top scientists were conscripted. Many of them had won Nobel Prizes. Even if you put the famous Einstein in charge of commanding them, they might not all be willing to submit.

Oppenheimer was not yet forty at the time, and he had never won a Nobel Prize. But he spoke eight languages and had a broad base of knowledge. That let him communicate without any barriers with the scientists who had fled from Europe, and he could understand each of their specialties. Even more remarkably, he had expert-level knowledge of chemistry, metallurgy, weapons production, engineering manufacturing and systems engineering management. He also went right to the front-line labs and responded promptly to any need.

As the logistics chief, Groves also did everything he could to meet Oppenheimer's crazy ideas. For example, to build a large cyclotron, they needed a huge magnetic coil about 80 meters in diameter, which required a large amount of copper.

But by then America had already put nearly all its copper reserves into military production. It was really impossible to free up so much pure copper, and the landlord's family had no spare grain either.

So what to do? Oppenheimer said that if there was no pure copper, then pure silver would also work. In terms of physics, silver conducts electricity better than copper.

Silver! But Groves did not hesitate. He immediately had his assistant go to the Treasury Department to negotiate borrowing silver.

The assistant went to Bell, the deputy secretary of the Treasury, and explained his purpose, but refused to disclose what the silver would be used for, stressing only that it was needed for the war.

The Treasury asked how much they needed, and the assistant, Nicholas, answered: 6,000 tons. 6,000 tons? This wasn't cement, it was a precious metal! The Treasury said you probably have no idea how heavy that is, and tried to refuse. But Groves insisted on borrowing the silver. In the end, he got the Treasury to hand over 14,700 tons of silver. Of course, almost all of this silver was later returned to the national treasury. Groves earned only $600 a month, yet every day he had to decide where several million dollars would go.

Thanks to the efficient management of Groves and Oppenheimer, and the efforts of many scientists, just three years later, the first atomic bomb, the "Thin Man," blossomed in the desert. By the way, this explosion permanently changed the wine on Earth.

Grapes absorb carbon dioxide as they grow, and they also absorb carbon isotopes. After 1945, many countries conducted atomic bomb tests, and these atomic explosions caused carbon-14 to appear in the atmosphere for the first time. These elements were absorbed by grapes and ended up in the wine.

These elements are not harmful to the human body, but they can be detected very easily. That's why any wine produced after 1945 will contain this isotope.

Did this little bit of trivia give you chills? Cold-Knowledge Blind Box, see you next time.

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