Now the construction of the "Iceberg aircraft carrier" is nearing completion.

At this time, Churchill was completely immersed in the joy of owning the world's largest warship, and seemed to have forgotten the bitter battle that was taking place on British soil.

And Roosevelt had already heard Churchill's intentions from what he had just said.

Churchill's idea was simple: to move the British political axe to Canada when Britain could no longer hold on, and rely on the colonies to continue to resist.

Seeing Churchill's excitement when he talked about the "Habakuk Project," Roosevelt remembered the "Manhattan Project" of the United States, and couldn't help but sigh in his heart.

Mankind's pursuit of the "ultimate weapon" has remained unchanged since ancient times, but now, he still has no idea whether the United States' ongoing ultimate weapon development program will succeed and what the final effect will be.

He also didn't understand why the silvery-white metal, known as "uranium", could have such magical and powerful power.

Uranium, atomic number 92, silvery-white metal...... It was discovered in 1789 by the German chemist Claprot and named after the newly discovered planet Uranus in 1781. In 1841, the French chemist Pelliro used potassium to reduce uranium tetrafluoride to produce uranium metal for the first time. Uranium is mainly found in bituminous uranium mines, and is abundant in Bohemia and the Belgian Congo. The chemical quality is similar to radium, and it has little industrial use, mainly used for the luminous coating of clocks and watches and the production of ceramics...... This is the 1936 Encyclopædia Britannica about uranium.

More than 10 years before the publication of the 1936 edition of the encyclopedia, Einstein demonstrated the possible surname of "mass-energy conversion", although he did not point out how to achieve this transformation in his paper, but top European physicists and chemists led by Germany are exploring in this direction. In 1932, British scientist Chadwick discovered a new elementary particle when he bombarded beryllium with α particles in a laboratory at the University of Cambridge, and his mentor Rutherford named it neutron. In September 1933, Szilard, a Hungarian-Jewish scientist who was about to go into exile from Europe to the United States, was walking the streets of London when he was inspired by a Rutherford paper published in The Times.

In January 1934, Frederick? Yorio and Irena? The Curies created artificially induced radioisotopes in France by bombarding aluminum with α particles. α particles are positively charged helium nuclei, and their efficiency as nuclear shells depends on the effect of the positive charge they carry themselves, because the negatively charged electrons around the nucleus slow it down, so that the chances of them colliding with a nucleus on the extremely short distance they travel are minimal. On the other hand, if a α particle eventually collides with the nucleus, the repulsive force will also greatly reduce the effect of this collision because both are positively charged. The number of electrons and the number of positive charges in the nucleus are larger in heavier elements, which is why bombarding heavy elements with α particles is ineffective.

A young Italian physicist, Fermi, read about Jorio? After the Curies' research report, it was decided to experiment with neutrons to bombard the nucleus, because neutrons are not charged and are neither attracted to electrons nor repelled by the nucleus. With the support of Italy's Ministry of Health, which provided Fermi with 1 gram of radium, worth 670,000 lire (about $34,000) at the time, he mixed the radioactive gas radon (a natural decay product of radium) with beryllium powder, which bombarded beryllium with α particles released during the decay to produce neutrons. Fermi bombarded various elements with neutrons according to the periodic table, starting with hydrogen and continuing until fluorine produced the first radioactive isotope. In May 1934, when he bombarded uranium element No. 92, he found that it was activated, producing a new element that does not exist in nature, element No. 93, which does not exist on Earth because it is unstable.

On October 22, 1934, Fermi put a silver cylinder containing a radioactive beryllium isotope (neutron source) into paraffin, and the artificially induced radioactivity of the silver isotope was increased by a factor of 100. Fermi believes that when the neutron passes through the paraffin wax, it collides with the proton (hydrogen nucleus) in the paraffin wax and loses part of its kinetic energy, slowing it down, so that Fermi created an important source of artificially induced radiation - slow neutrons.

At this time, several other scientists were doing the same work in Britain and Germany. Szilard's initial experiments in England were beryllium and indium, but these two metals were bombarded by neutrons to no avail, so he turned to some of nature's heaviest elements, actinium, thorium, protactinium and uranium. In 1936, Szilard transferred the patent for the chain reaction to the British Admiralty, and in 1938 he moved to the United States, where he worked at Columbia University.

At the end of 1938, the German physicist Otto? Hahn and Streesmann bombarded the elements thorium-232 and uranium-238 with neutrons in the laboratory of the Kaiser Wilhelm Institute for Physics in Berlin, and achieved incredible results: the nuclei of thorium and uranium bombarded by slow neutrons fissioned, and traces of barium and krypton were detected from the fragments of uranium powder after the bombardment. Since the number of protons of these two elements combined is exactly equal to the number of protons of uranium (92), Hahn speculated that some of the uranium atoms had been blasted into two parts by neutrons. On January 6 and February 10, 1939, Hahn published this phenomenon in the German journal Nature Science.

The dire prospect that the Germans might use nuclear fission and chain reaction militarily worried Bohr, Meitner, Fermi and others. Fermi had pinned his hopes that self-sustaining chain reactions could only be theoretically achieved, because in practice not all neutrons produced by fission could bombard the nuclei of uranium atoms, many would be absorbed, and the neutrons produced by fission were too fast to be effectively used as bullets to bombard atoms unless a way could be found to slow them down.

The challenge of this complex problem led physicists to take immediate action, and Columbia University, Columbia University, and Stanford University all started research in this area, and Columbia University had the advantage because of its cyclotron and leading atomic physicists such as Fermi and Szilard. On January 25, 1939, Fermi's experiments at Columbia University's physics laboratory once again showed that nuclear fission releases enormous energy, and on March 16 of that year, Columbia University physics professor Pegram sent a letter to Admiral Hooper, chief of the U.S. Navy's Ordnance Department, frankly explaining to the military the military the military potential of nuclear fission. Now scientists in the United States are beginning to worry about the fact that Germany is aware of this potential?

In the summer of 1939, Germany abruptly announced a ban on the export of bituminous uranium ore from Bohemia, and European physicists in exile in the United States believed that there was only one possibility for such an approach: Germany had already begun to use uranium for military purposes. These exiled scientists from Germany, Italy, and Hungary understood the political structure and workings of the state of literacy more than their native Americans, and there was a link between research and military applications, especially since most of them had experienced firsthand that all scientific research in Germany could be incorporated into the war effort. This is why Roosevelt could only get warnings from Einstein, Fermi, Szilard, and others. These are men who understand military literacy and the concentration of power, while most American-born scientists have never found their way out of the ivory towers of academia.

In July of that year, two Hungarians in exile, Szilard and Wegener, visited Einstein at Princeton University, and the three decided to draft a letter to Roosevelt, reminding him of the possibility of the Germans developing an atomic bomb, and to sign it by Einstein, the most famous scientist in the United States. Einstein carefully read the two densely written typewriter sheets of paper and finally commented: "This will be the first time in human history that energy not from the sun has been utilized", and then signed it under the second page. Neither of these men was an expert on diplomacy and was not at all sure that Roosevelt would be able to read the letter, so Seelard persuaded Einstein to send it to his old friend, Queen Elisabeth of Belgium, through whom he forwarded it to Roosevelt, and sent a copy to the U.S. State Department. A few days later, a friend of Sylard's came up with a better idea and gave the letter to Wall Street financier Alexander? Sachs, who was Roosevelt's economic adviser, had the opportunity to meet directly with the president.

On October 11, Sachs handed Roosevelt Einstein's letter, but the two pages were too long for Roosevelt to listen to half of them, so he sent Saxophone to see him again. The next morning, Sachs told Roosevelt the story of Napoleon's refusal to use the newly invented steamship and his failure to conquer Britain, impressing the president. In his reply, Roosevelt told Einstein that he felt "the situation was so important that I set up a committee,...... Let it fully demonstrate the viability of the suggestion you made to mention uranium. ”

However, the "committee" (or "Uranium Advisory Committee") was formed at any pace: hearing testimony, requesting a budget, reviewing reports, convening committee meetings, organizing, reshuffling the board of directors, and directing changes...... It was not until two years later, on December 6, 1941, that the committee received a message from the Director of the General Administration for Scientific Research and Development (OSRD) and the director of the Carnegie Academy, Van Nival? Bush's decision to "go all out for atomic energy research."

Since then, the United States has begun work on the development of the "ultimate weapon".

And now, more than two years have passed, and what Einstein called a "powerful bomb" still has not appeared.

Now Roosevelt, because of the disadvantage of the Allied war, the desire for the possession of such weapons has become more and more intense.

But Roosevelt did not know that at this time, China was already ahead of the United States and Germany in the development of the "ultimate weapon".

Taklamakan Desert, Gobi Desert.

A young Chinese army officer sitting in a car, looking at the endless desert, was writing something quickly with a pen in a notebook. As he wrote, the corners of his mouth couldn't help but smile.

“…… Seeing this vast desert, I couldn't help but think of her, and suddenly understood that it was in this place that she spent her youth. Her name is Yang Lanyu - it is said that she is the daughter of President Yang Da. That's all she told me with her black grape-like eyes. But I can't read it, I look like a stupid spy in front of the 'top state secret', who wants to know everything, but is not good at capturing any information. Even more stupid than me is Wu Xinwei, who actually thinks that 'Yang Lanyu is dishonest'. And Yang Lanyu's alienation from him is precisely because she must be 'dishonest'. The 'dishonest' woman may be the most trustworthy woman we have ever fantasized about. ”

"A silvery-white ball, about a meter in diameter, with an antenna-like braid standing straight at the top. It is supported by a silver-white triangular metal frame, reflecting the scenery in the sky in the open grassland: the clouds are rolling and the wind is soothing, and the moon is setting. At a distance of 25 meters from it, it is a concealed unit for control and observation. The one-and-a-half-meter-thick iron wall was scarred and stained, like the bark of a tree that had been eroded by the wind and rain over the years. ”

"My friend who accompanied me said that this is the No. 216 Factory, referred to as the shooting range, which is specially used for detonation tests. Two detonation tests of nuclear weapons and tests of the penetration and power of armor-piercing shells were carried out here. All simulated explosions and cold tests are done here. ”

"I don't know if Yang Lanyu works in Factory 216, but I hope she is here often. This is the frontier of Chinese scientists turning the inscrutable atomic theory into weapons, and it is the place where physics evolves into objects, chemistry focuses on energy, and mathematics creates power. I often imagine that Yang Lanyu pressed the last light button with her slender index finger accurately, or that it was she who made a crisp sound in the first ten seconds of the explosion zero: '9, 8, 7, 6, 5, 4, 3, 2, 1, detonate. Or maybe she's in charge of the testing instruments, measuring the physical effects of steel, cement, wood, and so on, as well as biological and chemical effects. Or perhaps her role is more important - she is an obscure 'secret developer', a young female scientist who works with many of our country's outstanding scientists, and she should have seen more than once in the observation hole the colored smoke after the success of the experiment and the gray silence after the failure. Her joys and sorrows, like those of all scientists, are entirely dominated by a silvery-white sphere about a meter in diameter. Even I hope that she made it all by herself, just like a hen hatching eggs, because of her long-lasting warmth, in the land of China, there is finally the sound of nuclear weapons. ”

"The first time I met Yang Lanyu was in the winter of 1941, when I, as a reporter of Qinghai Daily, and Wu Xinwei, as a reporter of the provincial radio station, went to Haiyan County for interviews. The train carriage is like a cold storage for the movement, unheated, cold to the bone, and the fur coat is wrapped around the body, like wearing a thin shirt, light and fluttering. I wanted to warm myself up with a cup of boiling water, and after walking through seven carriages and not seeing a boiler room with boiling water, I asked the conductor, who said, 'We don't supply boiling water. ’”

"Suddenly, everything changed – it wasn't cold, I didn't want to drink boiled water, I didn't even feel like winter anymore. Wu Xinwei later told me that his only thought at this time was to take off his fur coat and give it to her. She appeared, and Yang Lanyu appeared. She stamped her feet in the aisle of the carriage, and the pretty girl stamped her feet back and forth in the aisle of the carriage. The movement of her feet attracted Wu Xinwei, who found that her feet looked good, even though she was wearing suede shoes. Looking up from her feet, the more she looks at it, the better she looks, even if she is wearing a cotton jacket, the curves that can't be straightened make her waist and hips beautiful again and again; Further up, there are the eyes. Like all lovers who fall in love at first sight, Wu Xinwei believes that this is the most beautiful eye he has ever seen in his life, very abstract, very conceptual, but so bright that it moves him. And I got the impression that they were not abstract, they were two large, round black grapes, suspended in the best places in your field of vision in the dry and cold plateau. What could make you think of water spirits more than the black grapes in the desert? ”

Wu Xinwei finally didn't have the courage to take off her coat and give it to her. He knew that too abrupt help would make a girl with a different surname feel nervous and flatly refuse. He is like a male bird, a stag and instinctively realizes that the most important thing is to get the attention of the other person in the first place. He began to sing, in a rich baritone voice along with the radio - "In That Far Away Place". ”

"I didn't understand why the same song was played endlessly on the train and on the radio that day: "In That Far Away Place". Wu Xinwei sang along over and over again, her voice getting louder and louder. Many people in the carriage were watching him, and the girl naturally noticed him. He seemed to be very proud, and as soon as he was proud, he sang the wrong words, and sang 'I want her to hold the thin leather whip' to 'look at the thin leather whip every day.' Someone shouted at him, 'What are you doing with the whip?' The whole car laughed - who wouldn't sing this song? He actually sang it wrong. The girl didn't laugh, she left the aisle of the carriage and took the seat that was vacant from us. Wu Xinwei's singing came to an abrupt end. ”

He must have been frustrated: the love song had sung the girl and had gone behind a high chair. But only two minutes later, Wu Xinwei's voice sounded again. He asked me: 'Do you think 'In That Far Away Place' is a Tibetan folk song or a Kazakh folk song?' I said, 'I don't know.' Wu Xinwei said: "Let me tell you, there are four signatures for this song, one is a Tibetan folk song, the second is a Kazakh folk song, the third is a Qinghai folk song, and the fourth is a northwest folk song, but I think it is a Tibetan folk song from Qinghai in the northwest." ”

(To be continued)