The 100-Year-Old Man Who Climbed Out the Window and Disappeared

unlocking the power that held the nuclei of atoms together, trying to create more enormous explosions than anything the world had seen before.
    By April 1945, they were almost there. The researchers – and for that matter Allan – knew how to achieve a nuclear reaction, but they didn’t know how to control it. The problem fascinated Allan, and when he sat in the library in the evenings he worried away at the problem that nobody had asked him to worry about – and he solved it.
    Every week that spring, the most important military people met for hours with the leading physicists, led by chief scientist J. Robert Oppenheimer, while Allan filled their coffee cups – and listened.
    The scientists pulled at their hair and asked Allan for more coffee. The military people scratched their heads and asked Allan for more coffee. The military people and the scientists all despaired of finding a solution and asked Allan for more coffee. And so it went on, week after week. Allan had been sitting on the solution to the group’s problem for some time but he didn’t think it was the waiter’s task to tell the chef how to prepare dinner, so he kept what he knew to himself.
    Until on one occasion, to his own surprise, he heard himself say:
    ‘Excuse me, but why don’t you divide the uranium into two equal parts?’
    It just sort of slipped out, while he was pouring coffee into Robert Oppenheimer’s cup.
    ‘ What did you say?’ said Oppenheimer, who was so shocked that the waiter had opened his mouth that he hadn’t even listened to what Allan said.
    Allan had no choice but to go on.
    ‘Well, if you divide the uranium into two equal parts and slap them together only when it is time, then they’ll explode when you want them to.’
    ‘ Equal parts?’ said Oppenheimer. There was a lot more going on in his head at that moment, but ‘equal parts’ was what he managed to say.
    ‘Well, perhaps you have a point there, professor. The parts don’t have to be equal in size, the important thing is that they are big enough when they come together.’
    Lieutenant Lewis, who had vouched for Allan’s suitability as an assistant, looked as if he wanted to murder the Swede, but one of the scientists around the table reacted with considerable interest:
    ‘But how do we slap them together? And when? In the air?’
    ‘Exactly, professor. You see, it’s not hard to make it all explode. The problem is that you can’t control the moment of explosion. But a critical mass divided into two gives you two un critical masses, doesn’t it? And the opposite applies too, because from two uncritical masses you can get one critical mass.’
    ‘And how do you propose we slap them together, Mr… excuse me, but who are you?’ said Oppenheimer.
    ‘I’m Allan,’ said Allan.
    ‘And, Mr Allan, how do we slap them together?’
    ‘With a good old, everyday explosive charge,’ said Allan. ‘That’s the sort of thing I’m good at, but I am sure you can manage it yourselves.’
    Professors of Physics in general and top military scientists in particular are not stupid. In a few seconds, Oppenheimer had worked his way through thickets of equations and come to the conclusion that it was extremely likely that the waiter was right. Just imagine that something so complicated could have such a simple solution! A good old everyday explosive charge at theback of the bomb could be activated from a distance and would send an uncritical mass of uranium-235 forwards to a meeting with another uncritical mass. It would immediately become critical. The neutrons would start to move, the uranium atoms would start to split. The chain reaction would be in process and…
    ‘Bang!’ said Oppenheimer to himself.
    ‘Exactly,’ said Allan. ‘I see that you have already worked it out, professor. Would anyone like some more coffee?’
    At that very moment the door to the secret room was opened and in walked Vice President Truman on one of his rare and always unannounced visits.
    ‘Sit down,’ said the vice president to the men, who were all standing to attention.
    To be on the safe side, even Allan sat down. If a vice president told you to sit down then it was probably best to sit down, that was how it worked in America, he thought.
    The vice president asked for a status report from Oppenheimer, who quickly stood up again. Somewhat flustered, the only thing he could think to say was that Mr Allan over there in the corner had just solved the remaining problem of