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  • the topic today is Alfa Beater Gamma.

  • These air the three first letters of the Greek alphabet.

  • But that's not the topic.

  • The topic is a paper by Alfa Better and GAM Off, which became known as the Alfa Beat.

  • A gamma paper.

  • It's a fairly famous paper is one of those papers.

  • I guess that's sort of less well known than it should be, in the sense that it really uses sort of defining moment in science on.

  • Yet it's mostly known for the fact that it was a rather bad pun, the way the authors were set up than about the scientific content of it.

  • Let me talk to you about Alphas work.

  • He imagined the universe at about three minutes after its inception.

  • He believed that the universe started with a big bang on the particles he knew about.

  • In 1948 were the neutron, which I represent by a life's white neutral thing on a proton, which is black in this picture.

  • So I'm going to imagine there was about seven protons to each neutron in this stage of the universe.

  • After about three minutes, there'll be electrons, but we'll forget about them on there are photons and we'll forget about them.

  • Just concentrate on the protons and neutrons.

  • Now, if a proton neutron get together, they stick and at a certain stage they will hit together very rapidly.

  • On some of them will stick rather like these two coming together.

  • And if I put electrons around, there are maker deuterium atom.

  • If I put electrons around a proton, I'll get a hydrogen atom.

  • So this is the bear, a deuterium.

  • This is the bear hardship.

  • But you haven't got electrons sticking to these because the system is so hot.

  • The system.

  • I mean, the universe is so hot, it's enormously hot.

  • Any electron that would try to get onto this is evaporated away almost instantaneously.

  • So this proton and neutron could get together and make a pair on.

  • Another one could make a pair on these two deuterium nuclei.

  • They could come together and actually they stick together.

  • They make an alpha particle, which is the nucleus of a helium four atom.

  • A helium atom on this pair could join up a cz well on make another helium atom.

  • It was the first time that anyone sort of seriously thought through the consequences of the hot big bang of the university.

  • Start starting in a very hot condensed state on Dhe figured out what that would do in terms of synthesizing the heavier elements, producing elements heavier than hydrogen.

  • So by 17 minutes, all of these neutrons have bound themselves into helium nuclei, and that's all you have left now.

  • Nothing much happens in the universe for the next 350,000 years, by which time the electrons have cooled so much.

  • But it's now possible for electrons, two at a time, to come onto this helium nucleus on make helium atoms on electrons can come onto this proton and make a hygiene atoms.

  • So Alfa came up with the idea that you could calculate the later stage of the universe.

  • How many atoms of each type of form, where the atoms come from, and they're so you, he says, by wait there.

  • It's 1/4 of the universe made up of helium four on by weight that 3/4 of the universe is made of high, and if you look at interstellar space, you find that 3/4 of the universe is made of hygiene and about 1/4 is made of helium was a huge deal.

  • I guess at the time, it sort of wasn't taken terribly seriously because no one really believed in the hot, Big Bang at that point.

  • And so it was really a slightly hypothetical.

  • Well, if the world hot, big bang them, what would the consequences of it be?

  • We're talking now about stuff that was going on in the 1st 3 minutes of the universe stuff that was really telling us how things came together in the early universe to build what we're made up of the elements.

  • So by doing this calculation, are working this out?

  • He was able to show evidence from astronomy, which supported the Big Bang.

  • So the paper said that that a ll the elements could be explained by this process of big bang nuclear synthesis that in these first few seconds of the universe, you could actually make everything away from hydrogen deuterium, helium all the way up to the heavy elements on What we now know is that actually, most of the heavy elements are actually made subsequently in the centers of stars rather than in the big bang itself.

  • This caused a big stir.

  • Ralph Alpher with his supervisor, George Gamow, off who worked together on this project, decided to publish it.

  • Only GAM off had a scent, a wicked sense of humor, which was rather naughty.

  • He decided it would be more fun with Ralph Alpher and George Gamow off to slip in the middle of the name Hans Bethe a with who was his big friend.

  • And then you would have a paper by Alfa Better John Gammell.

  • Alfa Beat a Gamma.

  • The paper has been noted.

  • Alfa Beat a Gamma Heads fourth.

  • It's a little bit of a fraud because, in fact, Hans Bater, the middle author, didn't actually have anything to do with it.

  • He just was a mate of Gandalf's and gambles for.

  • It would be a good joke to put his name down as one of the coffers, but people thought it was funny.

  • All except for Ralph Alfa, who felt really cheated that somebody who did no work got their name on his fundamental piece of work.

  • So he was really rather embittered by the whole thing.

  • So Alfa So this this was his PhD this work.

  • So just to illustrate how ground breaking this this work was and it was realized at the time.

  • Normally, when you defend your paycheck, so you write your PhD on, do you sort of you have to defend it.

  • You have to defend the content to experts in your field.

  • Okay, so in England, typically, for example, you will have a couple of academics that will sort of probe you on the content of your patient.

  • And you have to defend that on.

  • That's about it.

  • There's no one else there.

  • Should you two guys in a room somewhere on Dhe at the end?

  • Hopefully, after maybe four hours or so of 34 hours, you sort of they give you a ticket, he said.

  • Yes, you defended it properly or they don't It's bye bye.

  • And in office case, there were hundreds over 100 people.

  • His PhD defense, the press was there, But he wrote on the paper to the editor Alfa Baster in absentia Gammell on.

  • So it was meant to be a joke on the editors, I think showed the paper to better, and he looked at it, he said.

  • All this is a very amusing title.

  • I like that title.

  • And then he read the paper and thought Well, this is quite good physics.

  • It might even be right.

  • So he scrubbed off the in absentia on DSO.

  • It was partly betters fault for lying that to go ahead, it was quite an entertaining, rather weak kind of pun.

  • There are, You know, there are famous stories about about all the ships of papers.

  • There's a story of somebody who wrote a paper in the first person plural.

  • So we did so and so And it was actually a single off the paper.

  • And you gotta know back from the journal saying you can't do that If you're a single offer, you have to say I and he couldn't be bothered to change all the all the weeds into eyes.

  • So he put his cat down as a co author on the paper.

the topic today is Alfa Beater Gamma.

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B2 中高級

阿爾法-貝塔-伽馬論文--60個符號。 (The Alpha Beta Gamma Paper - Sixty Symbols)

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    林宜悉 發佈於 2021 年 01 月 14 日
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