How to Make an Apple Pie from Scratch (Harry Cliff)

And there are some really big questions that we need answers to. Our current theory of what the world is made from down at the fundamental level is known as the “standard model” of particle physics—a deceptively boring name for one of humankind’s greatest intellectual achievements. Developed over decades through the combined efforts of thousands of theorists and experimentalists, the standard model says that everything we see around us—galaxies, stars, planets, and people—is made of just a few different types of particles, which are bound together inside atoms and molecules by a small number of fundamental forces. It’s a theory that explains everything from why the Sun shines to what light is and why stuff has mass. What’s more, it’s passed every experimental test we’ve been able to throw at it for almost half a century. It is, without a doubt, the most successful scientific theory ever written down.
All that said, we know that the standard model is wrong, or at the very least seriously incomplete. When it comes to the deepest mysteries facing modern physics, the standard model simply shrugs or offers up a bunch of contradictions instead of answers. Take this for starters. After decades of painstakingly peering into the heavens, astronomers and cosmologists are pretty well convinced that 95 percent of the universe is made of two invisible substances known as “dark energy” and “dark matter.” Whatever they are—and to be clear we haven’t got much of a clue about either of them—they’re definitely not made from any of the particles in the standard model. And as if missing 95 percent of everything wasn’t bad enough, the standard model also makes the rather startling assertion that all the matter in existence should have been wiped out in a cataclysmic annihilation with antimatter in the first microsecond of the big bang, leaving a universe with no stars, no planets, and no us.
So it’s pretty obvious that we are missing something big, most likely in the form of some as-yet-undiscovered fundamental particles that could help explain why the universe is the way it is.

10 thoughts on “How to Make an Apple Pie from Scratch (Harry Cliff)

  1. shinichi Post author

    How to Make an Apple Pie from Scratch: In Search of the Recipe for Our Universe, from the Origins of Atoms to the Big Bang

    by Harry Cliff

    Carl Sagan once quipped, “If you wish to make an apple pie from scratch, you must first invent the universe.” But finding the ultimate recipe for apple pie means answering some big questions: What is matter really made of? How did it escape annihilation in the fearsome heat of the Big Bang? And will we ever be able to understand the very first moments of our universe?

    In How to Make an Apple Pie from Scratch, Harry Cliff—a University of Cambridge particle physicist and researcher on the Large Hadron Collider—sets out in pursuit of answers. He ventures to the largest underground research facility in the world, deep beneath Italy’s Gran Sasso mountains, where scientists gaze into the heart of the Sun using the most elusive of particles, the ghostly neutrino. He visits CERN in Switzerland to explore the “Antimatter Factory,” where the stuff of science fiction is manufactured daily (and we’re close to knowing whether it falls up). And he reveals what the latest data from the Large Hadron Collider may be telling us about the fundamental nature of matter.

    Along the way, Cliff illuminates the history of physics, chemistry, and astronomy that brought us to our present understanding—and misunderstandings—of the world, while offering readers a front-row seat to one of the most dramatic intellectual journeys human beings have ever embarked on.

    A transfixing deep dive into the origins of our world, How to Make an Apple Pie from Scratch examines not just the makeup of our universe, but the awe-inspiring, improbable fact that it exists at all.

  2. shinichi Post author

    物質は何からできているのか アップルパイのレシピから素粒子を考えてみた

    by ハリー クリフ

    translated by 熊谷 玲美

     本書は、かつてカール・セーガンがいった「アップルパイをゼロから作りたかったら、まず宇宙を発明しなければなりません」の発言に沿って話が進む。そうであれば、実際にそのアップルパイの究極のレシピを見つけるには、いくつかの大きな疑問に答えなければならない。たとえば物質は本当は何からできているのか? 物質はビッグバンのものすごい熱さの中でどうやって消滅を免れたのか? そして、宇宙の最初の瞬間を理解することは可能だろうか? 本書はそうした疑問から書かれている。たとえば物質とは何でできているのか。この本の流れに沿うなら、アップルパイはリンゴと小麦粉と砂糖と・・・となる。しかしその1つひとつはさらに何からできているのだろうか。小さなものが見えなかった時代、見る方法が生まれつつある時代、そして現代まで、人々は物質が何からできているのかをどう考え、どのようにそれを見いだす方法論を構築し、見誤ったり、勘違いしたりの繰り返しから、事実を見つけてきたのか。その変遷をたどりながら、TEDトーク(Have We Reached the End of Physics?)で250万回視聴された著者(CERNのLHCで研究に携わる)が素粒子とはどのようなものかを語る。


     弦理論の問題点とは? 自然の基本法則を完全に理解できるのか? スファレロンとは何か? ヒッグス粒子どうやって見つかったか? ヒッグス場とは何か? 反物質はどうやって作るのか? 超対称性とは何か? などこの分野の最新の成果を盛り込みつつ、素粒子物理学というとっつきにくい内容を、身近な物質とその成分の発見の歴史をとおして、肉眼世界からミクロの世界へと、最新の研究成果をわかりやすく語っていく。ちなみに素粒子物理学は宇宙の基本的物質の探求(ニュートリノの反粒子の研究など、ノーベル賞の小柴さんや梶田さんが関連する研究)や、その終わりにかかわるダークマターやダークエネルギーなどの最新の宇宙研究にもつながっていることがわかる。

  3. shinichi Post author

    … glory days of physics were over, the quantum revolution was done, and the time wasn’t yet ripe for new breakthroughs. If the ambitious young man wanted to make his mark on science, he should look elsewhere. So Fred Hoyle turned his attention to the stars. During his long and eclectic career, Hoyle became famous for his contrarian, sometimes wacky scientific views, bitter disputes with fellow academics, and as a talented writer of science fiction, including the smash-hit BBC television series A for Andromeda. Today, he’s probably best known as a die-hard opponent of the big bang theory, which he dismissed as pseudoscience thanks to its inability to explain what actually caused it to happen in the first place.

  4. shinichi Post author

    Have we reached the end of physics?

    Harry Cliff

    Why is there something rather than nothing? Why does so much interesting stuff exist in the universe? Particle physicist Harry Cliff works on the Large Hadron Collider at CERN, and he has some potentially bad news for people who seek answers to these questions. Despite the best efforts of scientists (and the help of the biggest machine on the planet), we may never be able to explain all the weird features of nature. Is this the end of physics? Learn more in this fascinating talk about the latest research into the secret structure of the universe.


    A hundred years ago this month, a 36-year-old Albert Einstein stood up in front of the Prussian Academy of Sciences in Berlin to present a radical new theory of space, time and gravity: the general theory of relativity.

    General relativity is unquestionably Einstein’s masterpiece, a theory which reveals the workings of the universe at the grandest scales, capturing in one beautiful line of algebra everything from why apples fall from trees to the beginning of time and space.

    1915 must have been an exciting year to be a physicist. Two new ideas were turning the subject on its head. One was Einstein’s theory of relativity, the other was arguably even more revolutionary: quantum mechanics, a mind-meltingly strange yet stunningly successful new way of understanding the microworld, the world of atoms and particles.

    Over the last century, these two ideas have utterly transformed our understanding of the universe. It’s thanks to relativity and quantum mechanics that we’ve learned what the universe is made from, how it began and how it continues to evolve. A hundred years on, we now find ourselves at another turning point in physics, but what’s at stake now is rather different. The next few years may tell us whether we’ll be able to continue to increase our understanding of nature, or whether maybe for the first time in the history of science, we could be facing questions that we cannot answer, not because we don’t have the brains or technology, but because the laws of physics themselves forbid it.

    This is the essential problem: the universe is far, far too interesting. Relativity and quantum mechanics appear to suggest that the universe should be a boring place. It should be dark, lethal and lifeless. But when we look around us, we see we live in a universe full of interesting stuff, full of stars, planets, trees, squirrels. The question is, ultimately, why does all this interesting stuff exist? Why is there something rather than nothing? This contradiction is the most pressing problem in fundamental physics, and in the next few years, we may find out whether we’ll ever be able to solve it.

    At the heart of this problem are two numbers, two extremely dangerous numbers. These are properties of the universe that we can measure, and they’re extremely dangerous because if they were different, even by a tiny bit, then the universe as we know it would not exist. The first of these numbers is associated with the discovery that was made a few kilometers from this hall, at CERN, home of this machine, the largest scientific device ever built by the human race, the Large Hadron Collider. The LHC whizzes subatomic particles around a 27-kilometer ring, getting them closer and closer to the speed of light before smashing them into each other inside gigantic particle detectors. On July 4, 2012, physicists at CERN announced to the world that they’d spotted a new fundamental particle being created at the violent collisions at the LHC: the Higgs boson.

    Now, if you followed the news at the time, you’ll have seen a lot of physicists getting very excited indeed, and you’d be forgiven for thinking we get that way every time we discover a new particle. Well, that is kind of true, but the Higgs boson is particularly special. We all got so excited because finding the Higgs proves the existence of a cosmic energy field. Now, you may have trouble imagining an energy field, but we’ve all experienced one. If you’ve ever held a magnet close to a piece of metal and felt a force pulling across that gap, then you’ve felt the effect of a field. And the Higgs field is a little bit like a magnetic field, except it has a constant value everywhere. It’s all around us right now. We can’t see it or touch it, but if it wasn’t there, we would not exist. The Higgs field gives mass to the fundamental particles that we’re made from. If it wasn’t there, those particles would have no mass, and no atoms could form and there would be no us.

    But there is something deeply mysterious about the Higgs field. Relativity and quantum mechanics tell us that it has two natural settings, a bit like a light switch. It should either be off, so that it has a zero value everywhere in space, or it should be on so it has an absolutely enormous value. In both of these scenarios, atoms could not exist, and therefore all the other interesting stuff that we see around us in the universe would not exist. In reality, the Higgs field is just slightly on, not zero but 10,000 trillion times weaker than its fully on value, a bit like a light switch that’s got stuck just before the off position. And this value is crucial. If it were a tiny bit different, then there would be no physical structure in the universe.

    So this is the first of our dangerous numbers, the strength of the Higgs field. Theorists have spent decades trying to understand why it has this very peculiarly fine-tuned number, and they’ve come up with a number of possible explanations. They have sexy-sounding names like “supersymmetry” or “large extra dimensions.” I’m not going to go into the details of these ideas now, but the key point is this: if any of them explained this weirdly fine-tuned value of the Higgs field, then we should see new particles being created at the LHC along with the Higgs boson. So far, though, we’ve not seen any sign of them.

    But there’s actually an even worse example of this kind of fine-tuning of a dangerous number, and this time it comes from the other end of the scale, from studying the universe at vast distances. One of the most important consequences of Einstein’s general theory of relativity was the discovery that the universe began as a rapid expansion of space and time 13.8 billion years ago, the Big Bang. Now, according to early versions of the Big Bang theory, the universe has been expanding ever since with gravity gradually putting the brakes on that expansion. But in 1998, astronomers made the stunning discovery that the expansion of the universe is actually speeding up. The universe is getting bigger and bigger faster and faster driven by a mysterious repulsive force called dark energy.

    Now, whenever you hear the word “dark” in physics, you should get very suspicious because it probably means we don’t know what we’re talking about.

    We don’t know what dark energy is, but the best idea is that it’s the energy of empty space itself, the energy of the vacuum. Now, if you use good old quantum mechanics to work out how strong dark energy should be, you get an absolutely astonishing result. You find that dark energy should be 10 to the power of 120 times stronger than the value we observe from astronomy. That’s one with 120 zeroes after it. This is a number so mind-bogglingly huge that it’s impossible to get your head around. We often use the word “astronomical” when we’re talking about big numbers. Well, even that one won’t do here. This number is bigger than any number in astronomy. It’s a thousand trillion trillion trillion times bigger than the number of atoms in the entire universe.

    So that’s a pretty bad prediction. In fact, it’s been called the worst prediction in physics, and this is more than just a theoretical curiosity. If dark energy were anywhere near this strong, then the universe would have been torn apart, stars and galaxies could not form, and we would not be here. So this is the second of those dangerous numbers, the strength of dark energy, and explaining it requires an even more fantastic level of fine-tuning than we saw for the Higgs field. But unlike the Higgs field, this number has no known explanation.

    The hope was that a complete combination of Einstein’s general theory of relativity, which is the theory of the universe at grand scales, with quantum mechanics, the theory of the universe at small scales, might provide a solution. Einstein himself spent most of his later years on a futile search for a unified theory of physics, and physicists have kept at it ever since.

    One of the most promising candidates for a unified theory is string theory, and the essential idea is, if you could zoom in on the fundamental particles that make up our world, you’d see actually that they’re not particles at all, but tiny vibrating strings of energy, with each frequency of vibration corresponding to a different particle, a bit like musical notes on a guitar string.

    So it’s a rather elegant, almost poetic way of looking at the world, but it has one catastrophic problem. It turns out that string theory isn’t one theory at all, but a whole collection of theories. It’s been estimated, in fact, that there are 10 to the 500 different versions of string theory. Each one would describe a different universe with different laws of physics. Now, critics say this makes string theory unscientific. You can’t disprove the theory. But others actually turned this on its head and said, well, maybe this apparent failure is string theory’s greatest triumph. What if all of these 10 to the 500 different possible universes actually exist out there somewhere in some grand multiverse? Suddenly we can understand the weirdly fine-tuned values of these two dangerous numbers. In most of the multiverse, dark energy is so strong that the universe gets torn apart, or the Higgs field is so weak that no atoms can form. We live in one of the places in the multiverse where the two numbers are just right. We live in a Goldilocks universe.

    Now, this idea is extremely controversial, and it’s easy to see why. If we follow this line of thinking, then we will never be able to answer the question, “Why is there something rather than nothing?” In most of the multiverse, there is nothing, and we live in one of the few places where the laws of physics allow there to be something. Even worse, we can’t test the idea of the multiverse. We can’t access these other universes, so there’s no way of knowing whether they’re there or not.

    So we’re in an extremely frustrating position. That doesn’t mean the multiverse doesn’t exist. There are other planets, other stars, other galaxies, so why not other universes? The problem is, it’s unlikely we’ll ever know for sure. Now, the idea of the multiverse has been around for a while, but in the last few years, we’ve started to get the first solid hints that this line of reasoning may get born out. Despite high hopes for the first run of the LHC, what we were looking for there — we were looking for new theories of physics: supersymmetry or large extra dimensions that could explain this weirdly fine-tuned value of the Higgs field. But despite high hopes, the LHC revealed a barren subatomic wilderness populated only by a lonely Higgs boson. My experiment published paper after paper where we glumly had to conclude that we saw no signs of new physics.

    The stakes now could not be higher. This summer, the LHC began its second phase of operation with an energy almost double what we achieved in the first run. What particle physicists are all desperately hoping for are signs of new particles, micro black holes, or maybe something totally unexpected emerging from the violent collisions at the Large Hadron Collider. If so, then we can continue this long journey that began 100 years ago with Albert Einstein towards an ever deeper understanding of the laws of nature.

    But if, in two or three years’ time, when the LHC switches off again for a second long shutdown, we’ve found nothing but the Higgs boson, then we may be entering a new era in physics: an era where there are weird features of the universe that we cannot explain; an era where we have hints that we live in a multiverse that lies frustratingly forever beyond our reach; an era where we will never be able to answer the question, “Why is there something rather than nothing?”

    Thank you.

    Bruno Giussani: Harry, even if you just said the science may not have some answers, I would like to ask you a couple of questions, and the first is: building something like the LHC is a generational project. I just mentioned, introducing you, that we live in a short-term world. How do you think so long term, projecting yourself out a generation when building something like this?

    Harry Cliff: I was very lucky that I joined the experiment I work on at the LHC in 2008, just as we were switching on, and there are people in my research group who have been working on it for three decades, their entire careers on one machine. So I think the first conversations about the LHC were in 1976, and you start planning the machine without the technology that you know you’re going to need to be able to build it. So the computing power did not exist in the early ’90s when design work began in earnest. One of the big detectors which record these collisions, they didn’t think there was technology that could withstand the radiation that would be created in the LHC, so there was basically a lump of lead in the middle of this object with some detectors around the outside, but subsequently we have developed technology. So you have to rely on people’s ingenuity, that they will solve the problems, but it may be a decade or more down the line.

    BG: China just announced two or three weeks ago that they intend to build a supercollider twice the size of the LHC. I was wondering how you and your colleagues welcome the news.

    HC: Size isn’t everything, Bruno. BG: I’m sure. I’m sure.
    It sounds funny for a particle physicist to say that. But I mean, seriously, it’s great news. So building a machine like the LHC requires countries from all over the world to pool their resources. No one nation can afford to build a machine this large, apart from maybe China, because they can mobilize huge amounts of resources, manpower and money to build machines like this. So it’s only a good thing. What they’re really planning to do is to build a machine that will study the Higgs boson in detail and could give us some clues as to whether these new ideas, like supersymmetry, are really out there, so it’s great news for physics, I think.

  5. shinichi Post author



    『How to Make an Apple Pie from Scratch』
    Harry Cliff 著、Doubleday、2021年刊

    私たちは何でできているのか? 私たちのまわりのものは何でできているのか? 人はそんなことを、ずっと昔から考え、説明してきた。魂とか肉体とか、こころとかからだとか、神とか自然とか、あの世とかこの世とか、天国とか地獄とか、天使とか悪魔とか、霊だとかいったものが、宗教とか学問とか政治とか芸術とか言い伝えとかのなかに現れ、そして消えていった。

    ここ何百年かは、真実と神という言葉が少しだけ後退し、事実を科学で探ることが主流になってきた。医学が変わり解剖技術が発達すると、センチメートルやミリメートルの世界のことがわかるようになり、脳とか 肺とか 心臓とか 胃腸とか 肝臓とか 膵臓とか 脾臓とか 腎臓とかの臓器とかが明瞭に説明されるようになる。

    さらに、光学顕微鏡が発達したことで、マイクロメートルの世界のことまでがよくわかるようになり、細上皮とか 内皮とか 膜とか 管とかの区分けが進み、それぞれが 上皮細胞とか 内皮細胞とかいった細胞でできているという説明がついていった。

    そして、電子顕微鏡が発達するようになると、ナノメートルの世界のことまでがわかるようになり、細胞のなかには 細胞核だとか 細胞膜だとか 細胞質だとかがあって、細胞核には 遺伝情報であるDNAやRNAやタンパク質が含まれているとか、DNAもRNAも糖と核酸と塩基でできているとかということを言うようになった。

    「糖は 水素と酸素と炭素、核酸は 水素と酸素とリン、塩基は 水素と酸素と窒素 で出来ている。タンパク質はアルギニン グルタミンといった20種類のアミノ酸で出来ていて、アミノ酸は 炭素と水素と酸素と窒素と硫黄で出来ている」などという説明を聞くようになって、私たちは宗教を捨て、科学を信じるようになった。

    分子レベルで考えると、人間はその60%が水、12%~20が脂質、15%がタンパク質といわれている。元素レベルで考えると、水が水素と酸素でできていることもあって、酸素が61%、炭素が23%、水素が10%、窒素が2.6% で、その他に カルシウムが1.4%、リンが1.1%、硫黄が0.2%、カリウムが0.2%、ナトリウムが0.14%、塩素が0.12%、マグネシウムが0.027% と書いてあるけれど、本当かどうかは、自分のからだを見ても触っても、わからない。もはや、科学は信じるものなのだ。

    地球の大気や海水のことを調べてみると、大気は、78%が窒素、21%が酸素、そして 0.93%がアルゴン、海水は、酸素が85.9%、水素が10.7%、そして塩分が3.4%。私たちの体が、空気と水の主要元素である酸素、水素、窒素でできているのは、決して偶然ではない。そして炭素。炭素が、糖、タンパク質、脂質、DNA、筋肉など、体内のほぼすべてのものの主成分だというのも、たぶん偶然ではない。私たちがこの地球の一部なのだという思いが、改めて強くなる。






    例えば水素の原子という単純なものでさえ、誰にも想像ができない。長さが10-14 m(大きさが10-42 m3)の原子核と、そのまわりを動き回る長さが10-15 m(大きさが10-45 m3)のたったひとつの電子とが、長さが10-10 m(大きさが10-30 m3)の原子をかたちづくっている。これは、細菌のまわりをたった一つのウイルスが動き回ってピンポン玉をかたちづくっているようなものだ。こんな不思議なことを、どう理解すればいいのか?

    そもそも原子はどんなものなのか? 昔の教科書に載っていた「原子核のまわりを電子が回るモデル」は正確ではない。電子に存在するある場所があるわけではなく、電子雲と呼ばれる存在する可能性がある場所があるだけ。存在する確率が高いほど雲は密になる。私たちが知っている世界とは違う量子力学の世界は、不思議なことばかり。わからないのがあたりまえではないか。




    宇宙はダークマター(Dark Matter)とダークエネルギー(Dark Energy)とでできていると誰もが言うけれど、それが仮説の上に成り立っている物語だと知る人は少ない。存在が想定され、間接的に存在を示唆する観測事実はあるけれど、直接的な観測例はない。そんな正体不明のものを信じるのだから、科学はもはや宗教と同じになってしまっている。「わくわく」を感じられないのだ。

    今週は、そんな物理学の現状を整理する一冊。『How to Make an Apple Pie from Scratch』(Harry Cliff 著、Doubleday、2021年刊)だ。『In Search of the Recipe for Our Universe, from the Origins of Atoms to the Big Bang』という副題がついている。日本語訳も出版されている。『物質は何からできているのか』(ハリー・クリフ著、熊谷玲美訳、柏書房、2023年刊)で、こちらには『アップルパイのレシピから素粒子を考えてみた』という副題がついている。


    ビッグバンの恐ろしい熱の中でどうやって消滅を免れたのか? 私たちは宇宙の誕生の瞬間を理解することができるのだろうか? そして、物質は何からできているのか? そんな疑問にはたして答えられるのか?

    著者のハリー・クリフ(Harry Cliff)は物理学者で、素粒子物理の実験を仕事にしているのだが、この本が扱う範囲は驚くほど広い。宇宙について、そして素粒子について、今わかっていることの全体像を示してくれる。それだけではなく、実証されたのか、されてないのか、されているとしたらどのように実証されたのかも書かれている。

    ハリー・クリフは、実験物理学者というより、素晴らしい作家だ。なぜ物があるのか? すべてはどこから来たのか? 物質が実際に何であるかをどのようにして学んできたのか? ビッグバンから星の爆発を経て、いまの私たちに至るまでの物語は、どれもすべて興味深い。


    『How to Make an Apple Pie from Scratch』の第1章から第7章まで、「Elementary Cooking(初級クッキング)」「The Smallest Slice(最小のスライス)」 「The Ingredients of Atoms(原子の材料)」「Smashed Nuclei(砕かれた核)」「Thermonuclear Ovens(サーモニュークリア・オーブン)」「Starstuff(スタースタッフ)」「The Ultimate Cosmic Cooker(究極の宇宙調理器)」と続くのだが、どこをとっても明瞭で、曖昧さが微塵もない。論理的に、しかも合理的に組み立てられた文章は説得力にあふれている。

    第8章から第14章までの「How to Cook a Proton(プロトンを調理する方法)」「What Is a Particle, Really?(そもそも粒子って何?)」 「The Final Ingredient(最終的な材料)」「The Recipe for Everything(すべてのためのレシピ)」「The Missing Ingredients(足りない材料)」「Invent the Universe(宇宙を発明する)」「The End?(終わり?)」は、がぜん面白くなる。気の合う友たちと語り合うような気分の読書だ。

    最後に(第14章のあとに)ご丁寧にも『How to Make an Apple Pie from Scratch(アップルパイをゼロから手作りする方法)』が書いてある。八人分のアップルパイを138億年かかって作る手順だ。まず宇宙を作る。時空を1溝分の1秒(10-32秒)だけ膨張させ、温度を急激に上昇させ、大量の粒子と反粒子を作り出し、電磁場と強い力の場を生成させたあと、引き続き1兆分の1秒(10-12秒)膨張させて、時空をゆっくり冷やす。そしてヒックス場をオンにする。そのあと物質を作るための複雑な手順がいろいろ細かく書かれているのだが、宇宙が作られてから、表面を水素と酸素と窒素と炭素で覆われた惑星がひとつ出来上がるまでのことが、この本を読んで得た知識でよくわかってしまう。そのわかるという快感が、ここまで読んできた読者への著者からのプレゼントなのだろうと思うと、自然と頭が下がる。運が良ければ、そのあと45億年ほどで、リンゴの木と牛と小麦のような生命体と、それにスーパーマーケットなんかもできているだろうから、あとはアップルパイの材料を買ってきて作るだけ。本はそんなふうに終わる。


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    Everything belongs to earth
    Earth is the Crest of Apple pie
    Everything else, including life are the ingredients of pie
    human life are its topping decoration.

    It certainly takes very long to make an apple pie
    It also seems take long from write to post
    Wondering when will your friend return or never ?

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