Chapter 2 introduction

The physicist Leo Szilard once said to his friend Hans Bethe that he was about to write a diary: "I'm not going to publish it. I just want to record the facts for God's reference." "Don't God know those facts?" Bate asked. "Yes," said Szilard, "he knew the facts, but he did not know the facts described in this way." --Hans Christian von Bayer, The Conquest of the Atom welcome.congratulations.I'm glad you actually succeeded.I know that it is not easy to come into this world.In fact, I think it's a little harder than you know. First, you are here now, and trillions of loose atoms had to come together somehow to create you in complex and strange ways.This arrangement is very special, very special, never before, only once in existence.For many years to come, these little particles will (I hope) work billions of times without compromising ingenious cooperation to keep you intact for one of the most satisfying and pleasing journeys, which is survival.

Why atoms ask for trouble like this is not quite clear.Forming you is not a pleasant affair for atoms.For all their preoccupation, the atoms that make up you don't really care about you—in fact, they don't even know where you are.They don't actually know where they are.They are, after all, mindless particles, lifeless themselves. (If you took a pair of tweezers and pulled the atoms out of you one by one, you would be a mass of fine atomic dust, none of which had ever been alive, and which had all been you It's an interesting thought.) Yet, during your existence, they all serve the same purpose: to make you you.

Atoms are fragile, and the moment of their dedication is fleeting -- literally fleeting, which is bad news.Even very long-lived humans only live a total of about 1 million hours.And when that not-too-distant end, or some other end along the way, flies in front of you, for unknown reasons, your atoms will announce the end of your life, break up, and quietly go away to be something else .That's it for you. Still, it happened, and you can be glad.In general, as far as we know, these kinds of things don't exist anywhere else in the universe.It is indeed strange that atoms have come together so generously and harmoniously to form life on earth that the same atoms would not do so elsewhere.Not to mention anything else, from a chemical point of view, life is only found in this world, which is incredible: carbon, hydrogen, oxygen, nitrogen, a little calcium, a little sulfur, plus a little other very common elements -- Stuff you can find in any general pharmacy -- these are all you need.The only thing special about atoms is this: they form you.Of course, this is the miracle of life.

Whether or not atoms form life elsewhere in the universe, they form many other things; indeed, they form anything but life.Without atoms, there would be no water, no air, no rocks, no stars and planets, no distant clouds, no swirling nebulae, nothing else that makes the universe so fascinating and concrete.Atoms are so plentiful, so essential, that it's easy to overlook how necessary they actually are. There is no law that requires the universe to be filled with particles of matter that produce the light, gravity, and other physical properties that we depend on for our existence.There is actually no need for a universe at all.For a long time there was no universe.There were no atoms then, no universe for atoms to float around in.Nothing -- nothing anywhere.

So, thank goodness for atoms.With atoms, though, they come together willingly, and that's only part of what it takes to get you into this world.You're in this place now, living in the 21st century, and you're smart enough to know it's happening, and you also have to be the beneficiary of an extraordinary string of biological good fortune.It's a very delicate thing to survive on Earth.Of the hundreds of billions of species that have existed since the beginning of time, most -- it is thought to be 99.9 percent -- no longer exist.You see, life on Earth is not only short, but frustratingly fragile.It is an interesting feature of our existence that we arose from a planet that was good at creating life, but even better at destroying it.

The average species on Earth lasts only about 4 million years, so to be here for billions of years, you'd have to keep changing like the atoms that made you.Prepare yourself for everything to change—shape, size, color, species attributes, etc.—to change repeatedly.This is easier said than done because the process of change is fluid.Going from "primitive atomic particles of the cytoplasm" (in the words of Gilbert and Sullivan) to sentient, erect modern humans requires you to continually generate new traits over an exceptionally long period of time and in exceptionally precise ways .So at various times in the past 3.8 billion years you hated oxygen, then loved it, grew fins and limbs and beautiful wings, laid eggs, licked the air with a fork-like tongue, once looked oily , furry, lived underground, lived in trees, once as big as a moose, as small as a mouse, and over a million other things.These are all evolutionary steps necessary, and by the slightest deviation, you might now be licking algae from cave walls, or lounging like walruses on some pebble beach, or Exhale the air through the nostrils on the top of your head, then descend to a depth of 18 meters for a mouthful of delicious earthworms.

Not only have you been very lucky since time immemorial, belonging to a favored evolutionary process, but you have also been extremely - one could say miraculously - lucky in terms of your own ancestry.Come to think of it, over the course of 3.8 billion years, a period longer than mountains, rivers, and oceans on Earth, which ancestors of both your parents were attractive, found a mate, and were healthy Those who are able to have children are lucky enough to live to the age of having children.None of your ancestors were crushed, eaten, drowned, starved, stuck, injured early in life, or unable to put a small Bubble genetic material is released to the right partner, so that the only possible genetic combination process continues, and finally in an amazingly short time-produced you.

This book is about how this happens—especially how we go from not being at all to being something, and then how a little bit of that being becomes us.I will also say something about the period and before that.This of course involves a lot of things, so this book is called, although it is not and cannot be. But, with luck, you may feel that way to some extent by the time you finish this book. My original inspiration for writing this book, for what it's worth, came from a popular science book I had when I was in fourth or fifth grade.It was a textbook from a school in the 1950s - at first glance it looked crumpled, obnoxious, and heavy - but there was an illustration on the first few pages of the book that immediately smitten me : A cutaway view showing the interior of the Earth, as if you took a large knife, cut into the planet, and carefully removed a wedge representing about a quarter of the behemoth.

It's hard to believe how I've never seen this type of illustration before, I remember being completely mesmerized.I do think, at first, that my interest was based on a personal imagining of the unsuspecting stream of traffic going east across the states of the American plains, suddenly over the edge, and crashing into a 6,000-plus-kilometer gap between Central America and the North Pole. gradually turned my attention to the scientific implications of the illustration, and realized that the Earth was composed of well-defined layers, with a heating sphere of iron and nickel at the center.

According to the above description, this sphere is as hot as the surface of the sun.I remember thinking in infinite amazement, "How did they know?" I firmly believe in this information—I still tend to believe scientists as much as I trust doctors, plumbers, and other holders of mysterious information—but I can't imagine how the human brain can be sure in the world. What does the place thousands of kilometers below us look like, and what is it made of, and that is invisible to the naked eye and impenetrable to X-rays.To me, that was nothing short of a miracle.This has been my approach to science ever since.

I was so excited that night that I took the book home and opened it before dinner—I think it was because of this gesture that my mother touched my forehead to see if I was sick --Turned to the first page and read. It turned out that the book wasn't exciting.Actually, it's not all-encompassing.First, it doesn't answer any of the questions the illustrations raise in the curious minds of normal people: how could there be a sun in the center of our planet, and how would they know its temperature?If it's burning down there, why isn't the ground under our feet hot to the touch?Why isn't the rest of the interior melting, or is it melting?If the core of the earth finally burns out, will some part of the earth collapse into that space, leaving a large hole in the ground?And how do you know this?How did you figure it out? But, oddly enough, the author doesn't say a word about these specific questions--in fact, he doesn't say a word about any questions, except about anticlines, synclines, axis deviations, and so on.He seems to make everything unfathomable on purpose in order to keep the good stuff a secret.As the years went by, I began to think that it wasn't entirely a personal motive.There seems to be a general conspiracy among textbook authors to make sure that the material they write never gets too close to the slightly interesting, or at least keeps away from the obviously interesting. Now, I know that there are many, many popular science writers who write accessible and exciting prose - I can point to Timothy Ferriss, Richard Forte and Tim Furlan at a glance Nary and three (not to mention the late and brilliant Richard Feynman) -- but, sadly, none of them wrote the textbooks I used.The textbooks I've used have all been written by men (always men) with an interesting idea, and American kids would love chapters ending with question sections for them to ruminate on in their own time.So I was brought up convinced that science was terribly boring, but at the same time I thought it didn't have to be: science could be very interesting, if only I could.For a long time, this became my position. Then, much later--I think about four or five years ago--I was on a long trip over the Pacific Ocean, and looking out the window of the plane, I saw a bright moon in the sky, and a sprinkling of stars below it. The endless ocean full of silver moonlight, suddenly, a strong sense of uneasiness surged into my heart. I, who have traveled all over the world, feel that I have been in it for a long time, and I can only live in it in this life. lack of understanding.For example, I don't know why sea water is salty, but the water in the Great Lakes is fresh.I have no idea.I don't know if the water is going to get saltier or less salty over time, or if the saltiness of the water is a concern for me. (I'd love to tell you that until the 1970s, scientists didn't know the answers to these questions. They just whispered about them.) Of course, the salinity of seawater is only a tiny fraction of the things I don't know.I don't know what a proton is, what a protein is, don't know about quarks in quasars, don't understand how geologists can tell the age of a layer of rock on a canyon wall just by looking at it - I really don't know anything .Gradually, I was eager to know a little about these issues, especially how they calculated them.How scientists solve these problems -- this is always the greatest wonder to me.How do they know the weight of the earth, how old are the rocks, what is actually deep in the heart of the earth?How do they know how and when the universe began and what it was like when it began?How do they know what's going on inside the atom?How come scientists often seem to know almost everything, yet still can't predict earthquakes, or even tell us exactly whether we should bring an umbrella to the game next Wednesday?What the hell was going on--especially in retrospect? So I decided to spend part of my life—it turned out to be three years—to read books and newspapers, and to seek out patient, respected experts who were willing to answer many special questions that no one had asked.I'd like to see if it's possible to understand and apprehend -- even admire and appreciate -- the wonders and achievements of science on a level that doesn't require much specialization or knowledge, and that isn't entirely superficial . This was my idea, my hope, and this book is written with that intention in mind.Anyway, we've got a lot to cover, and it's far from a million hours to do it, so here we go.