Daina Bouquin: You are walking home without an umbrella.
Daina Bouquin: The forecast said 60%, and you did the math the way everybody does the math.
Daina Bouquin: Which is to say that you didn't.
Daina Bouquin: You looked at the sky and you decided that it would hold.
Daina Bouquin: So now you are hurrying.
Daina Bouquin: Shoulders up, and the rain is coming down in big, scattered droplets.
Daina Bouquin: You watch it land on the sidewalk.
Daina Bouquin: One drop.
Daina Bouquin: Then a dozen.
Daina Bouquin: Dark coins appearing on the pale concrete in no particular order.
Daina Bouquin: You could not say where the next one will fall.
Daina Bouquin: Nobody could.
Daina Bouquin: Not you.
Daina Bouquin: Not whoever wrote the forecast.
Daina Bouquin: Not anyone who has ever lived.
Daina Bouquin: And that, right there.
Daina Bouquin: The randomness.
Daina Bouquin: That is one of the last wild things.
Daina Bouquin: And it's everywhere.
Daina Bouquin: It is the exact fork of the lightning.
Daina Bouquin: Drawn once across the dark and never again.
Daina Bouquin: It is the freckles on your arm.
Daina Bouquin: It is the hiss between two radio stations.
Daina Bouquin: The world throws off randomness the way it throws off heat.
Daina Bouquin: Constantly.
Daina Bouquin: For free.
Daina Bouquin: You cannot bottle it.
Daina Bouquin: You cannot ask the storm to wait.
Daina Bouquin: It falls and the randomness is gone.
Daina Bouquin: Which would not matter at all if we didn't need it.
Daina Bouquin: But we do need it.
Daina Bouquin: We need it because it is how we try to see the future.
Daina Bouquin: To determine whether the river comes over its banks tonight while you sleep.
Daina Bouquin: Whether the funnel touches down on your street or one in the next town over.
Daina Bouquin: To see the future, we build a little sky inside a machine.
Daina Bouquin: We tell the sky everything we know about the air right now and about physics.
Daina Bouquin: And then we let it run the sky forward, out ahead of the real weather.
Daina Bouquin: But the air will not sit still to be copied.
Daina Bouquin: Miss one gust of wind, one pocket of warmth too faint to measure, and your little digital sky evolves in the completely wrong direction.
Daina Bouquin: So we do not run the simulation once.
Daina Bouquin: We run it 50 times.
Daina Bouquin: And each run starts with a tiny random nudge to stand in for everything we don't know.
Daina Bouquin: Each nudge creates a slightly different tomorrow.
Daina Bouquin: Then we count how many of those tomorrows end in rain.
Daina Bouquin: And here is the thing about the machine dreaming up those tomorrows.
Daina Bouquin: It cannot make a single one of those random nudges on its own.
Daina Bouquin: We had to find the randomness somewhere and pour it in.
Daina Bouquin: And the randomness we pour into nearly every forecast, every simulated flood, every imagined storm.
Daina Bouquin: It is not real.
Daina Bouquin: It's a counterfeit.
Daina Bouquin: We faked it.
Daina Bouquin: I'm Daina Bouquin, and this is Found in the M achine.
Daina Bouquin: To you understand why anyone would fake randomness you have to understand how hard the real thing is to catch.
Daina Bouquin: Go back to 1947.
Daina Bouquin: To a low building in Santa Monica, close enough to the ocean that you could smell it if you opened a window.
Daina Bouquin: Where a new outfit called RAND was doing mathematics for the Air Force.
Daina Bouquin: Someone there needed random numbers.
Daina Bouquin: Not a handful.
Daina Bouquin: A million.
Daina Bouquin: Clean ones.
Daina Bouquin: With no human thumb on the scale.
Daina Bouquin: Because you could never get a million random numbers out of a person.
Daina Bouquin: Ask anyone to rattle off random digits and they will lean on some without realizing it.
Daina Bouquin: They'll make little patterns without meaning to.
Daina Bouquin: They'll say seven too much.
Daina Bouquin: People are pattern machines.
Daina Bouquin: It is one of the things we cannot stop ourselves from being.
Daina Bouquin: And the people at RAND knew that.
Daina Bouquin: So they built a chaos engine instead.
Daina Bouquin: It was, more or less, an electronic roulette wheel.
Daina Bouquin: A wheel with 32 slots spun by raw electrical noise.
Daina Bouquin: The frantic static inside a gas tube, whipping through thousands of revolutions and landing on one number every second.
Daina Bouquin: It clattered.
Daina Bouquin: It clicked.
Daina Bouquin: It punched its chaos into stiff paper cards hour after hour, day after day.
Daina Bouquin: And it worked.
Daina Bouquin: Sort of.
Daina Bouquin: Because it turns out that building a thing with no habits at all is almost impossible.
Daina Bouquin: The tubes degraded.
Daina Bouquin: They were sensitive to the room's temperature.
Daina Bouquin: They felt the grid's voltage flutter when the building's power dipped.
Daina Bouquin: And slowly, quietly, a faint shadow of a pattern would creep back in.
Daina Bouquin: So you would have to shut the machine down and tune it, and then it would behave for a while.
Daina Bouquin: And then it would drift again.
Daina Bouquin: Which meant someone had to check.
Daina Bouquin: Someone had to take a million numbers and hunt through them for ghosts of a pattern.
Daina Bouquin: Her name was Bernice Brown.
Daina Bouquin: Before Rand, she had been in Ames, Iowa, at the statistics program that became the first statistical laboratory in the country.
Daina Bouquin: In 1932, she became the second person ever to earn a master's degree in statistics there.
Daina Bouquin: At RAND, once the machine had spat out its million digits.
Daina Bouquin: Her job was to make sure they were completely meaningless.
Daina Bouquin: So she counted how often each digit appeared.
Daina Bouquin: Whether pairs showed up too often, whether runs ran too long, test after test, by hand and on IBM tabulating machines, feeding in tray after heavy tray of punched cards, day after day, for years.
Daina Bouquin: Tedious, physical, invisible work.
Daina Bouquin: And at the end of it all, after tests and retests and one final mathematical shuffle to scrub out the machine's last stubborn leanings, Bernice Brown signed off.
Daina Bouquin: She wrote that nothing in her tests argued against calling these numbers random.
Daina Bouquin: Not these are random.
Daina Bouquin: No one can ever prove that.
Daina Bouquin: Only I looked as hard as I know how to look and I could not catch them being anything else.
Daina Bouquin: Her certified numbers were eventually printed and bound into a book.
Daina Bouquin: A real book published in 1955 that you could order in the mail.
Daina Bouquin: It is called A Million Random Digits with 100,000 Normal Deviates.
Daina Bouquin: You can still buy a copy today.
Daina Bouquin: And people did buy it.
Daina Bouquin: Scientists, pollsters, lottery designers.
Daina Bouquin: For years, if you needed real randomness, you did not make it.
Daina Bouquin: You looked it up.
Daina Bouquin: The book even came with instructions.
Daina Bouquin: You were not supposed to start on page one.
Daina Bouquin: You were told to open the book somewhere unpredictable and read off in an unpredictable direction.
Daina Bouquin: Even the Book of Chaos needed you to bring a little chaos of your own.
Daina Bouquin: So this is what randomness cost in 1955.
Daina Bouquin: A machine that fought you.
Daina Bouquin: A woman who spent years checking every digit.
Daina Bouquin: A book of certified nonsense that you kept on a shelf.
Daina Bouquin: Now, around that same time, a man was lying in a hospital bed playing cards.
Daina Bouquin: His name was Stanisław Ulam, and he was a Polish-American mathematician.
Daina Bouquin: In 1946, he had nearly died.
Daina Bouquin: A sudden encephalitis, an emergency brain surgery.
Daina Bouquin: And as he recovered, he played solitaire.
Daina Bouquin: And somewhere in there he got curious.
Daina Bouquin: What are the odds that a given hand of solitaire can be won at all?
Daina Bouquin: He tried to work it out properly with pure mathematics.
Daina Bouquin: And the calculations just ballooned beyond reach.
Daina Bouquin: So he gave up on elegance and just played.
Daina Bouquin: Lots of hands.
Daina Bouquin: And he counted how often he won.
Daina Bouquin: He figured, don't solve the problem.
Daina Bouquin: Simulate it.
Daina Bouquin: Run it over and over with the deck shuffled differently each time, and let the count become your answer.
Daina Bouquin: Ulam brought that idea back to his colleagues and one of them saw immediately what it could do. His name was John von Neumann, a mathematician of terrifying range who played German marching music too loud in his office, and who was, at that moment, trying to understand what happens inside an exploding bomb.
Daina Bouquin: You could write that problem down in theory.
Daina Bouquin: Every neutron, every trajectory through a chunk of metal the size of a grapefruit.
Daina Bouquin: But solving it would take longer than the universe has been alive.
Daina Bouquin: Or you could do what Ulam had done with the cards.
Daina Bouquin: Follow one imaginary neutron.
Daina Bouquin: When it strikes a nucleus, roll the dice.
Daina Bouquin: Does it bounce?
Daina Bouquin: Is it absorbed?
Daina Bouquin: Does it split the atom?
Daina Bouquin: That random roll of the dice would determine the outcome.
Daina Bouquin: And von Neumann needed millions of rolls.
Daina Bouquin: More than any book could hold.
Daina Bouquin: So he came up with a trick.
Daina Bouquin: Take a number, square it, then reach into the middle of the answer and pull out a few digits.
Daina Bouquin: That's your next number.
Daina Bouquin: Now do it again and again.
Daina Bouquin: Plain, fast, repeatable arithmetic.
Daina Bouquin: And if you squint, the numbers it throws off look random.
Daina Bouquin: They jump around and feel unpredictable.
Daina Bouquin: They are not.
Daina Bouquin: Of course they are not.
Daina Bouquin: Feed the trick the same starting number, the same seed.
Daina Bouquin: And it hands you the exact same sequence.
Daina Bouquin: There is no more chance in it than in a times table.
Daina Bouquin: And nobody knew that better than von Neumann.
Daina Bouquin: He said it himself.
Daina Bouquin: Anyone who uses arithmetic to produce random digits is, of course, in a state of sin.
Daina Bouquin: For decades, the fakes were good enough.
Daina Bouquin: Because for most of what we ask randomness to do, a good fake is fine.
Daina Bouquin: For weather, for bombs, for the slow patient work of science, von Neumann's sin was pretty much good enough.
Daina Bouquin: But then we started asking randomness to do something new.
Daina Bouquin: Not to imagine the future, but to keep our secrets.
Daina Bouquin: You see, when you send a message you do not want read, or when money moves, the locks that protect all of it are built from random numbers.
Daina Bouquin: And a secret built on a fake is just a secret waiting for the right person to notice.
Daina Bouquin: Like in 1995, two graduate students at Berkeley noticed.
Daina Bouquin: They pulled apart the web browser Netscape, which was at the time the front door to the internet, and found that the quote, random numbers securing its traffic, were seeded with things like the time of day.
Daina Bouquin: Not chaos, just a clock.
Daina Bouquin: And so in minutes the locks came open.
Daina Bouquin: And so, after half a century of getting away with it, we discovered that we still needed the real thing.
Daina Bouquin: Genuine unpredictability, caught from the physical world.
Daina Bouquin: Bernice Brown's kind.
Daina Bouquin: Computer science has a word for it.
Daina Bouquin: They call it entropy.
Daina Bouquin: And we were sent back out to hunt for it.
Daina Bouquin: Here is what we worked out.
Daina Bouquin: To keep our secrets, we do not need a million real random numbers.
Daina Bouquin: We only need the starting points, the seeds.
Daina Bouquin: Once you have a truly unpredictable seed, the fast, cheap arithmetic can take it from there.
Daina Bouquin: So the hunt became a hunt for seeds.
Daina Bouquin: And once you go looking the mess is everywhere, the thermal noise inside a resistor, the decay of a radioactive atom, the jitter of the exact microsecond you happen to move your mouse.
Daina Bouquin: Your computer is scavenging entropy off of you right now, gathering up your tiny accidents and pooling them like rainwater.
Daina Bouquin: And in one building in San Francisco, a company called Cloudflare keeps a whole wall of lava lamps.
Daina Bouquin: Blobs rising and folding and splitting and never taking the exact same shape twice.
Daina Bouquin: A camera watches the wall, and a computer turns every pixel, its position, brightness, and color, into numbers.
Daina Bouquin: The exact posture of every slow molten blob becomes a seed, feeding the cryptographic keys that secure web traffic for millions of sites.
Daina Bouquin: If you walked in front of that wall, your shadow would shape the randomness too.
Daina Bouquin: Some tiny fraction of the internet's locks would be forged in part from the outline of you.
Daina Bouquin: We built machines that can do almost anything.
Daina Bouquin: They can play out fifty tomorrows no problem.
Daina Bouquin: They can follow a neutron through a bomb.
Daina Bouquin: And lately they can talk.
Daina Bouquin: You may have had a conversation with one recently.
Daina Bouquin: Every time one of those machines chooses its next word, it rolls dice.
Daina Bouquin: And they are von Neumann's dice.
Daina Bouquin: Fed at the very start by a seed of real entropy scavenged from the physical world.
Daina Bouquin: Because that is the one thing no machine can do.
Daina Bouquin: The most powerful things we have ever built come to the physical world like beggars.
Daina Bouquin: To the static.
Daina Bouquin: To the lava.
Daina Bouquin: The machines cannot make it.
Daina Bouquin: Bernice Brown could spend years checking and never prove it.
Daina Bouquin: Von Neumann could only fake it, and the sky is giving it away for free.
Daina Bouquin: You feel it on the back of your neck as you hurry home.
Daina Bouquin: I'm Daina Bouquin, and this is Found in the Machine.
Daina Bouquin: If you enjoy these stories, please rate and review this podcast wherever you listen.