Einstein Was Wrong
Entanglement, The Universe’s Most Impossible Connection
Missed the last one? Last time we figured out how something can actually be in two places at once. Yes, really. → Read it here
Earlier this week I attended an alumni event for my undergrad’s engineering school, UCSB — go Gauchos! Yep, gauchos are the mascot, because Santa Barbara and Argentinian cowboys are like two peas in a pod… obviously.
Anyway, I was chatting with the dean before his talk and made my same old joke, half-truth, half-wishful thinking, that I’ve said a hundred times before. I majored in mechanical engineering, but if I were smart I would have done computer science. Usually it’s met with a laugh because Google engineers eat Boeing engineers’ salaries for lunch. This time, though, the dean abruptly said: no. Mechanical engineering is the hottest major right now. Whaaaaaaat?
Turns out, AI and robotics have not only turned mechanical engineering from being Screech to the Zack Morris of engineering majors, but UCSB has become a massive center for quantum computing, with Google’s own lab right on campus. My first thought was: I have to tell Ari his dad is actually cool.
I came home buzzing, excited to tell Ari and show him the picture from the latest UCSB engineering magazine: a giant, gloriously confusing quantum computer on the cover. Ari’s first thought, of course, was how do you turn the lights on. After spending a few minutes realizing it was indeed a quantum computer and not the latest issue of Chic Chandeliers Monthly — honestly, tell me this doesn’t look more like a chandelier or something out of the strangest science fiction B-movie you’ve ever seen.
What Einstein Was Wrong About
So the conversation moved from quantum chandeliers to how the heck do these things actually work, and why do they look so weird? Well, quantum computing is built on two experimentally validated quantum physics principles. The first is quantum superposition — you know all about that one, and if you don’t, check out my last post here on one of the weirdest physics principles ever. The second is quantum entanglement, which I would argue is the weirdest physics principle of them all, and I will stand that ground no matter what. Come at me, superposition fans.
Quantum entanglement is so mind-bending that it didn’t just break Ari’s brain and mine, it broke the brain of someone most people would immediately name as the smartest human being who ever lived: Albert Einstein. He was vigorously certain he had to be right, and every single ounce of human common sense, built through thousands of years of compounding knowledge, agreed with him. But reality did not.
Spooky Physics
Quantum entanglement is the proven principle that two particles, smaller than an atom (we’re talking quantum here), become linked after interacting with each other. What that means is that if they touch and are then separated by millions and millions of light-years, observing one instantly tells you something about the other.
Just like, and I promised Ari I would add this, if Ari tells a poop joke at school, his brother Joshy would immediately start laughing even though he’s at a completely different school across town. Hot tip: never underestimate the power of solid poop or fart humor.
And this is exactly where Einstein was wrong while being absolutely certain he was right. Bertie (which I’d like to imagine his wife called him) was convinced there had to be some hidden information passing between them somehow. He called it “spooky action at a distance.” The father of relativity, the man who gave us our entire framework for understanding the universe, called it spooky action. I’d also like to think Bertie’s house on Halloween was themed entirely around quantum entanglement.
So What Does That Actually Mean?
Let’s think about two complete strangers who have never met bumping into each other at an airport. We’ll call them Albert and Niels. No real exchange occurs, no talking, no secret handshake, just a passing moment. They get on their respective flights: Albert to Honolulu, Niels to Thailand. Thousands of miles apart.
Later that day, Albert flips a coin, and at that exact moment, Niels on the other side of the world flips the exact same result.
That’s the simplified version of entanglement. But it actually goes much deeper than a coin flip. If you asked Albert what Niels ordered for dinner that night, he could tell you exactly. And Niels could do the same about Albert’s dinner, and for every single meal after that.
After that brief airport interaction, they were no longer two independent people. They became one system. When you check one, you’re learning something about both.
And this was the hardest part to explain to Ari, which is exactly the hardest part Einstein had as well. I told Ari that if you send these particles to opposite sides of the universe, the moment something happens to one, the other somehow already knows. As if the distance between them doesn’t really exist. The incomprehensible distance of our universe is meaningless here.
If this just broke your brain a little, you’re in the right place. Dan & Ari is free, always will be, and we’re just getting started. One click and you’re in.
“But Daddy...”
When I explained this to Ari, his immediate question was kind of obvious in the best way: “But Daddy, why does this only happen with particles smaller than an atom? Didn’t you tell me the other day that atoms are like small galaxies, so they shouldn’t be any different?” And with the confidence of someone who thinks they know more than they do, I gave him a big, strong, confident “Nope, just like superposition, nobody knows why.” Beaming at my sudden realization that I may be a genius, I started thinking of quantum physicist jobs. Luckily, before calling MIT, I decided to look it up. Turns out the only person who really didn’t know was me.
Because entanglement actually doesn’t only work at the subatomic level. Unlike superposition, which is uniquely quantum, entanglement actually happens everywhere. It’s kind of happening to us right now.
Here’s the difference: we aren’t single particles. We’re made of trillions of particles constantly interacting with trillions of other particles every second. Every interaction weakens the original connection a little more.
Here’s an easier way to think about it. A friend at school tells Ari a number. He walks away, and for the rest of the day it’s pretty easy to remember if he focuses on it. Now imagine 1,000 kids each shout a different number at him during the day. The original number gets buried under all the others.
Now instead of 1,000, imagine a trillion.
That gradual washing out of the original connection is called decoherence. The bond didn’t disappear. It just got drowned out.
Parenting Through a Quantum Lens
This week I was driving Ari to his regular after-school STEM program and we were talking about writing this article. I walked him up as I usually do and he hugged me, said “I love you,” and excitedly walked through the door into a room full of robots, circuits, 3D printers, computers for coding, and tons of other cool things. Watching him walk through that door, something clicked. That’s superposition.
STEM is one of near infinite possibilities, and as of right now, at seven years old, all those possibilities, all those doors, are open for him. All of his possible futures exist until a path is chosen. My job as his father isn’t to pick a door. It’s to make sure none of them close too soon, that his superposition state stays open as long as possible. That state is where true wonder and joy live best. It’s what we lose as adults. The fewer possibilities, the less wonder.
And then there’s entanglement. One day (and it’s closer than I’d like) Ari will move out and go chase his remarkable life. A few weeks ago, while leaving NASA’s Johnson Space Center on our way to dinner, Ari casually said:
“Daddy, I probably won’t be able to live next to you and Mommy because this is far away, and I want to work here when I grow up.”
To him it was just any other comment. He said it smiling and immediately moved on to staring out the window at the boats passing by. To me it was a sledgehammer to the heart.
I moved a lot as a kid and I haven’t lived in the same city as my parents in almost twenty-five years. That wasn’t the plan. I think about it more than I let on. But with my kids I feel it differently. More urgently. His comment hit me so hard because I already know exactly what that distance feels like.
What gives me comfort is thinking about it like entanglement. No matter where he goes, we are forever linked, just like two particles that once interacted. Except the bond isn’t fragile quantum information that can be washed out by decoherence. It’s a bond nurtured over seven years, and the ten more we have left before he goes, of love and support.
That bond transcends any distance between us.
We are forever entangled.
If you made it this far, you might as well make it official. Dan & Ari is free, always will be, and the next one is going to be even better. One click and you’re in.
Ari’s Take
“I think it was amazing to learn about how these particles can read each other’s minds, because they don’t have the same mind.”
— Dan & Ari, still figuring our universe out...
This was such a fun and emotional read!!
Some great quantum analogies!