I recently attended a singer-songwriter’s performance with my buddy Max. I have difficulty sitting still, so I’d brought paper and some markers to draw horrible cartoons while we listened.
After the show, Max and I caught up. We briefly mentioned our work (he is building things; I am alternating between typing, reading children’s books, and spraying down my popsicle-sticky kids with a hose) and started hashing philosophy. Max digs the old stuff – he’s currently reading Lucretius’s On the Nature of Things, which speculates on both the existence of atoms and reasons why we are conscious.
I told him once that K won’t let me talk about free will at parties, so Max often goads me into it. He’s always loved the image of K hovering with a flyswatter, waiting for me to broach her ire by describing the experiment that would disprove the existence of free will. “We can’t do it yet, but if a non-destructive brain scan at sufficient molecular accuracy … “ SWAT!
I described Hugh Everett’s many-worlds interpretation of quantum wave-function collapse – the idea that with every coin-flip, the universe splits into two and time keeps marching on with the coin having landed both heads and tails. A lot of physicists like dispensing with probability and randomness. Not me – I think the world needs a little chaos. Even if our choices were totally unpredictable, we might not have free will, but if the universe was predictable, sensible and orderly, then we definitely wouldn’t be free.
If you feel like you have free will, that’s almost the same as having it – but how free would you feel if researchers could strap you into a scanner and predict your fate more impeccably than any fortuneteller?
And then, because Max and I always bring up Albert Camus’s The Myth of Sisyphus when we discuss the meaning of life, we had to talk about the experiment that would let you prove Everett’s theory (but only to yourself). I’ve written about this previously, in an essay on my father-in-law and the science of resurrection, but the shorthand description of the experiment is “quantum-mechanical suicide.”
If every coin flip created a new world, and inside one your consciousness would be extinguished before you learned the result of the flip, then you could only consciously perceive yourself as experiencing the other outcome. Someone could flip a coin hundreds of times and you’d always see it landing heads, if the you inside every tails world was instantly ablated.
I was scribbling out diagrams, jotting numbers, and drawing an experimental apparatus with a research subject exploding into flames. Max leaned back, folded his arms over his chest, and mused, “But what I want to know is where love comes into it.”
I added a few more jagged flames, then set down my pen.
Look, I’m a clever dude. I’ve always been good at math, despite having taken very few math classes. I’m well read, hard working, and adept at solving puzzles. But I was never the best with emotions. Before I had kids, nobody would’ve mistaken me for any sort of love expert.
I stuttered a little, then described quantum entanglement (also referred to as “spooky action at a distance” – Jim Holt wrote a lovely essay for the New York Review of Books about it). Particles that are linked stay linked.
Max shook his head. We both knew that wasn’t really love.
But I’m a cold, rational scientist. Max trusts his intuition that something mystical is happening in the world. What kind of explanation might satisfy us both?
So we tried again. The world is real. There is, as best we can tell, a single, objective reality surrounding us. But our consciousness has no access to that world.
In reality, the computer I’m typing this essay on is composed of mostly empty space. Electrons flit blurrily around atomic nuclei – when I reach toward the keys, electrons in my fingertips are repelled, giving me the illusion that the computer is solid. One by one receptors in the cone cells of my eyes interact with incident photons, letting me believe that I am constantly seeing a room full of smooth, hard surfaces. My consciousness gobbles sensory data and creates a representation of the world.
And it’s within those representations that we live. Some philosophers question why humans are conscious. Others speculate that iPhones have consciousness as well. Just like us, a modern telephone integrates a wide variety of external perceptions into its conception of the world.
In any case, because we live within our perception of the world, as opposed to the world per se, love really does change the universe. By opening ourselves up to the world, we suddenly find ourselves to be inside a different world. A physicist might not notice the difference after you let yourself love – but that physicist isn’t inside your head. A physicist’s truth is not always the truth that matters.
Which I am very grateful to Max for teaching me.
Header image from The Scientific Cartoonist.