“Have I come back to tragedy and death again?”

We left off yesterday with Erwin Schrödinger and his magical cat, trapped in a thought experiment about quantum indeterminacy that threatens to destroy us all.

Here’s how it works: The theoretical cat is placed in a sealed chamber with a Geiger counter, a hammer, a flask of cyanide, and a small chunk of something radioactive, which may or may not decay over the course of an hour. Within that hour, there are two possibilities:

#1. The atom decays, which is detected by the Geiger counter, which trips a sensor that makes the hammer smash into the flask, releasing the cyanide and killing the cat.

#2. The atom doesn’t decay, which means no Geiger, no hammer, no cyanide. In that case, the cat is alive at the end of the hour, and it can go about its business.

Now, according to quantum mechanics, the atomic decay in the radioactive substance is in both states simultaneously — both decayed and not — until it’s observed, at which point it resolves into one state or the other. And if the cat’s life is determined by the unresolved atomic decay, then the cat is both alive and dead at the same time — until you open the box and look inside, which causes the wave function to collapse into either “alive cat” or “dead cat”. And then you feed the cat, or bury it, as appropriate.

But Schrödinger completely missed the third alternative, which is that the cat would look at all this equipment, and figure out what’s going on.

At that point, you have an undead cat, sitting alone in a steel box with a flask of cyanide, a hammer and an active source of plutonium, and nothing to do for the next fifty-five minutes but think about the future. Schrödinger has created a dangerous supernatural entity, and provided it with an arsenal.

You don’t resolve a situation like this by opening the box. Opening the box is the beginning of act two.

Continue reading Episode 870: The Collapsing Cat →