Sean Carroll

And that's what we're sort of

So, okay, now we'll raise our level of technicalities a little bit to try to address this question.

Why does this super austere, bare-bones quantum mechanical theory, which I have called Mad Dog Everettianism, Mad Dog Everettianism was a phrase that we, Ashmeet Singh and I, a former student and current professor,

collaborator, coined after what Owen Flanagan, who's a philosopher, dubbed Alex Rosenberg.

Remember, Alex Rosenberg was a previous guest on Mindscape, and Owen referred to Alex as a mad dog naturalist, to the extent that you can be a mad dog naturalist.

Like, you're not only a naturalist, you're taking naturalism as far as it can possibly go, the most extreme version, right?

The X Games version of naturalism.

And now we're doing that for

Everettianism.

We're saying, like, what is the least we can get away with?

What is the most fundamental stuff?

So if you asked people on the street, physicists on the street, make sure your street is outside a physics department, ask them, OK, what defines a quantum mechanical theory?

I don't mean what defines quantum mechanics, like that's a, you know, Everett versus pilot waves or Copenhagen or whatever.

I mean, within some particular version of quantum mechanics, what chooses a model?

What lets you know that this is the simple harmonic oscillator, that's the electromagnetic field, right?

This is the electron in the hydrogen atom or whatever.

There's different models for different quantum theories.

So what do you have to tell me to specify that theory?

And people might say things like, well, okay, you have a Hilbert space.

That's the space of all the possible quantum states.