Sarah Walker

I think so. I mean, I don't think, there's always going to be the paradox of another meta level you could build on the meta level, right? So like if you assume this is your universe and you're the observer outside of it, you have some meta description of that universe, but then you need a meta description of you describing that universe, right? So, you know, this is one of,

The biggest challenges that we face being observers inside our universe and also, you know, why the paradoxes and the foundations of mathematics and any place that we try to have observers in the system or a system describing itself show up. But I think it is possible to build a physics system.

The biggest challenges that we face being observers inside our universe and also, you know, why the paradoxes and the foundations of mathematics and any place that we try to have observers in the system or a system describing itself show up. But I think it is possible to build a physics system.

The biggest challenges that we face being observers inside our universe and also, you know, why the paradoxes and the foundations of mathematics and any place that we try to have observers in the system or a system describing itself show up. But I think it is possible to build a physics system.

that builds in those things intrinsically without having them be paradoxical or have holes in the descriptions. And so one place I think about this quite a lot, which I think can give you sort of a more concrete example, is the nature of what we call fundamental. So we typically define fundamental right now in terms of the smallest indivisible units of matter.

that builds in those things intrinsically without having them be paradoxical or have holes in the descriptions. And so one place I think about this quite a lot, which I think can give you sort of a more concrete example, is the nature of what we call fundamental. So we typically define fundamental right now in terms of the smallest indivisible units of matter.

that builds in those things intrinsically without having them be paradoxical or have holes in the descriptions. And so one place I think about this quite a lot, which I think can give you sort of a more concrete example, is the nature of what we call fundamental. So we typically define fundamental right now in terms of the smallest indivisible units of matter.

So again, you have to have a definition of what you think material is and matter is. But right now, what's fundamental are elementary particles. And we think they're fundamental because we can't break them apart further.

So again, you have to have a definition of what you think material is and matter is. But right now, what's fundamental are elementary particles. And we think they're fundamental because we can't break them apart further.

So again, you have to have a definition of what you think material is and matter is. But right now, what's fundamental are elementary particles. And we think they're fundamental because we can't break them apart further.

And obviously we have theories like string theory that if they're right, would replace the current description of what's the most fundamental thing in our universe by replacing it with something smaller. But we can't get to those theories because we're technologically limited.

And obviously we have theories like string theory that if they're right, would replace the current description of what's the most fundamental thing in our universe by replacing it with something smaller. But we can't get to those theories because we're technologically limited.

And obviously we have theories like string theory that if they're right, would replace the current description of what's the most fundamental thing in our universe by replacing it with something smaller. But we can't get to those theories because we're technologically limited.

And so if you look at this from a historical perspective and you think about explanations changing as physical systems like us learn more about the reality in which they live, we once considered atoms to be the most fundamental thing. And, you know, it literally comes from the word indivisible.

And so if you look at this from a historical perspective and you think about explanations changing as physical systems like us learn more about the reality in which they live, we once considered atoms to be the most fundamental thing. And, you know, it literally comes from the word indivisible.

And so if you look at this from a historical perspective and you think about explanations changing as physical systems like us learn more about the reality in which they live, we once considered atoms to be the most fundamental thing. And, you know, it literally comes from the word indivisible.

And then we realized atoms had substructure because we built better technology, which allowed us to quote unquote, see the world better and resolve smaller features of it. And then we built even better technology, which allowed us to see even smaller structure and get down to the standard model. particles.

And then we realized atoms had substructure because we built better technology, which allowed us to quote unquote, see the world better and resolve smaller features of it. And then we built even better technology, which allowed us to see even smaller structure and get down to the standard model. particles.

And then we realized atoms had substructure because we built better technology, which allowed us to quote unquote, see the world better and resolve smaller features of it. And then we built even better technology, which allowed us to see even smaller structure and get down to the standard model. particles.

And we think that there might be structure below that, but we can't get there yet with our technology. So what's fundamental, the way we talk about it in current physics is not actually fundamental. It's the boundaries of what we can observe in our universe, what we can see with our technology. And so if you want to build a theory that's about us and about what