Scott Aaronson - Is the Cosmos a Computer?

That the cosmos is a computer sounds like a modern metaphor, a way of explaining how things work. But some make a bolder claim: that the cosmos is in reality a computer, not just as metaphor. This would mean that all that exists in the physical universe is in essence the computational process of the universe itself generating itself. Does that make sense?



Scott Joel Aaronson is a theoretical computer scientist and faculty member in the Electrical Engineering and Computer Science department at MIT. His primary area of research is quantum computing and computational complexity theory more generally.


Closer to Truth, hosted by Robert Lawrence Kuhn and directed by Peter Getzels, presents the world’s greatest thinkers exploring humanity’s deepest questions. Discover fundamental issues of existence. Engage new and diverse ways of thinking. Appreciate intense debates. Share your own opinions. Seek your own answers.

[jean-pierredevent]

- I have here a bean, can you "compute" how the plant will look grown from it???
- Yes, of course, here is some ground, put it in and we'll wait.
That doesn't seem fair.

[bobcabot]

...it means: a computer is a mirror-image of our brain, but our brain is a mirror-image of the universe...

[snarkyboojum]

In this video, Scott Aaronson discusses the concept of whether the universe can be considered a computer. He begins by stating that the concept of computation is broad and can be applied to any law-governed process. He suggests that a more fruitful question is to consider what kind of computation the universe could be. Aaronson's field of expertise is computational complexity theory, which studies the capabilities and limitations of computers and the resources needed for computations. He explains that computational complexity theory focuses on the scaling of resources as a problem increases in size. If the resources required increase exponentially, the problem is considered infeasible. He gives examples of problems that require astronomical amounts of time to solve, such as generalized chess on a large board or the traveling salesman problem. The distinction between checking a result and finding a result is highlighted, leading to the central unsolved problem of theoretical computer science, the P versus NP question. P represents problems that are feasibly solvable by a digital computer, while NP represents problems for which a solution can be recognized efficiently if given. The question asks whether every problem that can be recognized efficiently also has an efficient way to find a solution. Aaronson explains that this question is fundamental to understanding the nature of computation and its relationship to physics. He introduces the concept of quantum computing, which uses quantum mechanical components and can solve problems like factoring large numbers. This discovery suggests that quantum mechanics expands the limits of what is computable in the physical universe. However, other problems like the traveling salesman problem are believed to be unsolvable given the resources of the physical world. Aaronson concludes by stating that while the question of whether the universe is a computer is still unclear, we do know a lot about the kind of problems the universe can solve if it is considered a computer.

Key themes:
1. The nature of computation and its relationship to physics: Aaronson explores the concept of computation and its broad application to any law-governed process. He discusses the central unsolved problem of theoretical computer science, the P versus NP question, which is fundamental to understanding the nature of computation and its relationship to physics.
2. The capabilities and limitations of computers: Aaronson explains computational complexity theory and how it focuses on the scaling of resources as a problem increases in size. He gives examples of problems that require astronomical amounts of time to solve and discusses the distinction between checking a result and finding a result.
3. Quantum computing and the expansion of computability: Aaronson introduces the concept of quantum computing and how it uses quantum mechanical components to solve problems like factoring large numbers. He suggests that quantum mechanics expands the limits of what is computable in the physical universe.

Suggested follow-up questions:
1. How does the P versus NP question relate to the concept of computation in the universe? Are there any potential implications for our understanding of physics?
2. Can you provide more examples of problems that are believed to be unsolvable given the resources of the physical world? How do these limitations impact our understanding of computation and the universe as a computer?

[fparent]

My question is if the universe is a computer, why does it have to solve anything? The game of life is an algorithm that just runs with no real purpose other than to be observed. Assuming the universe is a computer, maybe it was setup with a number of parameters, laws and such and let loose simply for the sake of observing what would come out of it.

[Patrick]

Interesting how cosmic explanations / hypothesis consistently mirror technology of the time.

[jwulf]

Robert Lawrence Kuhn interviews Robert Lawrence Kuhn from the 90's

[carlr]

check out the reflection in the guest's glasses, it looks like the matrix code kinda lol

[skipsch]

With increasingly sophisticated systems & the more power and things they can encompass and do, the more accurately it'll represent the entire universe's system. Back in the day clocks were the fanciest thing, so we compared everything to a clock. Of course since we're smart creatures we're going to see correlations between more sophisticated systems and the entire universe's system. The universe's system will already have all the features you discover in your sophisticated system; your system's constituents didn't come from nowhere, so don't be too surprised.
Also since we're smart we have to imagine much more sophisticated systems than ones we currently have, more than human brains or any computer or clock or other increasingly complex robust system.
Priority should be put on finding more commonalities amongst more or all types of systems, not just brains or computers. There's also communication in plants and fungus and how cities and hierarchies develop, and populations of "excellence" versus "incompetence", all have real common trends/features. I'm not sure what use it would be to say the universe is like an ecosystem or society though.
Maybe something involving curves will be discovered and become a principle or law. Maybe the way info in the brain and the way matter in the universe orients itself is similar to Feynman's "volcano hole" curve in his explanation of the behaviour of atoms when they get too close. That last sentence was just thinking out loud, have a nice week

[joshkeeling]

Back when clocks were the newest and most advanced technology, the universe "ran like clockwork."

[wolfeyes]

It seems as if mathematics is so used to using numbers to describe things that all they see is numbers and maths.
Although i think maths is a good tool to help us understand the universe, i don't think it describes it exactly as it is.

Ask a poet to describe the universe and they will do so in such a way that it's from their point of view, their experiences, and the things they enjoy.
The same could be said for a musician, take holts planets as an example with that.

An artist would paint a universe with colours, shapes, and forms.

Everyone has an idea of how things are based on the way they see things, be it in music, writing, maths, art, or their interests and points of view.
Neither is really wrong just the language us different for each person.

We can understand the things it's made of, the motion and it's dynamics but it no way does it reflect what reality might be.

[DavidRexGlenn]

The universe is not a computer. It is a paint shaker at a Ace Hardware in a town very much like Attumwa, Iowa

[peterpanino]

Can it be programmed? Is there an API for its operating system? Is its logic binary?

[xoulis]

Well... If it is a Computer, it's a Very Slow One!

[matterasmachine]

Universe is not computer, it’s discrete 3D matrix and all matter in it executes algorithm. Each photon consists of around 10^15 discrete pieces. That is the reason fo discreetness of action, heisenberg’s uncertainty principle, relativity, etc.

[jamesruscheinski]

Question of universe being a computer has to do with input and output of a computer; if there is some kind of formulated input into universe that directs the output of physical reality?

[supamatta]

Whoa he s just staring at him glitch and stuck wondering about the battery computer threshold displaying us. Whats the time relative differential of black holes visualing affecting each other.

[Epiousios]

"We can't actually show that there are problems where you can recognize a solution and yet not find one yourself." 7:42

This says a lot about our current state of knowledge in general by my estimation.

[gracerodgers]

Strange, I always imagined it as a timepiece.

[readyfireaim]

This isn't a "simulation", though, this is "contingent".

[david_porthouse]

We can do computer simulations of the Von Karman vortex street, and by analogy there could be an alien computer simulating us. How do they tackle quantum mechanics? We are allowed to ask.