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Why is there forever the assumption that the universe is governed by a simple set of rules? What if the universe is actually an enormous java program with a 10,

Why is there forever the assumption that the universe is governed by a simple set of rules? What if the universe is actually an enormous java program with a 10,000 line Utils.java file? Also this part definitely conjures up a certain series of sci-fi novels popular on HN (and elsewhere): "So one of the unexpected implications of our models is that there can be dimension fluctuations in our universe. And in fact it seems likely that our universe started essentially infinite-dimensional, only gradually “cooling” to become basically three-dimensional. And though we haven’t yet worked it out, we expect there’ll be a “dimension-changing cosmology” that may well have definite predictions for the observed large-scale structure of our universe." Dimensional warfare, baby! Anyway Wolfram gets a lot of hate but honestly I'm glad that some smart dude is using his financially-independent time to go on wild theoretical excursions into what interests him. Living the dream.

quux 6y ago
Sounds like he read "Death's End" by Liu Cixin and got inspired.
- _Microft 6y ago
  Is that the book where aliens forget to fold some dimensions while engineering something and it then rains superstrings onto a planet or something like that?
  - ebruchez 6y ago
    They do some folding, but I don't remember the "raining superstrings" part. In any case, it's an incredible trilogy. I loved it and I recommend it.
    - Karsteski 6y ago
      I second this. A Remembrance of Earth's Past is one of the best SciFi series I have ever read. I even reread it a year later, and now a few months after that I wish I had time to reread it again. I got my girlfriend, mother and many friends to read the series as well :)
jhrmnn 6y ago
One argument is that the approximate models of nature we know of (general relativity, electrodynamics) are very simple. So it seems that the underlying unifying theory shouldn’t be some huge complex monstrosity. But maybe it is
hackinthebochs 6y ago
>Why is there forever the assumption that the universe is governed by a simple set of rules? What if the universe is actually an enormous java program with a 10,000 line Utils.java file? For a given set of observations, the simplest set of posits that explain those observations are more likely to be true as there are fewer ways to "bake in" the observations into the model.
analog31 6y ago
I would approach it from the opposite direction. Physics starts with that assumption, not because it is believed to be fundamentally true, but because we're curious about how far that assumption can take us. And while not the same as simplicity per se, there are additional assumptions, such as that the rules are uniform over space and time, and that they concern phenomena that are amenable to naturalistic inquiry. The surprise, and perhaps why it continues to be a pursuit, is just how far it's taken us. My reading of history suggests that in the 17th century, scholars assumed that the inquiry would either run into a dead end, or merge with theology. Neither has happened yet. It certainly doesn't prohibit humanity from dropping any of those rules and exploring the universe in alternate ways, so it's not a great loss if physics sets some boundaries for itself.
patcon 6y ago
> Anyway Wolfram gets a lot of hate but honestly I'm glad that some smart dude is using his financially-independent time to go on wild theoretical excursions I agree! I truly appreciate this man. And he seems kind and well-intentioned when I've watched his videos. The silly mental imagery that I have of him, which I don't intend in a mean-spirited way: that his ego is such that he goes well beyond naval-gazing, beyond even sniffing his own rear, and then leans so far that he's looking up at the stars and the universe from a very different perspective than most everyone else ;)
coliveira 6y ago
In fact it is more probable that the universe started from a very simple set of rules than a very complex java file. There are a lot of assumptions behind a java file, I mean, a huge lot of assumptions. A simple universe is not only more beautiful, but it is also more probable than a complex one.
- ahelwer 6y ago
  I have no idea how you could possibly assign probabilities to things like this.
  - ravi-delia 6y ago
    It's the mechanism by which Occam's razor works. A monstrous spaghetti codebase could absolutely produce the universe we see. The problem is that many, many such codebases fit equally well. If you wanted to you could say that the universe just is the way it is, specifying the state completely. But you could always say that, no matter what the universe is! As it turns out though, huge swaths of the universe's behavior can be produced without all that individual specification. There are massive holes in our understanding, but at pretty much every turn for the last few centuries we've gotten better at predicting more stuff with fewer equations. Does that mean it'll continue? No idea! But that's why there's a real sense that a simple universe is more 'probable' than any particular complicated one. Now maybe no simple universe can possibly fit ours, in which case we're just kinda fucked.
    - akiselev 6y ago
      Occam's razor isn't a law of nature, a proven theorem, or even a testable hypothesis. It's a rule of thumb and a poor one for analyzing systems with extreme unknowns like the nature of the universe.
      - ravi-delia 6y ago
        I get why you're saying that, I don't think I explained what I was trying to say well. Occam's razor doesn't say that the universe is simple, only that of two theories that make identical predictions you should choose the simpler. That much makes sense on better grounds than a rule of thumb. You're correct regarding the extreme unknowns, since of all possible universe-rules most are complex. However, should a simple universe-rule correspond with our own, it is more likely to be correct than any single complex universe-rule. More importantly, the whole testable hypothesis thing? That relies heavily on the same intuition. Test results mean nothing if the universe can cheat, and in fact the universe can cheat. But we disregard the billions of possible cheating universes eating the same slice of the probability pie in favor of the non-cheating universe, should it exist.
ruffrey 6y ago
That complicated Java file is a stream of 1s and 0s. The “kinds of things” in a processor that interprets the Java file - also very simple. There is a huge amount of complexity represented by very few distinct types of things.
burntoutfire 6y ago
> What if the universe is actually an enormous java program with a 10,000 line Utils.java file? An enormously complex set of rules is more likely to produce bizarre edge cases/inconsistencies/glitches. So far, we arguably we haven't observed any.
- exdsq 6y ago
  I'm more likely to believe the Universe is made of simple rules rather than any form of intelligence successfully writing a correct 10kloc Java file.
- neonological 6y ago
  Nah you're attributing human error in the construction of these rules as a factor. When humans construct rules at this level of complexity those bugs do appear. However.... These rules we are addressing here weren't constructed by a human. We don't even know if they were constructed at all. It could be a perfect set of rules despite the complexity. I'm more on the side of simplicity just because it seems that way, but technically and logically speaking... there is no evidence at all against what the OP said.
- ur-whale 6y ago
  > So far, we arguably we haven't observed any. From the POV of 19th centure physics, the double-slit experiment was quite the glitch. And one could argue that the consequence of that glitch did not exactly simplify physics.
  - acegopher 6y ago
    The delayed-choice quantum eraser and the Triple Phasor Paradox might be the "glitches" of today's physics.
somethingsome 6y ago
The 'enormous java program with a 10,000 line Utils.java file' is governed by a simple set of rules
- tsimionescu 6y ago
  That's irrelevant, as the program can't be derived from the rules. To understand the behavior of the program (the universe) you need to know both the rules (physical laws) and the source code of the program (physical constants/quantities). This is similar to QM and the Standard Model. QM has a very elegant set of simple rules of motion that describe how particles interact. But there are infinitely many possibile universes that behave according to Schrodinger's equation. To see how our universe behaves, you also need the Standard Model, with its dozens of particles and relationships between them and constants and dimensions. In contrast, String Theory only has one 'particle', the string, and a set of rules. You can derive the Standard Model entirely out of those rules apllied to strings, which some physicists find much more appealing. They even derive gravity the same way, though only for a universe that is not like our own. However, this may all be mathematical sleight of hand, as the rules precisely encode the constants of the standard model, and make no correct new predictions otherwise (they do predict supersimmetry, but that has been experimentally refuted so far, making the rules retreat to higher energies). There's a good chance Wolfram's models will turn up the same way - a new mathematical formalism that, if you plug in all of the constants of the Standard Model, predicts the Standard Model precisely.
  - somethingsome 6y ago
    What an interesting comment, thanks for taking the time to write it. > That's irrelevant, as the program can't be derived from the rules. To understand the behavior of the program (the universe) you need to know both the rules (physical laws) and the source code of the program (physical constants/quantities). This does not remove the fact that the universe could be built from a very few simple laws. (my first and only point in my previous comment) As with softwares, even if we do not know the 'source code' we can infer it. How? By designing experiments. There are then three possibilities: 1. Every experiment confirm our theory, in this case we believe with a certain degree of certitude that the model is a good approximation of the reality, 2. An experiment give results that do not correspond to our model, then we need to change or improve our model, 3. Two experiments on the same phenomenon give contradicting results. We finally found a bug, the behavior is undefined, maybe our universe collapse, maybe we are in a giant simulation and we found a limits of higher floating point numbers. > This is similar to QM and the Standard Model. QM has a very elegant set of simple rules of motion that describe how particles interact. But there are infinitely many possibile universes that behave according to Schrodinger's equation. To see how our universe behaves, you also need the Standard Model, with its dozens of particles and relationships between them and constants and dimensions. I do not see exactly why it is relevant but I would add that the standard model in not enough, lots of things exists in physics where we cannot define an experiment to decide what is the (our) reality. But we do not really care because the realities are somewhat equivalent. > In contrast, String Theory only has one 'particle', the string,... I will not address this comment. I think your point is that physics can be defined experimentally or mathematically and the mathematical version has more chances to be wrong because the minimum set or rules are more arbitrary? > There's a good chance Wolfram's models will turn up the same way - a new mathematical formalism that, if you plug in all of the constants of the Standard Model, predicts the Standard Model precisely. Sure there are chances that string theory and Wolfram's theory are a game of the mind and they are fundamentally flawed. But it is also true that if you chose well your first principles and they are easy enough, if both theories can be used to infer a wide variety of phenomenas, there is a good chance that there is an isomorphism between the first principles and they are equivalent in essence, so why bother, go for the system you believe in, hope to make great discoveries and one day, maybe, your theory will be merged with a better theory, but it is rarely lost. Theories are adapted and improved ;)
twelfthnight 6y ago
Feynman once talked about this eloquently [1] and agreed with you about not making assumption that things are elegant. That said, it's interesting to me that the universe is actually much simpler than it appears, just based on the idea that the information contained in a region of space is proportional to the surface area, _not_ the volume [2]. The larger the area of space we look at, the more the discrepancy grows between how much information we think there is (using our human 3 dimensional intuition with x,y,z for each particle) vs how much there actually is (based on Bekenstein Bound) [3]. [1] https://www.youtube.com/watch?v=yjOV3xgydXE https://www.youtube.com/watch?v=yjOV3xgydXE [2] https://en.wikipedia.org/wiki/Bekenstein_bound https://en.wikipedia.org/wiki/Bekenstein_bound [3] https://en.wikipedia.org/wiki/Surface-area-to-volume_ratio#/media/File:SAV_n3.png https://en.wikipedia.org/wiki/Surface-area-to-volume_ratio#/...
- mushishi 6y ago
  Not directly related, but I find the aforementioned proportionality fascinating as I found recently that the cell size is critically bounded by it: "Therefore, as a cell increases in size, its surface area-to-volume ratio decreases. [...] If the cell grows too large, the plasma membrane will not have sufficient surface area to support the rate of diffusion required for the increased volume. In other words, as a cell grows, it becomes less efficient. One way to become more efficient is to divide; another way is to develop organelles that perform specific tasks. These adaptations lead to the development of more sophisticated cells called eukaryotic cells." Source: https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_General_Biology_(Boundless)/4%3A_Cell_Structure/4.1%3A_Studying_Cells/4.1D%3A_Cell_Size https://bio.libretexts.org/Bookshelves/Introductory_and_Gene...
  - twelfthnight 6y ago
    Is this link your writing? It's very interesting!
    - mushishi 6y ago
      No, unfortunately not! I am reading The Vital Question by Nick Lane, and he tells about the cell size in that book. After I noticed the parent comment (of mine), I just googled some reference to my point.
ur-whale 6y ago
> an enormous java program with a 10,000 line Utils.java file That type of code, in the hands of a gifted programmer (not java) using a decent programming language (not java) can usually be subsumed to less than a 100 lines. There is therefore a good case for looking for simple rules :D
BurningFrog 6y ago
One answer is that elementary particles are incredibly small. So it makes intuitive sense that their behavior would be incredibly simple. There is not room to store and execute 10,000 lines of Java in an electron. Very far from a proof, but this argument makes sense to me.
- tsimionescu 6y ago
  The elementary particles are the objects that the rules operate on, not the rules themselves. This argument makes no sense. Photons are terribly small, but a computer screen can well arrange them so that they move according to extremely complex rules (e.g. the photons coming out of my phone screen are obeying the rules encoded on Hacker News's server).
  - BurningFrog 6y ago
    > The elementary particles are the objects that the rules operate on, not the rules themselves. If that's true, there is a third "rules" entity present when two particles interact. And that's the one we should detect and study. Or maybe I'm talking nonsense. But that's how I think about these things.
    - tsimionescu 6y ago
      It would be interesting if the universe consists of a self-executing computer like you suggest, but I don't think it's a logical necessity for such a thing to exist. The laws of the universe could just be abstract concepts that describe how these particles interact with each other.
superpanic 6y ago
The simple rule running your java program is a NAND-gate.

quux 6y ago

Sounds like he read "Death's End" by Liu Cixin and got inspired.

_Microft 6y ago
Is that the book where aliens forget to fold some dimensions while engineering something and it then rains superstrings onto a planet or something like that?
- ebruchez 6y ago
  They do some folding, but I don't remember the "raining superstrings" part. In any case, it's an incredible trilogy. I loved it and I recommend it.
  - Karsteski 6y ago
    I second this. A Remembrance of Earth's Past is one of the best SciFi series I have ever read. I even reread it a year later, and now a few months after that I wish I had time to reread it again. I got my girlfriend, mother and many friends to read the series as well :)

jhrmnn 6y ago

One argument is that the approximate models of nature we know of (general relativity, electrodynamics) are very simple. So it seems that the underlying unifying theory shouldn’t be some huge complex monstrosity. But maybe it is

hackinthebochs 6y ago

>Why is there forever the assumption that the universe is governed by a simple set of rules? What if the universe is actually an enormous java program with a 10,000 line Utils.java file? For a given set of observations, the simplest set of posits that explain those observations are more likely to be true as there are fewer ways to "bake in" the observations into the model.

analog31 6y ago

I would approach it from the opposite direction. Physics starts with that assumption, not because it is believed to be fundamentally true, but because we're curious about how far that assumption can take us. And while not the same as simplicity per se, there are additional assumptions, such as that the rules are uniform over space and time, and that they concern phenomena that are amenable to naturalistic inquiry. The surprise, and perhaps why it continues to be a pursuit, is just how far it's taken us. My reading of history suggests that in the 17th century, scholars assumed that the inquiry would either run into a dead end, or merge with theology. Neither has happened yet. It certainly doesn't prohibit humanity from dropping any of those rules and exploring the universe in alternate ways, so it's not a great loss if physics sets some boundaries for itself.

patcon 6y ago

> Anyway Wolfram gets a lot of hate but honestly I'm glad that some smart dude is using his financially-independent time to go on wild theoretical excursions I agree! I truly appreciate this man. And he seems kind and well-intentioned when I've watched his videos. The silly mental imagery that I have of him, which I don't intend in a mean-spirited way: that his ego is such that he goes well beyond naval-gazing, beyond even sniffing his own rear, and then leans so far that he's looking up at the stars and the universe from a very different perspective than most everyone else ;)

coliveira 6y ago

In fact it is more probable that the universe started from a very simple set of rules than a very complex java file. There are a lot of assumptions behind a java file, I mean, a huge lot of assumptions. A simple universe is not only more beautiful, but it is also more probable than a complex one.

ahelwer 6y ago
I have no idea how you could possibly assign probabilities to things like this.
- ravi-delia 6y ago
  It's the mechanism by which Occam's razor works. A monstrous spaghetti codebase could absolutely produce the universe we see. The problem is that many, many such codebases fit equally well. If you wanted to you could say that the universe just is the way it is, specifying the state completely. But you could always say that, no matter what the universe is! As it turns out though, huge swaths of the universe's behavior can be produced without all that individual specification. There are massive holes in our understanding, but at pretty much every turn for the last few centuries we've gotten better at predicting more stuff with fewer equations. Does that mean it'll continue? No idea! But that's why there's a real sense that a simple universe is more 'probable' than any particular complicated one. Now maybe no simple universe can possibly fit ours, in which case we're just kinda fucked.
  - akiselev 6y ago
    Occam's razor isn't a law of nature, a proven theorem, or even a testable hypothesis. It's a rule of thumb and a poor one for analyzing systems with extreme unknowns like the nature of the universe.
    - ravi-delia 6y ago
      I get why you're saying that, I don't think I explained what I was trying to say well. Occam's razor doesn't say that the universe is simple, only that of two theories that make identical predictions you should choose the simpler. That much makes sense on better grounds than a rule of thumb. You're correct regarding the extreme unknowns, since of all possible universe-rules most are complex. However, should a simple universe-rule correspond with our own, it is more likely to be correct than any single complex universe-rule. More importantly, the whole testable hypothesis thing? That relies heavily on the same intuition. Test results mean nothing if the universe can cheat, and in fact the universe can cheat. But we disregard the billions of possible cheating universes eating the same slice of the probability pie in favor of the non-cheating universe, should it exist.

ruffrey 6y ago

That complicated Java file is a stream of 1s and 0s. The “kinds of things” in a processor that interprets the Java file - also very simple. There is a huge amount of complexity represented by very few distinct types of things.

burntoutfire 6y ago

> What if the universe is actually an enormous java program with a 10,000 line Utils.java file? An enormously complex set of rules is more likely to produce bizarre edge cases/inconsistencies/glitches. So far, we arguably we haven't observed any.

exdsq 6y ago
I'm more likely to believe the Universe is made of simple rules rather than any form of intelligence successfully writing a correct 10kloc Java file.
neonological 6y ago
Nah you're attributing human error in the construction of these rules as a factor. When humans construct rules at this level of complexity those bugs do appear. However.... These rules we are addressing here weren't constructed by a human. We don't even know if they were constructed at all. It could be a perfect set of rules despite the complexity. I'm more on the side of simplicity just because it seems that way, but technically and logically speaking... there is no evidence at all against what the OP said.
ur-whale 6y ago
> So far, we arguably we haven't observed any. From the POV of 19th centure physics, the double-slit experiment was quite the glitch. And one could argue that the consequence of that glitch did not exactly simplify physics.
- acegopher 6y ago
  The delayed-choice quantum eraser and the Triple Phasor Paradox might be the "glitches" of today's physics.

somethingsome 6y ago

The 'enormous java program with a 10,000 line Utils.java file' is governed by a simple set of rules

tsimionescu 6y ago
That's irrelevant, as the program can't be derived from the rules. To understand the behavior of the program (the universe) you need to know both the rules (physical laws) and the source code of the program (physical constants/quantities). This is similar to QM and the Standard Model. QM has a very elegant set of simple rules of motion that describe how particles interact. But there are infinitely many possibile universes that behave according to Schrodinger's equation. To see how our universe behaves, you also need the Standard Model, with its dozens of particles and relationships between them and constants and dimensions. In contrast, String Theory only has one 'particle', the string, and a set of rules. You can derive the Standard Model entirely out of those rules apllied to strings, which some physicists find much more appealing. They even derive gravity the same way, though only for a universe that is not like our own. However, this may all be mathematical sleight of hand, as the rules precisely encode the constants of the standard model, and make no correct new predictions otherwise (they do predict supersimmetry, but that has been experimentally refuted so far, making the rules retreat to higher energies). There's a good chance Wolfram's models will turn up the same way - a new mathematical formalism that, if you plug in all of the constants of the Standard Model, predicts the Standard Model precisely.
- somethingsome 6y ago
  What an interesting comment, thanks for taking the time to write it. > That's irrelevant, as the program can't be derived from the rules. To understand the behavior of the program (the universe) you need to know both the rules (physical laws) and the source code of the program (physical constants/quantities). This does not remove the fact that the universe could be built from a very few simple laws. (my first and only point in my previous comment) As with softwares, even if we do not know the 'source code' we can infer it. How? By designing experiments. There are then three possibilities: 1. Every experiment confirm our theory, in this case we believe with a certain degree of certitude that the model is a good approximation of the reality, 2. An experiment give results that do not correspond to our model, then we need to change or improve our model, 3. Two experiments on the same phenomenon give contradicting results. We finally found a bug, the behavior is undefined, maybe our universe collapse, maybe we are in a giant simulation and we found a limits of higher floating point numbers. > This is similar to QM and the Standard Model. QM has a very elegant set of simple rules of motion that describe how particles interact. But there are infinitely many possibile universes that behave according to Schrodinger's equation. To see how our universe behaves, you also need the Standard Model, with its dozens of particles and relationships between them and constants and dimensions. I do not see exactly why it is relevant but I would add that the standard model in not enough, lots of things exists in physics where we cannot define an experiment to decide what is the (our) reality. But we do not really care because the realities are somewhat equivalent. > In contrast, String Theory only has one 'particle', the string,... I will not address this comment. I think your point is that physics can be defined experimentally or mathematically and the mathematical version has more chances to be wrong because the minimum set or rules are more arbitrary? > There's a good chance Wolfram's models will turn up the same way - a new mathematical formalism that, if you plug in all of the constants of the Standard Model, predicts the Standard Model precisely. Sure there are chances that string theory and Wolfram's theory are a game of the mind and they are fundamentally flawed. But it is also true that if you chose well your first principles and they are easy enough, if both theories can be used to infer a wide variety of phenomenas, there is a good chance that there is an isomorphism between the first principles and they are equivalent in essence, so why bother, go for the system you believe in, hope to make great discoveries and one day, maybe, your theory will be merged with a better theory, but it is rarely lost. Theories are adapted and improved ;)

twelfthnight 6y ago

Feynman once talked about this eloquently [1] and agreed with you about not making assumption that things are elegant. That said, it's interesting to me that the universe is actually much simpler than it appears, just based on the idea that the information contained in a region of space is proportional to the surface area, _not_ the volume [2]. The larger the area of space we look at, the more the discrepancy grows between how much information we think there is (using our human 3 dimensional intuition with x,y,z for each particle) vs how much there actually is (based on Bekenstein Bound) [3]. [1] https://www.youtube.com/watch?v=yjOV3xgydXE https://www.youtube.com/watch?v=yjOV3xgydXE [2] https://en.wikipedia.org/wiki/Bekenstein_bound https://en.wikipedia.org/wiki/Bekenstein_bound [3] https://en.wikipedia.org/wiki/Surface-area-to-volume_ratio#/media/File:SAV_n3.png https://en.wikipedia.org/wiki/Surface-area-to-volume_ratio#/...

mushishi 6y ago
Not directly related, but I find the aforementioned proportionality fascinating as I found recently that the cell size is critically bounded by it: "Therefore, as a cell increases in size, its surface area-to-volume ratio decreases. [...] If the cell grows too large, the plasma membrane will not have sufficient surface area to support the rate of diffusion required for the increased volume. In other words, as a cell grows, it becomes less efficient. One way to become more efficient is to divide; another way is to develop organelles that perform specific tasks. These adaptations lead to the development of more sophisticated cells called eukaryotic cells." Source: https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_General_Biology_(Boundless)/4%3A_Cell_Structure/4.1%3A_Studying_Cells/4.1D%3A_Cell_Size https://bio.libretexts.org/Bookshelves/Introductory_and_Gene...
- twelfthnight 6y ago
  Is this link your writing? It's very interesting!
  - mushishi 6y ago
    No, unfortunately not! I am reading The Vital Question by Nick Lane, and he tells about the cell size in that book. After I noticed the parent comment (of mine), I just googled some reference to my point.

ur-whale 6y ago

> an enormous java program with a 10,000 line Utils.java file That type of code, in the hands of a gifted programmer (not java) using a decent programming language (not java) can usually be subsumed to less than a 100 lines. There is therefore a good case for looking for simple rules :D

BurningFrog 6y ago

One answer is that elementary particles are incredibly small. So it makes intuitive sense that their behavior would be incredibly simple. There is not room to store and execute 10,000 lines of Java in an electron. Very far from a proof, but this argument makes sense to me.

tsimionescu 6y ago
The elementary particles are the objects that the rules operate on, not the rules themselves. This argument makes no sense. Photons are terribly small, but a computer screen can well arrange them so that they move according to extremely complex rules (e.g. the photons coming out of my phone screen are obeying the rules encoded on Hacker News's server).
- BurningFrog 6y ago
  > The elementary particles are the objects that the rules operate on, not the rules themselves. If that's true, there is a third "rules" entity present when two particles interact. And that's the one we should detect and study. Or maybe I'm talking nonsense. But that's how I think about these things.
  - tsimionescu 6y ago
    It would be interesting if the universe consists of a self-executing computer like you suggest, but I don't think it's a logical necessity for such a thing to exist. The laws of the universe could just be abstract concepts that describe how these particles interact with each other.

superpanic 6y ago

The simple rule running your java program is a NAND-gate.