
Is the Universe Made of Math? - csomar
https://www.scientificamerican.com/article/is-the-universe-made-of-math-excerpt/
======
twelvechairs
My view is that the root of this is the quote 'All models are wrong but some
are useful'. I dont think youll get something which descries the universe
completely which is less complex than the universe itself. However maths can
certainly describe parts of the universe more simply (but not completely).

~~~
TelmoMenezes
The question here is wether math is just a description or the thing itself,
independently of the complexity.

------
tpeo
>[...] that our reality isn't just described by mathematics – it is
mathematics, in a very specific sense. Not just aspects of it, but all of it,
including you.

Cue to Whitehead's _" a series of footnotes to Plato"_ quip. Though I think he
was a bit off the mark. People aren't merely talking about Plato, but
unwittingly echoing him. It's kind of like that another quote, this time from
Keynes, about practical men being "slaves" to the opinions of long dead
economists.

------
pron
The philosophy of mathematics[1] is a deep and interesting subject, with a
long history of important contributions by people like Hilbert, Brouwer,
Russel, Wittgenstein, Turing, Quine and Putnam among others. It's very hard to
tell from this short piece whether the author simply subscribes to one of the
famous old positions or makes any new claims, and if so, where those claims
are positioned relative to all the old ones.

EDIT: A quick read of the relevant Wikipedia entry shows that Tegmark's view
is basically good-old mathematical Platonism, with a radical, monistic twist.

EDIT2: A question I would pose to a mathematical Platonist monist like Tegmark
would then be, what is the cardinality of the collection of universes? Brouwer
could reject large infinities only because he insisted that mathematics is
limited by the physical, but if the physical and the mathematical are the
same, I can see no justification for rejecting a large set of universes.

[1]: [https://plato.stanford.edu/entries/philosophy-
mathematics/](https://plato.stanford.edu/entries/philosophy-mathematics/)

[2]:
[https://en.wikipedia.org/wiki/Mathematical_universe_hypothes...](https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis)

------
rocqua
If there is such a thing as an external reality, is there even such a thing as
'meaning' that arises from anything other than relationships to other things?
The only way to describe the human experience outside of the human experience
is by describing all interactions and relations between the constituent parts.

That ignores the issue of how useful this description is. It is easy to
conceive of an external mathematical reality that cannot be fully described
from within. Even with a full description, there is no guarantee the
description is at all useful. If you consider how stumped we are by the
goldbach conjecture, and how simple that is, you realize there are plenty of
mathematical structures that defy understanding.

And then there are the standard crises of maths. Incomputable problems,
paradoxes in informal systems, controversial axioms in formal systems (axiom
of choice), and that final bombshell of Godel's incompleteness theorem. All of
these make math seem less rock-solid. Heck, if the universe is maths, we can't
prove the universe is consistent from within the universe.

~~~
sgt101
Yeah, you need a ladder or something to climb up or pull up and then you will
see things right. Or something.

------
oldandtired
It is funny to see this article today. Overnight, I was considering the
question again of "Is the map the territory or not?" JadeNB refers to this in
their comment.

What a lot of people do not see, including many theoretical physicists is that
mathematics is a "map". It describes reality in a simplistic way, but is not
the reality itself.

twlevechairs26 refers to the quote "All models are wrong but some are useful".
This highlights the fact that all models are maps, incomplete, simplified
descriptions that leave out specific parts or include things that are not part
of the thing being described.

When we get arrogant enough to claim the "truth" in mathematics or science we
have moved into the realm of religion. Mathematics and science helps us get a
handle on trying to understand the physical universe around us. But it will
NEVER, and I repeat this, NEVER give us perfect understanding of the universe
around us. For that perfect understanding would require that we become greater
than the universe around (in effect raising ourselves by our bootstraps to be
God or gods).

So, in may ways, the first question here, "Is the map the territory or not?"
before asking "Is the Universe made of mathematics?"

~~~
jackmott
>But it will NEVER, and I repeat this, NEVER give us perfect understanding of
the universe around us.

How can you be sure?

>or that perfect understanding would require that we become greater than the
universe around (in effect raising ourselves by our bootstraps to be God or
gods).

 _shrug_

------
faragon
Can't wait for someone claiming the universe is made of Rust (the programming
language), and how much better is than being made of C.

~~~
nostrademons
Elon Musk's efforts to break us out of the simulation [1] will be much harder
if he can't find a suitable buffer overflow to exploit.

[1] [https://www.forbes.com/sites/janetwburns/2016/10/13/elon-
mus...](https://www.forbes.com/sites/janetwburns/2016/10/13/elon-musk-and-
friends-are-spending-millions-to-break-out-of-the-matrix/#d7d13035ce17)

~~~
rhapsodic
_> Elon Musk's efforts to break us out of the simulation [1] will be much
harder if he can't find a suitable buffer overflow to exploit_

It's astounding that someone as obviously intelligent as Musk believes in
creationism.

~~~
criddell
If I have a big, fast computer and I simulate a universe by randomly defining
a set of rules and then hit "go" over-and-over-and-over again, if life arises
in one of them is that creationism? Isn't it more correct to say I am
exploring the space of all possible universes to see which ones generate life?

~~~
rhapsodic
_> If I have a big, fast computer and I simulate a universe by randomly
defining a set of rules and then hit "go" over-and-over-and-over again, if
life arises in one of them is that creationism? Isn't it more correct to say I
am exploring the space of all possible universes to see which ones generate
life?_

Both statements would be true.

~~~
criddell
When I multiply 5 and 6 am I creating 30?

~~~
rhapsodic
Could you clarify the point you're trying to make?

------
waiseristy
If you have yet to read Tegmarks book, I highly recommend it. It has a very
layperson style of writing

------
ravenouswolves6
Skip the book (and the article), read the original paper:
[https://arxiv.org/pdf/0704.0646.pdf](https://arxiv.org/pdf/0704.0646.pdf)

IMO, Tegmark has a solid argument that the MUH is more plausible than any of
the other suggested possibilities ([https://www.amazon.com/Why-Does-World-
Exist-Existential/dp/0...](https://www.amazon.com/Why-Does-World-Exist-
Existential/dp/0871403595) is good for the PEQ and much more worth reading
than Tegmark's book).

------
kazinator
I firmly believe it. No evidence contradicts it and it is the simplest
possible explanation for everything: no hidden variables.

~~~
pron
A map may be detailed enough not to leave out any detail, but the simplest
explanation for that still wouldn't be that the map is the territory.

~~~
rocqua
A map that leaves out no details is, by definition, equivalent or 'isomorphic'
to the territory.

Equivalence is a weird concept though. Is the factor group O(3)/SO(3)
equivalent to Z/2Z? As a group, the answer is yes. As transformations of R^3,
most definitely not.

~~~
Retra
A map _can_ have details left out of it, while a territory cannot.

~~~
kazinator
Different maps with different levels of detail can all be separate universes.

------
lisa_henderson
This is fundamentally a religious question. There is nothing wrong with
religion, but you should be aware when you step into the realm of religion.
Whether you think the universe is made of math, or God's will, or it's turtles
all the way down, the presumption contains an element of Faith.

~~~
pron
Philosphical, certainly, but why religious? Not all faith is religious. There
are many definitions of religion[1], but, AFAIK, none equate unprovable
philosophical beliefs with religion. Normally, a religion requires at least
some moral or normative elements (i.e., it should relate in some way to how
_humans_ behave or should behave), which this philosophy lacks.

I've read that the author may have some opinions regarding AI that may be
considered religious, but this particular subject so far seems purely
philosophical to me.

[1]:
[https://en.wikipedia.org/wiki/Definition_of_religion](https://en.wikipedia.org/wiki/Definition_of_religion)

~~~
akvadrako
Well, it's even stronger than most religions in specifying how humans _will_
behave, which of course includes _should_. That's because a mathematical
universe is deterministic and more so, that anything mathematically possible
(self-consistent and so forth) will happen infinite times.

I consider it perfectly justifiable to call it physics, but at this level of
abstraction, it's hard to differentiate it from religion too.

~~~
JadeNB
> Well, it's even stronger than most religions in specifying how humans _will_
> behave, which of course includes _should_.

I think that the 'of course' here is not at all obvious. Economics, for
example, seeks to describe how people _will_ behave, but neither makes nor, I
think, is perceived to offer any description of how they _should_ behave (at
least not in any moral sense).

~~~
akvadrako
I disagree. _should_ is only relevant when there is a choice. Under the MUH,
it's like saying 1+1 _should_ = 3, which is fairly meaningless. Basically, the
MUH answers the _should_ question which is why it qualifies as religion. It's
answer is "it's irrelevant".

~~~
pron
Well, people have literally spent millennia arguing over this. I doubt this
could be resolved in a HN comment :)

Anyway, even a deterministic universe (mathematical, i.e. monistic
Platonistic, or otherwise) is still undecidable/intractable, and so normative
prescriptions may well serve an important role as you don't know their place
in the causal chain.

Of course, you could argue that "importance" is also a subjective measure in a
deterministic universe, and an irrelevant one, but then so is "relevance"
itself.

------
rini17
Can we conceive of universe NOT made of math? Even in Harry Potter there's
aritmancy...

~~~
JadeNB
> Can we conceive of universe NOT made of math? Even in Harry Potter there's
> aritmancy...

But there is a difference between a universe in which math exists, and a
universe that is _made_ of math; and the latter is, I think, a much stronger
requirement. (Unless, indeed, every conceivable universe is made of math, in
which case the requirements have exactly the same strength. :-) )

------
wcoenen
If you are intrigued by this flavor of modal realism then the sci-fi book
"Permutation City" might be a good read.

~~~
posterboy
> In 2050, Paul Durham, a Sydney man having experimented on Copies of himself,
> offers wealthy Copies prime real estate in an advanced supercomputer which,
> according to his pitch, will never be shut down and never experience any
> slowdown whatsoever. Durham predicts that efforts to utilise chaotic effects
> will clash with Copy rights.

> Copy rights

is that a pune?

------
sunstone
The universe is made of information.

------
imploder
No. Math is made of the universe.

~~~
JadeNB
> No. Math is made of the universe.

Given that math can easily describe conditions that aren't realised in any
obvious way in our universe, this seems like a proposition for whose
meaningfulness it would be hard to argue. (Granted, the math we do is
_realised_ in the universe, but of course "the map is not the terrain".)

