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by GregarianChild 579 days ago
We know that any theorem that is provable at all (in the chosen foundation of mathematics) can be found by patiently enumerating all possible proofs. So, in order to evaluate AlphaProof's achievements, we'd need to know how much of a shortcut AlphaProof achieved. A good proxy for that would be the total energy usage for training and running AlphaProof. A moderate proxy for that would be the number of GPUs / TPUs that were run for 3 days. If it's somebody's laptop, it would be super impressive. If it's 1000s of TPUs, then less so.
2 comments

> We know that any theorem that is provable at all (in the chosen foundation of mathematics) can be found by patiently enumerating all possible proofs.

Which computer science theorem is this from?

It's a direct consequence of the format of a proof. They're finite-length sequences of a finite alphabet of symbols, so of course they're enumerable (the same algorithm you use to count works to enumerate them).

If you want a computer to be able to tell that it found a correct proof once it enumerates it, you need a bit more than that (really just the existence of automated proof checkers is enough for that).

It’s just an obvious statement. If a proof exists, you will eventually get to it.
Only if we take AC, I guess?
No, this has nothing to do with choice.
I guess it is tautological from the definition of "provable". A theorem is provable by definition if there is a finite well-formulated formula that has the theorem as consequence (https://en.wikipedia.org/wiki/Theorem paragraph theorem in logic)
Not sure it’s a tautology. It’s not obvious that a recursively enumerable procedure exists for arbitrary formal systems that will eventually reach all theorems derivable via the axioms and transformation rules. For example, if you perform depth-first traversal, you will not reach all theorems.

Hilbert’s program was a (failed) attempt to determine, loosely speaking, whether there was a process or procedure that could discover all mathematical truths. Any theorem depends on the formal system you start with, but the deeper implicit question is: where do the axioms come from and can we discover all of them (answer: “unknown” and “no”)?

It's "obvious" in the sense that it's a trivial corollary of the completeness theorem (so it wouldn't be true for second order logic, for example).

Hilbert's program failed in no contradiction to what GP wrote because the language of FOL theorems is only recursively enumerable and not decidable. It's obvious that something is true if you've found a proof, but if you haven't found a proof yet, is the theorem wrong or do you simply have to wait a little longer?

Yeah but width-first immediately gives you the solution for any finite alphabet. So in that sense it is trivial.
The shortcut vs enumeration is definitely enormous right? just take average shannon entropy to the exponent of the length for example will be probably > heat death (or whatever death) of universe on all of human compute (I'm assuming I didn't bother to check but it seems intuitively true by a margin)