somervta comments on FAI Research Constraints and AGI Side Effects - Less Wrong

14 Post author: JustinShovelain 03 June 2015 07:25PM

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Comment author: jessicat 03 June 2015 10:02:59PM *  13 points [-]

This model seems quite a bit different from mine, which is that FAI research is about reducing FAI to an AGI problem, and solving AGI takes more work than doing this reduction.

More concretely, consider a proposal such as Paul's reflective automated philosophy method, which might be able to be implemented using epsiodic reinforcement learning. This proposal has problems, and it's not clear that it works -- but if it did, then it would have reduced FAI to a reinforcement learning problem. Presumably, any implementations of this proposal would benefit from any reinforcement learning advances in the AGI field.

Of course, even if we a proposal like this works, it might require better or different AGI capabilities from UFAI projects. I expect this to be true for black-box FAI solutions such as Paul's. This presents additional strategic difficulties. However, I think the post fails to accurately model these difficulties. The right answer here is to get AGI researchers to develop (and not publish anything about) enough AGI capabilities for FAI without running a UFAI in the meantime, even though the capabilities to run it exist.

Assuming that this reflective automated philosophy system doesn't work, it could still be the case that there is a different reduction from FAI to AGI that can be created through armchair technical philosophy. This is often what MIRI's "unbounded solutions" research is about: finding ways you could solve FAI if you had a hypercomputer. Once you find a solution like this, it might be possible to define it in terms of AGI capabilities instead of hypercomputation, and at that point FAI would be reduced to an AGI problem. We haven't put enough work into this problem to know that a reduction couldn't be created in, say, 20 years by 20 highly competent mathematician-philosophers.

In the most pessimistic case (which I don't think is too likely), the task of reducing FAI to an AGI problem is significantly harder than creating AGI. In this case, the model in the post seems to be mostly accurate, except that it neglects the fact that serial advances might be important (so we get diminishing marginal progress towards FAI or AGI per additional researcher in a given year).

Comment author: [deleted] 04 June 2015 03:12:38PM 0 points [-]

This is often what MIRI's "unbounded solutions" research is about: finding ways you could solve FAI if you had a hypercomputer.

Sorry to criticize out of the blue, but I think that's a very bad idea. To wit, "Assume a contradiction, prove False, and ex falso quodlibet." If you start by assuming a hypercomputer and reason mathematically from there, I think you'll mostly derive paradox theorems and contradictions.

Comment author: somervta 05 June 2015 12:01:22AM 1 point [-]

Why do you think that a hypercomputer is inherently contradictory?

Comment author: [deleted] 05 June 2015 12:07:14AM *  0 points [-]

A hypercomputer is a computer that can deterministically decide the Halting Problem for a Turing machine in finite time. We already know that this is physically impossible.

And unfortunately, most of the FAI work I've seen under the assumption of having a hypercomputer tends to end up along the lines of, "We started by assuming we had a Turing Oracle, and proved that given a second-level Turing Oracle, we can implement UDT with blah blah blah."

Comment author: somervta 05 June 2015 12:41:51AM 1 point [-]

We don't know that it's physically impossible, although it does look that way, but even if we did that doesn't mean it's contradictory, not to the extent that using it you'll "mostly derive paradox theorems and contradictions".

Comment author: [deleted] 05 June 2015 02:33:04PM 1 point [-]

If Turing oracles are not physically impossible, then we need an explanation for how physics implements an infinite tower of Turing oracle levels. Short of that, I'm going to believe Turing oracles are impossible.

even if we did that doesn't mean it's contradictory, not to the extent that using it you'll "mostly derive paradox theorems and contradictions".

If you start with something undecidable and build on it, you usually find that your results are even more undecidable (require a higher level of Turing oracle). There's also the AIT angle, which says that a true Turing oracle possesses infinite Kolmogorov complexity, and since Shannon entropy is the expected-value of Kolmogorov complexity, and Shannon entropy is closely related to physical entropy... we have strong reason to think that a Turing oracle violates basic thermodynamics.

Comment author: somervta 06 June 2015 10:28:19PM *  1 point [-]

Why do we need the full tower? Why couldn't it be the case that just one (or some other finite number) of the Turing Oracle levels are physically possible?

Comment author: [deleted] 07 June 2015 12:48:18AM *  0 points [-]

Effectively, there is either some natural number n such that physics allows for n levels of physically-implementable Turing oracles, or the number is omega. Mostly, we think the number should either be zero or omega, because once you have a first-level Turing Oracle, you construct the next level just by phrasing the Halting Problem for Turing Machines with One Oracle, and then positing an oracle for that, and so on.

Likewise, having omega (cardinality of the natural numbers) bits of algorithmic information is equivalent to having a first-level Turing Oracle (knowing the value of Chaitin's Omega completely). From there, you start needing larger and larger infinities of bits to handle higher levels of the Turing hierarchy.

So the question is: how large a set of bits can physics allow us to compute with? Possible answers are:

  • Finite only. This is what we currently believe.
  • Countably infinite (Alef zero) or Continuum infinite (Alef one). Playing time-dilation games with General Relativity might, in certain funky situations I don't quite understand but which form the basis of some science fiction, almost allow you to get up to here. But it would require negative energy or infinite mass or things of that nature.
  • Arbitrarily large infinities. Almost definitely not.
  • Omega: if we're completely wrong about the relationship between computation and physics as we know it, possible.