gwern comments on What if AI doesn't quite go FOOM? - Less Wrong
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How do we know this is far off? For some very useful processes we're already close to optimal. For example, linear programming is close to the theoretical optimum already as are the improved versions of the Euclidean algorithm, and even the most efficient of those are not much more efficient than Euclid's original which is around 2000 years old. And again, if it turns out that the complexity hierarchy strongly does not collapse then many algorithms we have today will turn out to be close to best possible. So what makes you so certain that we can see that reaching optimality limits is far off?
If linear programming is so close to the optimum, why did we see such massive speedups in it and integer programming over the past few decades? (Or are you saying those speedups brought us almost to the optimum?)
There are a variety of things going on here. One is that those speedups helped. A major part those is imprecision on my part. This is actually a good example of an interesting (and from the perspective of what is discussed above) potentially dangerous phenomenon. Most of the time when we discuss the efficiency of algorithms one is looking at big-O bounds. But those by nature have constants built into them. In the case of linear programming, it turned out that we could drastically improve the constants. This is related to what I discussed above where even if one has P != NP, one could have effective efficient ways of solving all instances of 3-SAT that have fewer than say 10^80 terms. That sort of situation could be about as bad from a FOOM perspective. To the immediate purpose being discussed above, the Euclidean algorithm example is probably better since in that case we actually know that there's not much room for improvements in the constants.