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Comment by nyrikki

8 months ago

I will admit that I added that cite mostly because of the very real barriers to even learning RUSS.

By the typos etc.. you. can probably also tell I was doing this on mobile, unfortunately as a passenger in a car.

To quote Chaitin’s explanation here:

> In contrast I would like to measure the power of a set of axioms and rules of inference. I would like to be able to say that if one has ten pounds of axioms and a twenty-pound theorem, then that theorem cannot be derived from those axioms.

This paper's notation does seem to be confusing, but I still think it is essentially complete with the above.

"K_{ℱ_{QG}}" would probably most commonly be L in most descriptions, a natural number that is the upper bound of complexity for provable statements in a formal system S

L is not a limit on complexity, it means that there is no formal proof for S that its Kolmogorov complexity exceeds L, for any string.

You can still prove that there are strings far more complex than L with S, and in fact there will often be far more of those strings than the ones equal to or less than L.

It is a limit on what you can prove about those strings with a greaterKolmogorov complexity in S.

Or to rewrite the above:

"There exists a natural number L such that we can't prove the Kolmogorov complexity of any specific string of bits is more than L."

Does that help or did I miss the mark on your objection?

Their notation of “ K_{ℱ_{QG}}” wasn’t a problem. Seems a reasonable name for a constant associated with Kolmogorov complexity and a formal system which they’ve named ℱ_{QG}.

The issue is that what they said seemingly was not

"There exists a natural number L such that we can't prove the Kolmogorov complexity of any specific string of bits is more than L."

But

"There exists a natural number L such that we can't prove (in ℱ_{QG}) any statement S whose complexity is more than L.",

which is wrong.

They later go on to say “These strings cannot be generated by programs of length <= n, and hence cannot correspond to provable statements in ℱ_{QG}.” which follows from the previous wrong statement but doesn’t follow from the accurate statement you gave, which seems to suggest that they really did mean the inaccurate statement that they wrote, not the correct one you wrote.