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[TI] Compact: Improve section on Kolmogorov complexity proofs
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@@ -62,11 +62,13 @@ where the Program doesn't have to compile, i.e. we can describe processes inform
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\stepLabelNumber{theorem}
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\stepLabelNumber{theorem}
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\fancytheorem{Prime number} $\displaystyle \limni \frac{\text{Prime}(n)}{\frac{n}{\ln(n)}}$
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\fancytheorem{Prime number} $\displaystyle \limni \frac{\text{Prime}(n)}{\frac{n}{\ln(n)}}$
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\fhlc{Cyan}{Proofs} Most of the proofs start with defining the number of words of exactly the required length and we can then usually deduce some kind of indirect proof
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\fhlc{Cyan}{Proofs} Proofs in which we need to show a lower bound for Kolmogorov-Complexity (almost) always work as follows:
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(using the fact that there are at most $2^k - 1$ words $x$ with $K(x) < k$).
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Assume for contradiction that there are no words with $K(w) > f$ for all $w \in W$.
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We count the number $m$ of words in $W$ and the number $n$ of programs of length $\leq f$ ($f$ being the given, lower bound).
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We will have $m - n > 0$, which means, there are more different words than there are Programs with Kolmogorov-Complexity $\leq f$,
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which is a contradiction to our assumption.
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It is useful to remember the laws of logarithm and the fact that there are $\floor{\frac{n}{k}} + 1$ numbers divisible by $k$ in the set $\{ 0, 1, \ldots, n \}$.
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There are $\floor{\frac{n}{k}} + 1$ numbers divisible by $k$ in the set $\{ 0, 1, \ldots, n \}$.
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Additionally, the pigeonhole principle can come in very handy
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\shade{Orange}{Laws of logarithm}
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\shade{Orange}{Laws of logarithm}
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\drmvspace
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\drmvspace
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