Gregory J. Chaitin

"Metabiology": Chaitin, whose version of algorithmic information theory revealed the full extent of the limitations of pre-Gödel and pre-Turing mathematics, in these remarkable 123 pages and in his usual free-wheeling ("creative") way describes a mathematical model for investigating the theoretical effectiveness of Darwinian evolution. In the model, the genomes of organisms take the form of the bit-sequences of certain computer programs, and fitness for survival is represented by the computational power (precisely defined) of those programs. Chaitin has proved that the time complexity for the process of producing higher-"fitness" programs is between N^2 and N^3 when the process is one of cumulative random mutations, this being vastly better than that (2^N) for non-cumulative random mutations and almost as good as that (N) for the imaginary limit of "intelligent design".… (mais)