Interesting. I wonder if it might be possible to prove the existence of fixed points of compression programs using only general assumptions (which would be sat

Interesting. I wonder if it might be possible to prove the existence of fixed points of compression programs using only general assumptions (which would be satisfied by the Lempel-Ziv implementations the author discusses so well). Such a fixed-point theorem would probably not tell us how to find solutions but it would be illuminating if the assumptions could be made weak enough.