From mab@crypto.com Wed May 12 13:26:04 1993
I don't see how determining that a particular string is an encrypted message reduces to the halting problem.
Consider that the cyphertext is a program for an abstract machine called the cyphercracker which returns TRUE if a message is encoded otherwise FALSE. Such a system for determining message-ness could take an arbitrary amount of cpu time and no amount of static analysis could determine the return value quicker.
Paul E. Baclace peb@procase.com
Well, that formulation is a bit fuzzy, but I think you've got your reduction technique backwards. To reduce something to the halting problem, you need to show that you could use a machne that solves your problem to solve halting, not the other way around. -matt