15-453 Formal Languages, Automata, and Computation
Lecture 21: Computation Histories
We begin by proving Rice's theorem: by looking at the code of a
Turing machine, we cannot decide any non-trivial property of the language
that it accepts. We then introduce another notion often used to
prove undecidability: computation histories, that is, a list of
configurations a Turing machine goes through during its computation.