Notes

Chapter 12: The Principle of Computational Equivalence


Section 8: Undecidability and Intractability

Algorithmic complexity theory Circuit complexity [Classes of] fast algorithms Code 1004600 [Computational complexity of] finding outcomes Computational complexity theory Correspondence systems Density of difficult problems Examples of undecidability Functions [computed by Turing machines] Growth rates [of halting times] Halting problems History [of computational complexity theory] History [of undecidability] Implementation [of TM cellular automaton] [Intractability in] systems of limited size Longest halting times [in Turing machines] Lower bounds [on computational complexity] Mathematical impossibilities Multiway tag systems Non-deterministic Turing machines NP completeness [NP completeness in] natural systems [One-sided] Turing machines P completeness P versus NP questions Proofs of undecidability Properties [of example Turing machines] Quantum computers Rule 30 inversion Satisfiability [emulating Turing machines] Sequence equations Sorting networks [Turing] machine 1507 [Turing] machine 600720 Undecidability and sets Undecidability in cellular automata Undecidability in Mathematica [Undecidability in] natural systems Undecidability in tiling problems Word problems

From Stephen Wolfram: A New Kind of Science [citation]