Series Expedition
Turing Machine
Trace computation from its historical prelude through its minimal structure, mechanical translation, a demonstrator, universal machines, and the limits of computability.
Suggested route
Follow a sequence that connects progressively deeper views of the same subject.
Prelude · AvailableTuring-Welchman Bombe
See the electromechanical Bombe that supported Enigma codebreaking at Bletchley Park as a historical prelude to abstract computation.
1/4 · AvailableConcept Machine
Observe one instruction through the minimal structure of tape, head, state, and rules in five phases.
2/4 · AvailableMechanism Bridge
Translate the Concept Machine’s five phases into paper tape, a reading head, rule selector, writing punch, drive wheel, and state lamps.
3/4 · AvailableMechanical Demonstrator
Follow a mechanical GLB demonstrator in which a timing shaft, state drum, rule register, punch, and gears move together.
4/4 · AvailableUniversal Machine
Move from storing programs on tape to universal machines and the entrance to the halting problem.