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Build a Turing Machine emulator

to explore Turing’s great ideas

Lego Turing Machine

A precise definition ofcomputation

Alonzo Church

Computation = λ CalculusChurch Thesis (Apr 1936)

Kurt Godel

“Thoroughly unsatisfactory”

Alan Turing

http://www.kurzweilai.net/passing-of-the-typewriter

Computation = Turing Machine

Turing’s Thesis (Nov 1936)

Kurt Godel

“That this really is the correctdefinition of mechanicalcomputability was establishedbeyond any doubt by Turing.”

A universal machine

“It is possible to invent asingle machine which can beused to compute anycomputable sequence.”

“If it should turn out that the basic logics of a machinedesigned for the numerical solution of differential equationscoincide with the logics of a machine intended to make bills fora department store, I would regard this as the most amazingcoincidence that I have ever encountered.” –Howard Aiken in 1956

http://www.rdrop.com/ half/General/UTM/UTMStateTable.html

Program = Data

Automatic Computing Engine,proposed in 1946 and built in 1950

Turing’s Great Ideas:• Turing machines as a model for computation• A single machine can emulate all others• Programs as data for other programs

Turing’s Great Ideas:• Turing machines as a model for computation• A single machine can emulate all others• Programs as data for other programs

Further readings: