A Universal Turing Machine

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A Universal Turing Machine Costas Busch - RPI

A limitation of Turing Machines: Turing Machines are “hardwired” they execute only one program Real Computers are re-programmable Costas Busch - RPI

Universal Turing Machine Solution: Universal Turing Machine Attributes: Reprogrammable machine Simulates any other Turing Machine Costas Busch - RPI

Three tapes Description of Universal Turing Machine Tape Contents of State of Costas Busch - RPI

A Turing Machine is described with a binary string of 0’s and 1’s Therefore: The set of Turing machines forms a language: each string of the language is the binary encoding of a Turing Machine Costas Busch - RPI

Language of Turing Machines 00100100101111, 111010011110010101, …… } (Turing Machine 2) …… Costas Busch - RPI