Implementing an Unpractical Turing Machine Using Return-Point Memory

Abstract

Turing complete machines can imitate all other computational machines including themselves. Although building such a machine sounds daunting, according to Alan Turing: “A man provided with paper, pencil, and eraser, and subject to a strict discipline, is in effect a universal machine”. We take his words to the letter, and propose a new realization of a universal machine utilizing a purely mechanical form of memory; return-point memory. Our machine consists of an Instron testing machine, a couple nitinol wires and a disciplined human operator following a small set of simple instructions. We will demonstrate the remarkable power of abstraction underlying Turing machines, and discuss the experimental limitations of our machine, demonstrating its rather unpractical use as a computer but practical nature as a teaching tool.