Perl helps prove universality of 2, 3 Turing machine

Tom Moertel — Fri, 26 Oct 2007 13:23:00 -0400

Alex Smith, a 20-year-old EE student in the UK, proved that the 2, 3 Turing machine is universal. In doing so, he was able to claim the $25,000 prize that Stephen Wolfram offered for the first proof (or disproof) of the 2, 3 machine’s universality.

This story has been getting a lot of attention lately, but one part of the story has not: that the Perl programming language is featured in the proof. In his documentation of the proof, Universality of Wolfram’s 2, 3 Turing Machine, Smith wrote, “I have written several Perl programs, to demonstrate the constructions given in the proof and to interpret the systems given in various conjectures.” Smith’s proof includes no fewer than 7 Perl programs.

Go Perl!

Tom Moertel's Weblog: Tag proof

Perl helps prove universality of 2, 3 Turing machine