It's arguably ~2500 years old, dating back to the Pythagoreans, who believed that "all is number" and had a very large and complex system of musical rituals.

The modern manifestation is mostly the intellectual product of Konrad Zuse, who wrote "digital physics" in 1969.

> https://en.wikipedia.org/wiki/Digital_physics

Wolfram, Tegmark, Bostrom, etc. are mostly downstream of Zuse.