Nondeterministic Turing Machines were introduced very early and became the basis for the Church/Turing Thesis. An important complexity result is that in impor

Nondeterministic Turing Machines were introduced very early and became the basis for the Church/Turing Thesis. An important complexity result is that in important applications, a digital implementation can be hundreds of times faster that a parallel lambda expression. Consequently, the lambda calculus cannot be a practical foundation for computing. See the following for more information: "An Actor Application Can Be Hundreds of Times Faster Than a Parallel Lambda Expression" https://professorhewitt.blogspot.com/2021/03/an-actor-application-can-be-hundreds-of.html https://professorhewitt.blogspot.com/2021/03/an-actor-applic...