When we hear the word number, symbols like 1,,¼, π (area enclosed by a unit circle), ι (symbol for ), ε (infinitesimal), ω (ordinal infinity), ℵ (cardinal infinity), …. 173 more words

## Tags » Computability

#### A Proof Of The Halting Theorem

*Toward teaching computability and complexity simultaneously*

Wilhelm Ackermann was a mathematician best known for work in constructive aspects of logic. The… 1,007 more words

#### Hector Zenil

I’ve run across some of his work before, but I ran into some new material by Hector Zenil that will likely interest those following information theory, complexity, and computer science here. 482 more words

#### Knowledge and Total Functions

In the article SKETCH OF A PROOF: COMPUTABLE TOTAL FUNCTIONS ARE NOT ENUMERABLE I have used the notion of “total functions”. What is so special about “total functions”? 752 more words

#### Church and Turing

Alonzo Church (left) and Alan Turing (right)

Alan Turing is no doubt the most well-known of all computer scientists. His Turing machine is justly famous, and the video below shows a really cool… 560 more words