Post on 11-Jan-2016
The Imitation GameWhat else did Alan Turing do?
Jeff O’ConnellOhlone College
www.ohlone.edu/people/joconnell
Outline
Ciphers and the Enigma
Machine (early 1940s)
Turing Machines (1936)
The Imitation Game (1950)
Ciphers and the Enigma Machine
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Vigenère Ciphers
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The Enigma Machine
The Enigma MachineUsed to both encode and decode messages.
Initially had 3 wheels that were set each day to a predetermined configuration. (Later, more wheels were added to make it more difficult to crack).
As one key was pressed, another would light up giving the encoded (or decoded) letter.
Was designed so that a letter never mapped to itself.
Δ
Turing Machines
Turing wrote a paper called “On Computable Numbers, with an Application to the Entscheidungsproblem” in 1936.
Turing Machines
Turing wrote a paper called “On Computable Numbers, with an Application to the Entscheidungsproblem” in 1936.
Turing MachineTape – Divided into cells. Each cell contains a
symbol.
A Read/Write Head – Can read and write on the tape and move the tape left and right one (and only one) position at a time.
State Register – Stores the “state” of the machine.
A finite table of instructions.
Video
The Imitation Game
Computing Machinery and Intelligence written in 1950 by Alan Turing.
I propose to consider the question “Can machines think?”
It is played with three people, a man (A), a woman (B), and an interrogator (C) who may be of either sex. The interrogator stays in a room apart front the other two. The object of the game for the interrogator is to determine which of the other two is the man and which is the woman.
We now ask the question, "What will happen when a machine takes the part of A in this game?" Will the interrogator decide wrongly as often when the game is played like this as he does when the game is played between a man and a woman? These questions replace our original, "Can machines think?"
Movie
Further Reading/Watching Alan Turing
The Man Who Knew Too Much: Alan Turing and the Invention of the Computer
Caesar Ciphers https://www.khanacademy.org/computing/computer-science/cryptography/crypt/v/caesar-
cipher
Vigenère Ciphers
https://www.youtube.com/watch?v=9zASwVoshiM
Turing’s paper Computing Machinery and Intelligence
http://www.loebner.net/Prizef/TuringArticle.html
Turing Test
http://www.turing.org.uk/scrapbook/test.html
http://www.washingtonpost.com/news/morning-mix/wp/2014/06/09/a-computer-just-passed-the-turing-test-in-landmark-trial/
Turing Machines
Explained - https://www.youtube.com/watch?v=dNRDvLACg5Q
The Busy Beaver - https://www.youtube.com/watch?v=CE8UhcyJS0I
Thank You!
Jeff O’ConnellOhlone College
www.ohlone.edu/people/joconnell