Alan Turing
Enigma
Chris Jager
Contents
Introduction
Childhood & Youth
The Turing Machine
Second World War
Turing Test
Turing’s Death
References
Questions
Introduction
Paper not finished (yet)
A lot of information about the works
of Turing
Less information about the person
itself
Childhood & Youth (1)
Father, Julius Mathison Turing,
Indian Civil Service
Mother, Ethel Sarah Stoney,
daughter of chief engineer of the
Madras Railways
Brother, John Turing, London
solicitor
Alan Turing, born at 23rd of june,
1912
Childhood & Youth (2)
Father went to India
Grown up in different kind of families
First Science book resulted in
experiments
“If he is to be solely a Scientific
Specialist, he is wasting his time at a
Public School “
Turing Machine (1)
Christopher Morcom’s death
1931 King’s College
“Could there exist, at least in
principle, a definite method or
process by which it could be decided
whether any given mathematical
assertion was provable”
Turing Machine (2)
Kurt Gödel :
• “Any consistent system cannot be used
to prove its own consistency“
• “In any consistent formalization of
mathematics that is sufficiently strong
to define the concept of natural
numbers, one can construct a statement
that can be neither proved nor
disproved within that system“
Turing Machine (3)
1: A tape which is divided into cells,
one next to the other.
2: A head that can read and write
symbols on the tape and move left
and right.
3: A state register that stores the
state of the Turing machine
4: An action table (or transition
function)
Turing Machine (4)
Universal Turing Machine
Programs
Paper in 1936: no method could decide
whether an assertion is provable, “On
Computable Numbers, with an Application
to the Entscheidungsproblem” at
Princeton University
Lambda-calculus of Church
Church-Turing thesis: “
Turing Machine (5)
Church-Turing thesis: “Any computer
program in any of the conventional
programming languages can be
translated into a Turing machine,
and any Turing machine can be
translated into most programming
languages, so the thesis is equivalent
to saying that the conventional
programming languages are
sufficient to express any algorithm”
Turing Machine (6)
Mechanical Turing Machine
http://www.igs.net/~tril/tm/tm.html
Second World War (1)
1918 Arthur Scherbius built the
Enigma
Before that, all coding systems were
lingual based
Advantage Enigma: Enigma machine
useless when stolen, cypher
produced was very difficult
Polish were good at cracking codes
Second World War (2)
Second World War (3)
Polish enable to crack the code
Bought a commercial Enigma
Called for help: mathematicians
The French bought keys, couldn’t do
anything with it
Poland foresaw its invasion by
Germany: gave all knowledge to
England and France, destroyed it
afterwards (1939)
Second World War (4)
Enigma machine exists out of:
• Plugboard
• 3/ 4/ 5 rotors
• “mirror” rotor
• http://www.enigmaco.de/
Second World War (5)
1939 Turing was asked to help to crack the
Enigma
Built with a team the Colussus, the first
programmable computer
Based on:
• his own 1936 concept of the universal machine
• the potential speed and reliability of electronic
technology
• the inefficiency in designing different machines for
different logical processes
Cyphercode could be decrypted from 1943
All computers were destroyed, ordered by
Churchill
Second World War (6)
Second World War (7)
Second World War (8)
Turing Test (1)
Because of the construction of the
Colussus Turing thought it could be
possible to construct a computer with the
mind of a human being
Wasn’t focused anymore on what a TM
could NOT do, but could do
“Turing was convinced that if a computer
could do all mathematical operations, it
could also do anything a person can do, a
still highly controversial opinion“
Turing Test (2)
Manchester University
Neurology & physiology
Neville Johnson
Turing liked running very much: he
even ran the Marathon
http://www-history.mcs.st-
andrews.ac.uk/history/Miscellaneous
/Turing/Running.html
Turing Test (3)
1950 “Computing Machinery and
Intelligence”
Turing Test
2000 a computer could pass
Round 1990 no computer came near
breaking through the test, and still
there isn’t any computer who can
Turing Test (4)
Focused more on biology
Used computers for his equations
First one who used computers for
that purpose
Turing’s Death
Arrested for being homosexual
Accepted a year being treated with
oestrogen
Because of Cold War he was
excluded from main projects
He wasn’t accepted anymore
Committed suicide by eating a
cyanide poisoned apple, 8th of June
1954
References
http://artzia.com/History/Biography/
Turing/
http://www.turing.org.uk/bio/part1.h
tml
http://www-history.mcs.st-
andrews.ac.uk/history/Miscellaneous
/Turing/Running.html
http://www.enigmaco.de/
Questions?