[BITList] Happy Birthday, Turing's universal machine
John Feltham
wulguru.wantok at gmail.com
Tue Nov 18 11:39:26 GMT 2008
Begin forwarded message:
Happy Birthday, Turing's universal machine
Solving the unsolvable
By Phil Manchester • Get more from this author
Posted in Science, 18th November 2008 00:21 GMT
It's just 71 years ago this month that a seminal paper from Alan
Turing was published, which helped pave the way to today's multi-
billion dollar IT industry and confer on Turing the title of father of
modern computer science.
As is often the case in scientific endeavour, Turing was actually
working on an entirely different task when he stumbled on a way to
create a general-purpose computer.
The paper that encapsulated this machine? On Computable Numbers with
an Application to the Entscheidungsproblem.
The Entscheidungsproblem - which translated from German literally
means "decision problem" - referred to a mathematical challenge laid
down by German mathematician David Hilbert.
The Entscheidungsproblem goes to the very heart of Hilbert's thoughts
on the nature of mathematics. At the start of the twentieth century
deep questions were being asked about science and the tools used to
think about scientific problems. In the same way that Einstein's work
had challenged orthodox views of physics, so Hilbert and others
questioned mathematics.
Hilbert posed three fundamental questions: is mathematics "complete",
is it "consistent," and - the Entscheidungsproblem - is it
"decidable". The first two were answered - negatively - in 1931 by the
Austrian mathematician Kurt Godel.
Turing scuppered Hilbert's final question with his 1937 paper although
the American mathematician Alonzo Church - later Turing's professor at
Princeton - came up with a similar negative analysis a year earlier.
The two approaches are generally combined as the Church-Turing Theorem.
Turing's real insight was, of course, the concept of a "Universal (or
Turing) machine." He conceived the Universal Machine as a way to
demonstrate that it was impossible to solve the Entscheidungsproblem.
But he had also stumbled on what was effectively the blue print for a
general-purpose computer and this almost certainly justifies his
status as the founder of modern computing.
Copies of Turing's original paper are available online both in
facsimile and in text form. ®
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.bcn.mythic-beasts.com/pipermail/bitlist/attachments/20081118/8007a068/attachment-0001.shtml
More information about the BITList
mailing list