Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
2/4/09 9:49 AMCryptanalyze This -New York Times Page 1 of 3http://query.nytimes.com/gst/fullpage.html?res=9E02E7DA1138F934A35752C1A96F958260&sec=&spon=&pagewanted=print
 

Summary: 2/4/09 9:49 AMCryptanalyze This - New York Times
Page 1 of 3http://query.nytimes.com/gst/fullpage.html?res=9E02E7DA1138F934A35752C1A96F958260&sec=&spon=&pagewanted=print
November 7, 1999
Cryptanalyze This
By ROBERT OSSERMAN
THE CODE BOOK
The Evolution of Secrecy
From Mary Queen of Scots
to Quantum Cryptography.
By Simon Singh.
Illustrated. 402 pp. New York:
Doubleday. $24.95.
A very old joke -- one that does not quite work in written form -- goes, ''If 9W is the answer, what is the
question?'' One reason mathematicians are fond of this joke (whose punch line is below) is that it is a
perfect example of an ''inverse problem,'' one that arises when one knows the outcome of some process and
needs to deduce what led to it. Coding and decoding -- or in Greek terminology, cryptography and
cryptanalysis -- are perfect examples of direct and inverse problems. They share the basic features of both:
the inverse problem is generally far more difficult to solve, and there may not be a unique answer. A direct
operation playing a major part in current cryptography involves multiplying together two large numbers.
The inverse takes the resulting even larger (say, 300-digit) number and tries to factor it to find the original

  

Source: Akhmedov, Azer - Department of Mathematics, University of California at Santa Barbara

 

Collections: Mathematics