Complexity research tries to apply absolute numbers to the question regarding how complex a data sequence is, which in turn has something to say about how well the sequence will compress. Traditional data compression research dodges the question of absolute complexity, instead always referring to the entropy of a data stream “with respect to a given model.” Complexity studies the entropy of a sequence with respect to God’s model.

# Andrei Nikolaevich Kolmogorov

This site is dedicated to the Centennial of Andrei Nikolaevich Kolmogorov, a leading light in the field of complexity. The site contains the information for a conference being held in his honor in Moscow during June, 2003.

# Kolmogorov Complexity

The definition from the NIST Dictionary of Algorithms and Data Structures.

http://www.nist.gov/dads/HTML/kolmogorov.html

# Wikipedia Entry: Algorithmic Information Theory

The Wikipedia entry for Algorithmic Information Theory. Explains the field of study that includes such interesting things as Kolmogorov complexity.

http://en.wikipedia.org/wiki/Algorithmic_information_theory

# Data Compression Newsletter #20 - Randomness and Complexity

This issue of the newsletter talks about randomness, complexity, and a long-time favorite, recursive compression.

http://www.ddj.com/documents/s=1539/ddj0107cm/0107cm001.htm

# Complexity International

Complexity International is a refereed journal for scientific papers dealing with any area of complex systems research.

# Information Content and Compression Limit FAQ

How much can a given piece of data be compressed? This FAQ addresses that question, including some necessary critiques of the question itself. Graham Fyffe apparently spends some time thinking about complexity.

http://www.geocities.com/CollegePark/9315/infofaq.htm

# G J Chaitin

G.J. Chaitin seems to be interested in complexity and information theory.

http://www.cs.auckland.ac.nz/CDMTCS/chaitin/

# Kolmogorov, Andrey Nikolayevich

A short bio of the famous Russian mathematician. His name lives on in comp.compression and elsewhere due to his seminal work in the study of complexity.

http://www.dam.brown.edu/people/yiannis/kolm.html