Experimental Mathematics Website
http://www.experimentalmath.info

<== This is a picture from the interactive geometry package Cinderella showing the behavior of 10,000 starting values in the rectangle [0,1]x[h-1,h+1], where h is the height of the horizontal line, after six iterations of the algorithm which reflects a point x in the sphere then reflects the outcome in the line and then averages the result y with x. It is an accessible prototype for a remarkable image reconstruction algorithm known variously as Douglas-Ratchford, Lion-Mercier, Fienup's method, and "divide-and-concur." Some related graphics can be generated and displayed at these URLs: Expansion Reflection (wait 30-60 seconds to see the display).

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Once humans have invented something by laying down the rules for its existence, like chess, the theory of numbers, or the Mandelbrot set, the implications and patterns that emerge from the underlying constellation of rules may continue to surprise us. But this does not change the fact that we invented the game in the first place. It just shows what a rich invention it was. As the great eighteenth century philosopher Giambattista Vico said, the only truths we can know for certain are those we have invented ourselves. Mathematics is surely the greatest of such inventions. -- Paul Ernst, from "Is Mathematics Discovered or Invented?", Online article, Linguistic and Philosophical Investigations, 2007, vol. 6, no. 1.

The complete list of quotes is available here.

This website is a repository of information on experimental and computer-assisted mathematics. It is operated by

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Disclaimer and copyright. Material on this site is provided for research purposes only and does not necessarily reflect the views or policies of the author's institutions or any other organization. All material is copyrighted by David H. Bailey (c) 2016.

Math Scholar blog. The "Math Scholar" blog is now online. It contains essays, philosophical musings, interesting quotes and exercises, all in the realm of mathematics, computing and modern science. New items are posted on average every two weeks:

Math Drudge blog (older). This blog was co-authored by Bailey and the late Jonathan Borwein, prior to Borwein's death in August 2016.

Jonathan Borwein Memorial site. In the wake of Jonathan Borwein's untimely death in August 2016, this site contains a blog of remembrances of Jon by family, friends and colleagues, together with a compendium of Jon's publications, talks and reviews of his work by others.

  • Jonathan Borwein website and blog
  • Financial Mathematics website and blog. Bailey, together with his colleagues Marcos Lopez de Prado and Qiji Jim Zhu, operate a website and blog devoted to financial mathematics, overfitting and other abuses of mathematics in the field:

    Additional information, in alphabetical order:

    1. Books. Bailey and Jonathan Borwein (now deceased) have authored numerous books on mathematical and scientific computation. For details on the authors' books on experimental mathematics, see:
    2. Commercial sites. For a list of websites of numerous commercial firms that offer mathematical software and (free) online tools, see the Commercial site page:

    3. Institutional sites. For a list of websites of mathematical societies and journals in the general area of experimental and computational mathematics, see the Institutional site page:
    4. Non-commercial software and tools. For a list of websites of non-commercial organizations that offer mathematical software and (free) online tools, see the Non-commercial site page:
    5. Other sites of interest. For a list of numerous other websites with interesting and useful information relevant to mathematics in general and computational mathematics in particular, see the Other site page:

    6. Software. For some freely downloadable software for experimental math research, see the Software page: