# Mathematical Digest

### Short Summaries of Articles about Mathematics

in the Popular Press

"Lava lamp randomness," by Ivars Peterson. *Science News*, 9 August 1997,page 92.

The "lava lamp" has become a kitsch icon of the 1970s. Now, researchers haveturned to the meandering, unpredictable movements of a lava lamp's coloredblobs in order to improve random number generators. Such generators producerandom numbers by carrying out a set of procedures on a "seed number"; if fedthe same seed number a second time, the generator will produce the same stringof digits. Varying the seed numbers is therefore important. The movements ofthe blobs in the lava lamp were an inspiration for researchers to come up witha new way of randomly varying the seed numbers.

*--- Allyn Jackson*