Important information regarding the recent AMS power outage.

The transformer that provides electricity to the AMS building in Providence went down on Sunday, April 22. The restoration of our email, website, AMS Bookstore and other systems is almost complete. We are currently running on a generator but overnight a new transformer should be hooked up and (fingers crossed) we should be fine by 8:00 (EDT) Wednesday morning. This issue has affected selected phones, which should be repaired by the end of today. No email was lost, although the accumulated messages are only just now being delivered so you should expect some delay.

Thanks for your patience.

Mathematical Digest

Short Summaries of Articles about Mathematics
in the Popular Press

"Computing at the Edge: Capturing a flame's flicker, an ink jet's splatter,and other shifting shapes," by Ivars Peterson. Science News, 10 April1999, pages 232-234.

The surface of a breaking wave is jagged and rapidly changing. It is an ofexample turbulent behavior that can result from forces acting at the boundarybetween two different materials. This complicated behavior is difficult todescribe mathematically. This article describes a new approach being used tomodel such situations. Called the level-set approach, it involves modeling thetwo-dimensional boundary as part of a three-dimensional surface. It turns outthat from the three-dimensional perspective, the changes in the boundary aresmoother. The method is being used to detect edges in scanned medical images,model the growth of crystals, and create special effects for movies.

--- Elizabeth Moisan

American Mathematical Society