Shedding light on electron's structure.

An electron may not be exactly what has been thought since its discovery 100 years ago. According to recent measurements by physicists at Purdue University, West Lafayette, Ind., the tiny particle may not be a simple negative point charge, as scientists often describe it.

Science and engineering students have learned for years that the electron has a constant electronic strength. but now we've seen that this may not be the case," explains David Koltick, professor of physics. His research shows that the electromagnetic force from the electron, or its electronic strength, may increase while moving toward the particle's central core.

According to his data, surrounding the electron's core is a fuzzy "cloud" of virtual particles, which wink in and out of existence in pairs. One particle in the pair is positively charged; the other, negatively charged. The cloud is polarized, meaning that the strong negative charge at the core "pushes" the negatively charged particle in a pair slightly farther away from the core than the positively charged particle. The polarization is strongest toward the center of the cloud.

The polarized pairs essentially cancel each other out so that they do not "add" any net electric charge to the electron, Koltick says, but the cloud plays a key role in how the electromagnetic force...