Chemists have made real advances towards the realization of three-dimensional optical data storage. Chemical and Engineering News (dyes that absorb two photons at infrared wavelengths and emit one photon at a higher wavelength. This is desirable because infrared lasers can penetrate more deeply into a medium than visible lasers. Using confocal scanning laser microscopy, Prasad [...]

When scientists make observations of matter, they in most cases observe large numbers of molecules and base their conclusions about a “typical” molecule on the results. Inherent in this fundamental approach is an averaging process. This can be illustrated by the following “thought experiment.” Imagine a can containing millions of dice. Each die in the [...]