In The Hitchhiker's Guide to the Galaxy, the book by Douglas Adams, a machine made interstellar travel possible by nudging nature toward extremely improbable, but not impossible, events. A new computer-simulation technique promises to calculate chemical-reaction rates 20 times as fast as before by focusing on chains of events that—on the timescales of molecular motion—are very rare but important.
Computational chemistry uses computers as virtual test tubes. For example, by calculating chemical-reaction rates through simulations based on theory, scientists can predict the performance of potential new catalysts before trying to synthesize them, or they can shed light on phenomena such as the misfolding of proteins that's believed to cause Alzheimer's and other diseases.
Molecules move on timescales of femtoseconds, or millionths of a billionth of a second, says Titus van Erp of the Catholic University in Leuven, Belgium. The majority of these fleeting