Illustrating the unusual way things work on the nanoscale, scientists have designed a new nanoelectromechanical system (NEMS) that produces mechanical motion due to the interactions between electrons—yet unlike similar systems, this system does not require any electric current. Instead, the electron-electron interactions couple two electron reservoirs of different temperatures, which generates a heat flow between…
The Case for Co-Decaying Dark Matter
There isn’t as much dark matter around today as there used to be. According to one of the most popular models of dark matter, the universe contained much more dark matter early on when the temperature was hotter. As the universe cooled, the dark matter annihilated away, at least up until a point when thermal…