Physicists Probe The Deep Earth For A Fifth Fundamental Force
Interactions NASAElectrons' spin may give rise to a force that allows particles to interact over very long distances. In general, people tend to use the phrase "force of nature" loosely, as in "she's a real force of nature." But physicists are pickier--they reserve the phrase for just four separate, universal forces they call the "fundamental forces": gravity, electro-magnetism, and the strong and weak nuclear forces, which hold the nucleus together and are involved with radioactive decay, respectively. That doesn't mean physicists rule out the possibility that other forces exist. Since the models they have for explaining everything are incomplete, there's a fairly good chance that there's something else out there, pulling matter apart or pushing it together in a different way than all the forces identified so far. A team of physicists at the University of Massachusetts, Amherst is looking for one potential fifth force--one that might arise from the...