Have you ever wondered why a feather and a hammer fall at the same rate, despite their vast difference in weight? It’s one of the most puzzling phenomena of nature, and understanding it requires ...

All of the objects in our solar system are acted upon by forces. Forces are pushes or pulls. Every force has both a strength and a direction. Applying a force on something–like pushing a toy car–can ...

As far as physicists have been able to determine, nature speaks two mutually unintelligible languages: one for gravity and one for everything else. Curves in the fabric of space-time tell planets and ...