At the end of the 18th century, the British scientist Henry Cavendish measured the force of gravity between two objects for the first time in a laboratory. The objects in question were lead balls, one ...

A fundamental constant that sets the size of the gravitational force between all objects has finally been pinned down using the quirky quantum behavior of tiny atoms. The new results could help set ...

There are quite a few fundamental constants. These are things like the speed of light (c) the charge on an electron (e), and the Planck constant (h). These constants are determined with some type of ...

It's fun to think about how we know stuff. For instance, the sun has a mass of about 2 x 10 30 kilograms. That is such an enormous mass that it's difficult to comprehend. And if it's so difficult for ...

Rich Schuler, an adjunct instructor and outreach coordinator in the physics and astronomy department at the University of Missouri-St. Louis, provides the following explanation. Gravity can be thought ...

Physicists have measured the smallest gravitational field ever recorded, in an experiment that could help in the search for a unified theory of physics. Of the four fundamental forces known to physics ...